SPACE NEWS


SPACE NEWS
--within the Solar System
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. . (to May 1, 05. Current News)
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Dec 22, 04: Due to Titan's low gravity, its atmosphere is ten times deeper than Earth's --the outer limits are at 600 km above Titan's surface!
. . On Titan, you have 1% of the sunlight that reaches Earth. And it mostly reaches the upper part of the atmosphere. The surface is even darker and colder, and chemical reactions aren't going to work as fast as they did on early Earth. Maybe these reactions are occurring, but not enough complex molecules have been produced for us to be able to detect them.
Dec 22, 04: The European Space Agency's Mars Express orbiter photographed lava flows that must have occurred within the past two million years and imply, scientists say, that volcanoes on Mars might still pump molten rock to the surface now and then.
. . And on the flanks of Olympus Mons, the largest volcano on Mars, pictures reveal material left by glaciers that were active within the past four million years or so. The gargantuan volcano --taller than any in the entire solar system-- may still harbor dust-covered snow and ice at its higher altitudes, researchers conclude.
. . One high-altitude ridge on Olympus Mons juts more than 400 meters above the surrounding terrain. Neukum and his colleagues think it is an ice cap covered by dust.
Dec 22, 04: Astronomers spotted an "asteroid" after it had flown past Earth on a course that took it so close to the planet it was below the orbits of some satellites. The space rock was relatively small, however, and would not have posed any danger had it plunged into the atmosphere. It soared over Antarctica. The object, named 2004 YD5, was about 5 meters wide. The "asteroid" passed just under the orbits of geostationary satellites, which at 36,000 km altitude.
. . On March 18, a giant boulder about 30 meters wide passed just above the orbits of geostationary satellites. Its path was bent about 15 degrees by Earth's gravity.
. . On Sept. 29, the largest asteroid ever known to pass near Earth, named Toutatis, roamed by at about four times the distance to the Moon. Astronomers had known for years the flyby would occur, since Toutatis is 4.6 km long and had been in Earth's vicinity before.
. . One study of data collected by U.S. military satellites logged 300 in-air asteroid explosions.
Dec 21, 04: Four North Carolina State University researchers have been asked by NASA to determine how greens ultimately can be grown on the red planet. The space agency selected biologists to design experiments for the Space Station that test how plants adapt to life in space or on another planet. If Americans voyage to Mars, live plants would greatly aid the mission, but people don't yet know how to grow crops or anything else there.
. . In the experiments, expected to occur in about two years, Brown and his team will use Arabidopsis, a mustard weed frequently tinkered with in molecular biology labs. The scientists will ship normal weeds, as well as weeds made less sensitive to gravity, to the space station. Using genomics tools, they will try to capture the molecular means the plants use to try to adapt.
Dec 15, 04: While a pair of NASA rovers explore Mars and the Cassini-Huygens mission peers close at Saturn, two research teams are targeting a more distant planetary quarry, the ice giant Neptune.
. . In the separate studies, planetary scientists and engineers are drawing up plans to send an orbiter laden with atmospheric probes and landers to Neptune, the eighth planet from the Sun. While each mission has its own way of reaching Neptune, both seek a better understanding of the planet and its surrounding 13 known moons, especially the oddball Triton.
. . A version of the Neptune mission, which features the use of a nuclear fission reactor and ion propulsion to reach the ice giant and a timescale that spans two decades, is also under scrutiny.
. . While the same case for exploration can be made for Uranus, a fellow ice giant, the kicker is Neptune's largest moon Triton, which astronomers believe is a non-native captive of its parent planet. It circles Neptune in a retrograde orbit, in the opposite direction of Neptune's rotation. It has a gossamer thin atmosphere where parachutes would be useless for any landing probe.
. . Both studies are also looking at sending a pair of Triton landers, though setting the spacecraft down on the icy moon may be tricky. The surface is an extreme 35 degrees Kelvin (-238 degrees Celsius), and since Triton sports geysers and possibly seismic activity, landers would have to operate for long periods of time to monitor it.
Dec 15, 04: NASA planners are now orchestrating America's return to the Moon, with many experts hoping to hang their space helmet on the likelihood that ice is stored within permanently shadowed craters at the lunar poles. Such an ice resource is considered invaluable if processed to create life-sustaining oxygen and water, even transformed into rocket fuel for propelling spacecraft beyond the Moon. However, whether or not this material --spotted by lunar orbiters of years past-- is actually water ice or hydrogen, is open to question.
. . As a first robotic step back to the Moon, NASA is moving out on the Lunar Reconnaissance Orbiter (LRO) and will soon announce the scientific payload this craft will carry. The planning date for LRO launch is October 15, 2008.
. . Now looping the Moon is the European Space Agency's SMART-1 probe. "SMART-1 is equipped with sensors to peek in the permanent night at the bottom of polar craters. Even though there is no direct sunlight, the light reflected from the rims of craters could amount to 50 Earthshine, so this could be measurable."
. . NASA is reviewing a New Frontiers project dubbed Moonrise --a lunar South Pole-Aitken Basin sample return mission. Moonrise would involve two identical landers on the surface near the Moon's south pole and the return of over two kg of lunar materials.
. . If Moonrise gets the go-ahead, this mission must be ready for launch no later than June 30, 2010, within a mission cost cap of $700 million. "We just have to know what equipment to take. That's because you harvest solar wind hydrogen one way and you harvest the water ice another way. It's still good news. In both cases, it's the hydrogen that is the valuable thing", Binder concluded, "because there's plenty of oxygen around. We know that you can crack the rocks and get the metal and oxygen out."
Dec 8, 04: Future long-duration space crews may need up to 40 different food processing machines to turn crops such as wheat and tomatoes into edible foods like bread and cereals, NASA officials estimated. "As we go on to longer-duration missions, it makes sense to become a little more self-sufficient with our food."
. . They need to determine how small amounts of gases emitted by plants can affect their spacecraft surroundings. "It's more than just turning carbon dioxide into oxygen", Larrat said. "There are minute quantities of other gases that on Earth you'd never think about."
Spectral measurements and light intensity data provide evidence for hydrated minerals on Phoebe's surface, as well as carbon dioxide and solid hydrocarbons similar to those found in comets. The 220km-wide moon is mixture of ice, rock and carbon compounds similar to material in Pluto and in Neptune's moon Triton.
Dec 13, 04: The Mars rover Spirit found a mineral linked to water during its exploration of the Red Planet, NASA's Jet Propulsion Laboratory said today. Scientists identified the mineral goethite.
. . "Goethite, like the jarosite that Opportunity found on the other side of Mars, is strong evidence for water activity." Goethite forms only in the presence of water, although it may be in liquid, ice or gaseous form. The Columbia Hills bedrock was previously found to have hematite, a mineral that usually, but not always, forms in the presence of water. "The combination suggests that this was not a deep-water environment but more of a salt flat, alternately wet and dry."
. . Frost has also been seen on the rover during some mornings.
Dec 8, 04: A large planet-like object out in the realm of Pluto shows signs of either a relatively recent collision or perhaps volcanic activity, astronomers said today.
. . Quaoar (pronounced kwa-whar or kwah-o-wahr) resides in the Kuiper Belt (Koy'-per), a region of icy objects beyond Neptune's orbit. Astronomers expect most Kuiper Belt Objects (KBOs) to be relatively pristine leftovers from the formation of the solar system. They are the comets that have not yet made a close pass around, the wannabe planets that never grew quite big enough. Quaoar is roughly 1,260 km wide, second only in size among KBOs to Pluto --the biggest, with a diameter of 2,400 km.
. . KBOs are thought to be composed of rock, water ice and various other frozen chemicals. Hundreds have been found, but most are too far away and too small to study in detail. Water ice has been detected on a few.
. . Jewitt and a colleague found signs of ammonia hydrate and crystalline water ice on the surface of Quaoar. Both substances should be destroyed over a few million years by particle irradiation, they say. That's a short period of time, considering the solar system's entire life of 4.6 billion years.
. . "We conclude that Quaoar has been recently resurfaced, either by impact exposure of previously buried ices or by cryovolcanic outgassing, or by a combination of these processes."
. . Scientists think water must be heated to about minus 279.7 Fahrenheit (100 Kelvin) in order to form crystalline ice. Water ice incorporated into an object at low temperatures ought to be amorphous.
. . The Kuiper Belt is so far from the Sun that the temperature there is less than 50 C (90 F) above absolute zero (-273 C, -459 F).
Dec 8, 04: Future long-duration space crews may need up to 40 different food processing machines to turn crops such as wheat and tomatoes into edible foods like bread and cereals, NASA officials estimated. "As we go on to longer-duration missions, it makes sense to become a little more self-sufficient with our food."
. . They need to determine how small amounts of gases emitted by plants can affect their spacecraft surroundings. "It's more than just turning carbon dioxide into oxygen", Larrat said. "There are minute quantities of other gases that on Earth you'd never think about."
Dec 8, 04: Comet Machholz will be at its closest to Earth Jan. 5-6, '05, when it will be 32 million km away. People with dark rural skies and a good map should be able to find it on Moon-free nights now into January. They suggest looking for it when the Moon is out of the picture, such as around Dec. 11 when it will be at its New phase.
Dec 5, 04: Titan is unique in the Solar System. It is the only planetary satellite with a substantial atmosphere. It is rich in nitrogen, methane, other organic (or carbon-based) molecules and nitriles (in which carbon atoms are triple-bonded to nitrogen atoms) such as hydrogen cyanide.
. . "We've done some calculations for what wind-driven waves might look like on Titan and they are actually quite scary. Under the same conditions, waves on Titan could be 10 times larger than on Earth." So, although Huygens is sealed and should float, if it lands on liquid, there is the prospect it could be overwhelmed by a massive surge of liquid hydrocarbons.
. . "We've also calculated the waves will be very slow; so I guess my dream scenario is that the camera picks up this massive wave on the horizon trundling towards us and we take measurements all the time before the screens suddenly go blank", Professor Zanecki joked.
. . Cassini-Huygens is a cooperative project between the US space agency, Esa and the Italian Space Agency.
Dec 2, 04: A new study finds no evidence for an impact 250 million years ago, at what is known as the end of the Permian Era. A team of scientists led by Christian Koeberl from the University of Vienna studied rock samples in sections of the planet's crust in Austria and Italy that are dated to the end-Permian extinction. "Our geochemical analyses reveal no tangible evidence of extraterrestrial impact", Koeberl said. "This suggests the mass extinction must have been home-grown."
. . "Asteroids" bring elements to Earth that are rare here. Excess iridium, helium-3 and osmium-187, for example, can serve as calling cards for a space rock.
. . In a series of previous studies, a group led by Luann Becker of the University of California, Santa Barbara has claimed evidence from other locations for such extraterrestrial signatures, all associated with the end-Permian event. Several scientists have doubted those results, however.
. . The new study found only very small levels of iridium in the 250-million-year-old rocks, and revealed no traces of helium-3 or osmium-187. The slight concentrations of potentially extraterrestrial materials were probably instead deposited by chemical interactions involving low oxygen levels in the ocean and high levels of carbon dioxide in the atmosphere, Koeberl said. The likely cause of the excess carbon dioxide: volcanic activity. [what about a comet?]
Dec 1, 04: As Lunar exploration looms larger among the growing community of scientists and engineers from Europe, India, China, Japan, and the United States, a robotic lunar village is gaining support, leading to a permanent human presence on the Moon by 2024.
. . The Udaipur Declaration specifically recommends several steps: Coordination of international efforts for the establishment of "standards" to facilitate lunar exploitation and settlement -- e.g., use of the metric system; well-characterized lunar soil simulants (materials that mimic properties of true lunar regolith); common data formats and instrument interfaces, as well as frequency and power needs, and urges establishment of a standard lunar geodetic network.
. . Lastly, the statement recommends that the 1979 "Moon Treaty" be "revisited, refined, and revised as necessary in light of the present-day impetus for expeditions, both robotic and human, to the Moon by several nations."
. . The gathering, held November 22-26, involved some 200 scientists from 17 countries, with experts focusing on new and planned missions to the Moon as well as plotting out concepts for long term exploration of Luna and utilization of lunar resources.
Dec 1, 04: In 2010: The Year We Make Contact, was the space age equivalent of playing air bag bumper car with Jupiter. A "ballute" --a fusion word from balloon and parachute-- was used to slow the spacecraft once it reached the giant planet, a device that allows for aerocapture around a celestial body that's enveloped in an atmosphere.
. . NASA selected a concept from Ball Aerospace & Technologies Corporation for inflatable thin-film ballutes for return from the Moon. Not only Moon-to-Earth traffic could benefit by using the ballute/aerocapture technique. So too could missions to Mars, as well as future probes to Titan, the largest moon of Saturn, and other distant destinations. Taking this approach translates to using less propellant.
Dec 1, 04: The outer reaches of our solar system may have been shaped long ago by a close encounter with another star that tore up both nascent planetary systems like colliding buzz saws, astronomers said today.
. . The dramatic encounter, if it occurred, might even have deposited an alien world into our midst. The scenario was devised to describe unexplained observations of the solar system but is based on speculation about actual events. The resulting computer simulations suggest a range possible outcomes for a close celestial brush shortly after the planets formed, about 4.5 billion years ago.
. . "It’s possible that some of the objects in our solar system actually formed around another star." There is no firm evidence that the Sun ever interacted closely with another star, but many astronomers think the Sun was probably born amid a tight huddle of stars, all of which formed out of the same gas cloud. Most stars in the galaxy are known to form in such clusters. The Sun was later ejected from the cluster, the thinking goes. During that chaotic early time as planets, comets and "asteroid"s were taking shape, its conceivable the Sun passed precariously close to another star.
. . The new computer model shows how young planet-sized objects with circular orbits around the Sun might have been gravitationally slung onto elongated paths, putting them too far away to spot with current technology. Such an interaction might also have caused a sharp cutoff detected at the outer edge of the Kuiper Belt, a region of icy objects beyond Neptune.
. . One impetus for the modeling was to explain the presence of Sedna, a world well beyond Pluto that was discovered last year. Sedna is at least half as big as Pluto. It has a highly elongated orbit that is entirely outside the Kuiper Belt. Astronomers don't know how it got on such a course, but they now suspect there may be many similar objects out there awaiting discovery.
. . They figure a near-collision occurred when our Sun was at least 30 million years old, and probably no more than 200 million years old. A proximity of between 22.5-30.5 billion km could have disrupted the outer Kuiper Belt without altering the paths of the inner planets, they found.
. . It is also possible that Sedna was nudged onto its present course by an Earth-sized planet that is no longer in the Kuiper Belt, or by a handful of other means. "The difficulty, of course, is that with but one single object, we can come up with a large number of plausible ways to get it there, but we have no way of proving any one of them", Brown said. "The solution is to go out and find more of these distant objects."
Nov 29, 04: A new study of Eros provides further insight into its structure by modeling how impacts by other asteroids likely rung its bell. The model supports previous work that maintains Eros, a potato-shaped rock 33 km long, is not solid, but rather a fractured set of blocks, each as big as a small town. The blocks, each miles wide, fit like a 3-D jigsaw puzzle and are held together by their collective, albeit weak gravity.
. . In the new work, Richardson assumed this structure and plugged it into a computer model of seismic activity. The results seem to explain how previous craters on the asteroid get obscured and washed out by the shaking that follows an impact.
. . * The European Space Agency's Rosetta spacecraft is on it way to comet 67/P Churyumov-Gerasimenko, where it will set anchor with harpoons, then use radio waves to explore the interior.
. . * The Japanese Hayabusa spacecraft is expected to reach asteroid 25143 Itokawa the middle of next year; it will touch the asteroid's surface and fire a small bullet, knocking grains into a canister for return to Earth.
. . * NASA's Deep Impact mission will fire a 350-kg projectile into comet Tempel 1, photograph the impact and analyze the fresh crater.
. . * NASA's Dawn mission, set for launch in 2006, will orbit asteroid Ceres, the largest known asteroid with a diameter of 930 km.
. . Asphaug holds Ceres up as an example of how little is agreed upon among planetary scientists and asteroid experts. Ceres, he says, is arguably a planet if Pluto is argued to be one. [it isn't!]
Nov 21, 04: The Kuiper (Coy'-per) Belt extends out to some 8 billion km from the Sun. "Given that our survey has covered almost the entire region of the Kuiper Belt, I'm willing to bet these days that nothing larger than Pluto will be found in the Kuiper Belt", says Caltech astronomer Mike Brown.
. . As hope fades, a study released earlier this month shows that some KBOs are smaller than had been assumed. One object, catalogued as 2002 AW197, was thought to be two-thirds the diameter of Pluto. Stansberry has now shrunk that estimate to about one-third.
. . Some of the larger objects out there have not shrunk, however, because their actual albedos were already fairly well known. Last November, Mike Brown's team found a world at least half as large as Pluto. They named it Sedna. Sedna's elongated orbit is outside the Kuiper Belt, ranging from 76 to 1,000 AU. Sedna was found only because it is currently near the innermost stretch of its travels. Nobody expected to find an object like Sedna in the largely empty space between the Kuiper Belt and the Oort Cloud.
. . "I'd also be willing to bet that there are many objects larger than Pluto out in the region of space where Sedna lives", Brown said last week. Out to about 1,000 AU, he speculates that there could be 10 or 20 Pluto-sized objects, "and a handful of larger things, too." Some of these suspected worlds could be as big as Mercury or even Mars, he said.
Nov 17, 04: There are over eight thousand satellites and other large objects in orbit around the Earth. Satellites or other objects in orbit higher than 700 kilometers will stay there for hundreds of years; LEO satellites have an average working life of just five years.
. . The Terminator Tether is bolted onto the satellite during construction. Once launched and operational, the device is dormant, waking up periodically to check the status of the satellite and to listen for activation commands. When the command to deorbit the spacecraft is given, the 5 kilometer cable is deployed. The cable interacts with ionospheric plasma and the Earth's magnetic field; this produces a current along the tether which causes a net drag on the spacecraft, lowering its orbit until it burns up in the Earth's atmosphere.
Nov 15, 04: Work is underway to establish the first interplanetary laser communication link. The $300 million NASA experiment, if successful, will connect robotic spacecraft at Mars with scientists back on Earth via a beam of light traveling some 300 million kilometers. For scientists eager to download bandwidth-intensive imagery and other data collected by planetary orbiters, probes and landers, the laser communications would offer a dramatic breakthrough in the amounts of information spacecraft can reliably transmit back to Earth.
. . The 5-watt [!] laser NASA plans to test at Mars by the end of the decade is expected to transmit data at rates nearly 10 times faster than any existing interplanetary radio communications link. The difference, NASA officials said, will be comparable to moving from a dial-up modem to a broadband Internet connection.
. . But the new tech is not without its challenges and NASA says it could be decades before lasers are ready to take over as the primary means of communicating with spacecraft. A big part of the challenge is being able to point accurately toward the Earth." In fact... the southwestern corner of the US.
Nov 12, 04: Titan may have molten ice welling up to the surface from its warm interior. Mission scientists are speculating that this could be fluid oozing across the surface: a so-called cryovolcanic flow. It's an analogue to volcanism on Earth that is not molten rock but, at Titan's very cold temperatures, molten ice." [Huh? Isn't that called... water?!] Cryovolcanic flows are also hypothesized to exist on Jupiter's moon Ganymede.
. . The fact that the lower (southern) edges of the features in the synthetic aperture radar image are brighter is consistent with the structure being raised above the relatively featureless darker background.
. . Scientists have been puzzled by the relative lack of impact craters on the surface of Titan. A likely explanation for this seems to be that the surface of this moon is constantly being resurfaced by some sort of geological activity. The image covers an area about 150km (90 miles) square in Titan's northern hemisphere.
Nov 12, 04: An electrodynamic tether (EDT) is a simple idea, but one with an amazing number of uses. An EDT system is made up of two masses in orbit connected by a long, flexible, electrically conductive cable; the tether is essentially a wire that moves through the magnetic field of the Earth (or another planet or large body). An EDT takes advantage of two basic principles of electromagnetism: current is produced when a conductive wire moves through a magnetic field, and the field exerts a force on the current.
. . By adding a battery (or solar panel) to the EDT circuit, the induced current is overcome, reversing the current direction; the force experienced by the tether is now in the same direction as the EDT's motion. In other words, this produces thrust, raising its orbital attitude.
. . The International Space Station will require over seventy tons of propellant over the next ten years to keep its orbit from decaying. All of this reaction mass must be hauled up the gravity well at a cost of $7000 per pound! A properly deployed EDT, combined with another power source, could actually push itself forward on the Earth's magnetic field, speeding the IST up without the use of any propellant.
. . The biggest problems are electromechanical; EDTs experience high voltages in space. Also, EDTs are prone to vibrations that produce significant mechanical forces. Also, development has been slow; a program planned for launch in 2004, ProSEDs, was repeatedly postponed and ultimately canceled.
Nov 12, 04: Phobos is slowly falling down to Mars and is expected to crash into the planet in the next few million years. Measuring about 27km by 19km, Phobos (from the Greek for fear) is the larger of two moons. Phobos appears to be composed of C-type rock, similar to blackish carbonaceous chondrite asteroids. But some scientists say there is evidence that Phobos and Deimos are by-products of the break-up of a huge moon that once circled Mars.
Nov 12, 04: The probe Smart 1 will test a highly efficient solar-electric propulsion system as one of its key mission objectives. Smart 1 will survey a flat region known as the Peak of Eternal Light near the south pole which is thought to be bathed in perpetual sunlight and also appears to be flat. This could render it a particularly suitable spot for future manned lunar bases. The temperature in this region is stable at -20C; much more acceptable than the equator where the temperature varies from 120C to -170C. It will also look for water ice in very deep craters nearby. It will also search for possible building materials for a future moonbase.
. . "Smart-1 can be used as a precursor for long-term exploration of the planets."
Nov 12, 04: The team behind the Beagle 2 mission to Mars has unveiled its design for the successor to the British spacecraft. Scientists hope to launch two landing craft from an orbiter that could fly in 2009.
. . Advances in solar cell technology mean the craft could cope with half the number of solar panels its predecessor carried. New lithium-ion technology allows for a battery that can work at lower temperatures, so that the new lander requires less heater power. The probe might also make use of "deadbeat" airbags to cushion its landing. These airbags inflate like pillows under the lander before it touches down and would replace the so-called bouncing ball airbags. "You only land once. You're not going to bounce all the way down a hill and finish up in the biggest hole."
. . It would weigh 131kg. A gas analysis package (Gap) inside the lander shell will test soil and rock for signs of microbial life. Scientists have also been looking at so-called "life chips" that can detect amino acids.
Nov 10, 04: A solar sail spacecraft designed to be propelled by the pressure of sunlight will be launched early next year, The Planetary Society said. The mission, costing just under $4 million, will attempt the first controlled flight of a solar sail. Solar sails are envisioned as a means for achieving interstellar flight. Though very gentle, solar pressure should allow such spacecraft to gradually build up great speeds over time, and cover great distances.
. . Inflatable tubes will stretch the sail material out and hold it rigid in eight 49.5-foot-long structures resembling the blades of a windmill. Each blade can be turned to reflect sunlight in different directions so that the craft can "tack" much like a sailboat in the wind.
. . Cosmos 1 is a project of The Planetary Society, which was founded in 1980 by the late astronomer Carl Sagan.
Nov 1, 04: Challenging conventional theory, new scientific research suggests the dinosaurs may have been scorched into extinction by an asteroid collision 65 million years ago that unleashed 10 billion times more power than the Hiroshima nuclear bomb.
. . Earth's temperatures soared, the sky turned red and trees all over the planet burst into flames, said atmospheric physicist Brian Toon. Among the few survivors would have been animals living in water or burrowed in the ground like turtles, small mammals and crocodiles. Creatures living near ground zero would have been vaporized immediately while those in the Caribbean area and southern United States would have drowned in 100-meter-high (330-feet) tsunamis when the asteroid impacted near today's Gulf of Mexico shoreline at a speed of 54,000 kph (33,750 mph).
. . Then, a column of red-hot steam and dust soared thousands of miles into space and most of it fell back toward Earth within a few hours, turning the heavens into hell. "The entire sky would be radiating at you. It would be like standing next to a giant fire; you'd be burned very severely." Land dinosaurs all around the world perished from the intense heat of several hundred degrees F, said Toon.
. . He agrees with other scientists that the dust cloud later cooled and blocked out the sun, but says the land dinosaurs were already history by that time. The darkness finished off many of the remaining marine reptiles and fish by killing plankton and disrupting the food chain, said Toon.
Oct 29, 04: The Saturn-probe team was surprised by the apparent absence of volcanic craters or vents they predicted would replenish the methane. The data also seem to show that Titan could be covered in up to 656 feet of fluffy hydrocarbon "snow" that fell out of the heavy atmosphere. It is still not clear how much of the surface is liquid and how much is solid and whether the "land masses" are ice. Cassini is set to collect more images of Titan in its Dec. 13 fly-by.
Oct 28, 04: Saturn's mysterious moon Titan appears to have an environment rich in the carbon-based molecules that spawned life on Earth and winds that etched streaks into its icy surface, NASA scientists said. Most exciting to scientists were apparent signs of large amounts of a sort of primordial slush on its frozen surface. Images also suggested "an enormous amount of geology going on" on Titan including past eruptions of water-vapor-spewing volcanoes and "eggshell cracking" on its surface.
. . The radar images showed streaks that resembled lava flows on Venus, triangular upthrusts that could be rocks, and what could be a chain of frozen lakes containing organic matter. The pix cover just 1% of Titan's surface, also showed a deep surface layer of something that appears to be organic material rather than a rocky face. A possible region of lakes was depicted as very dark, which in radar data is a characteristic of a signal bouncing off a very smooth surface like a liquid.
. . Tho Titan's equatorial temperature stays far below freezing, the water ice at its core may be mixed with ammonia, whose lower freezing point may allow it to thaw and flow across the moon's surface in volcanic eruptions, scientists said. The resulting streaks and flows observed around Titan's midsection also could have been caused by the movement of its heavy atmosphere.
. . It's expected to fly by Titan 44 more times during its four-year mission.
Oct 25, 04: Spacecraft Cassini carries a European Space Agency probe. It's set to pass within 1200 kms of Titan's surface. It will snap infrared and radar images 100 times sharper than any taken so far. Its photos can pick out features the size of a football field. Tuesday evening, it will download data and images collected during its pass near Titan --one of 45 planned for the spacecraft's four-year tour of Saturn and its moons.
. . In January, Cassini is expected to drop off the Huygens probe. If it survives a parachute-assisted descent through Titan's atmosphere, Huygens is expected to transmit data for several minutes before freezing in temperatures of -179C, or sinking beneath a lake of methane.
. . Expected: "No primordial soup but maybe primordial ice cream..."
Oct 21, 04: The Deep Impact mission, which will cost some $311 million, will let future investigators know whether it would be easy to attach thrusters to a comet to push it out of the way. "The properties of the cometary nucleus (of Tempel 1)... are probably representative of the really dark near-Earth objects, which are likely dormant comets", A'Hearn said.
. . The impact with Tempel 1 is likely to produce a crater the size of a football stadium on a comet with a diameter of about 5Km.
. . But if the comet's nucleus is more like a solid ice cube, the impact might create a much smaller crater.
. . If the comet is made of what A'Hearn called solid pumice rock --hard but full of holes-- the impact would simply compress the existing material.
. . Or the comet might even have the consistency of powdery snow, in which case the impactor would tunnel right through it.
Oct 21, 04: If a six-person crew takes enough ready-made food, oxygen and water with it to survive a 1,000-day mission, the weight is 30 tons, says the European Space Agency (ESA). Factor in additional water for washing (say 20 kilos per person per day), and the total rises by another 120 tons. "The longer a mission is, the more interest there is in recycling your waste and growing your own food."
. . They've identified eight plants that have good potential for providing the necessary vitamins, protein and carbohydrates for astronauts, who are vulnerable to loss in muscle tone and bone density. The eight are tomatoes, lettuce, potatoes, soybeans, spinach, onions and wheat, as well as rice, which needs lots of cultivation space and has a lot of non-edible waste. With that exception, these plants are so versatile that scientists have achieved a recycling rate of up to 60%, and the Ducasse cooks, using raw ingredients or derivatives, have already conceived between 70 and 80 recipes.
. . Spirulina is a grey-green algae that floats on water. It has a very high (60%) protein content and is harvested in parts of Africa. "It has the look and texture of mud and has a metallic taste."
. . Breeding live animals on Mars will be out of the question. Another possibility is to grow meat from the muscle cell lines of various animals like fish. A NASA-funded team has already carried out experiments, taking live muscle tissues from freshly-killed goldfish and raising them in cell-culture fluid for a week, a process that caused the tissue to grow by 14%.
Oct 15, 04: A comet or asteroid smashed into modern-day Germany some 2,200 years ago, unleashing energy equivalent to thousands of atomic bombs, scientists revealed. The 1.1-kilometer diameter rock wacked into southeastern Bavaria, leaving an "exceptional field" of meteorites and impact craters that stretch from the town of Altoetting to an area around Lake Chiemsee, the scientists said.
. . Colliding with the Earth's atmosphere at more than 43,000 kms per hour, the space rock probably broke up at an altitude of 70 kms. The biggest chunk smashed into the ground with a force equivalent to 106 million tons of TNT, or 8,500 Hiroshima bombs. "The forest beneath the blast would have ignited suddenly, burning until the impact's blast wave shut down the conflagration. Dust may have been blown into the stratosphere, where it would have been transported around the globe easily... The region must have been devastated for decades."
. . The biggest crater is now a circular lake called Tuettensee, measuring 370 meters across. Scores of smaller craters and other meteorite impacts can be spotted in an elliptical field, inflicted by other debris. Aerial infrared photography established that the distinctive holes in the local countryside had the characteristic round form and "clear uplifted rim" of an impact crater. Minerals ejected around the crater were found by geological analysis to be gupeiite and xifengite, iron-silicon alloys that were also found in meteorites recovered in China and Antarctica.
. . Additional evidence comes from local discoveries of Celtic artifacts, which appear to have been scorched on one side. That helped to establish an approximate date for the impact of between 480 and 30 BC. The figure may be fine-tuned to around 200 BC, thanks to tree-ring evidence from preserved Irish oaks, which show a slowing in growth around 207 BC.
. . The object is more likely to have been a comet than an asteroid, given the length of the ellipse and scattered debris, the report says. In 1908, a comet or asteroid exploided over Tunguska, Siberia, flattening the forest for hundreds of square kilometers around.
Oct 13, 04: The next spacecraft destined for Mars is rapidly coming together here on Earth --an interplanetary probe that carries the most powerful instruments ever sent there. NASA's Mars Reconnaissance Orbiter --MRO-- is being readied for sendoff next year. The huge spacecraft carries a suite of instruments, including a camera system able to provide ultra-close-up images of Mars' surface, and a sounder to probe for water that might linger subsurface on the planet. MRO can image objects on Mars as small as a dinner plate. Its mission requirement is to operate for 5.4 years. But it has the built-in chutzpa to keep on keeping on for a decade.
. . MRO is a crucial link to a wave of upcoming robotic landers slated to dot Mars in coming years. But more so, MRO stamps the passport for human visitation rights, road mapping Mars to help resolve where expeditionary crews can best land, and sustain their presence.
. . It has an unyielding launch window of August 2005.
Oct 11, 04: Both Deep Impact spacecraft have completed the final environmental testing phase, a key step before liftoff of the mission --Dec 04. The two Deep Impact spacecraft have undergone extensive thermal vacuum, electromagnetic conductance, electromagnetic interference, vibration and acoustic testing.
. . Objective of the mission is to study the pristine interior of a comet by excavating a huge crater in Comet Tempel 1. Once set free from the Flyby spacecraft, the Impactor may form a football stadium-sized crater in the comet that could be as deep as 14-stories.
. . This cosmic rear-ender comes on America's Independence Day: July 4, 2005.
. . Deep Impact's telescopes, cameras and spectrometer aboard the Flyby spacecraft will witness the impact and return data on the pristine material in the crater and the material ejected by the impact. The High Resolution Imager aboard the Flyby spacecraft will be one of the largest interplanetary telescopes ever flown in order to record the details of the collision.
. . Meanwhile, the Impactor spacecraft will also provide close-encounter photos just prior to impact, giving scientists the most complete view of a comet yet.
Oct 7, 04: Almost by accident, NASA's Mars rover Opportunity has found a rock that may point to a second water event in the red planet's past. Its cameras came across "Escher", an oddly cracked rock that researchers said may have fractured after being soaked during some sort of water event. Follow-up observations at a rock called "Wopmay" may shed more light. If verified, it would point to a secondary water episode that occurred after Endurance Crater formed. Since only the surfaces of the rocks were altered, scientists theorized the water did not stay for long and may have come from melting frost or underground ice.
. . "Escher" cracked and fractured into polygonal shapes. On Earth, such polygonal rock patterns have been known to be associated with water, but they could just as well have formed when an impact smacked into the surface elsewhere on Meridiani Planum.
. . Opportunity drilled into "Escher's" surface with its arm-mounted rock abrasion tool (RAT), finding the chemistry of its innards substantially different from its surface. While that hints at a possible past interaction with water, "Escher" is the only the first Martian rock in which the polygonal patterns have been found and its flat orientation on the floor of Endurance Crater poses a limited view into the rock's history.
. . Spirit drove about 3km from its landing site to the Columbia Hills, where it found rocks, older than the lava flows forming the floor of Gusev crater, that contained water-related minerals. "Every single rock in the hills has shown alteration by liquid water."
. . Wopmay, which researchers said shows some similarities with Escher, stands upright on the Martian surface and could answer questions its predecessor leaves outstanding.
Oct 8, 04: Having succeeded in awarding the sub-orbital prize, the X Prize Foundation and the World Technology Network announced today the formation of a joint venture to launch a series of technology incentive prizes to help spur innovation and breakthroughs in a range of scientific arenas.
. . According to the X Prize Foundation and the World Technology Network, examples of privately-funded solutions in scientific and social fields might include:
. . 1. Transportation: Demonstration of a 4-seat vehicle able to achieve 200 miles per gallon in a cross country race.
. . 2. Nanotechnology: Construction of a pre-determined molecule by an assembler.
. . 3. Aging deceleration: Extension of mammal life, or demonstrated evidence of aging reversal.
. . 4. Education: Demonstration of a self-sufficient education facility able to operate independently and educate villagers anywhere on the planet.

"We're in a public suggestion phase. And that phase ought to be the phase when no idea is too far out and no idea is too ambitious."

Oct 6, 04: And there's a new space-prize! This one demands faster and hardier vehicles, capable of orbital flights. NASA's shuttles reach about 27,000 kph to attain orbit and withstand reentry temps up to 1648 degrees C (3,000 degrees F). Suborbital flights can be significantly slower --SpaceShipOne: Mach 3 or 4,184 kph (2,600 mph).
. . America's Space Prize, a $50 million contest under development by Nevada millionaire Robert Bigelow, looks to push privately funded human spaceflight into orbit, and ultimately on missions to a planned space station. Winners would snag the $50 million prize and first rights to service the Nautilus inflatable orbital modules under development by Bigelow Aerospace.
. . More advanced designs are needed to withstand the reentry stresses and develop the tricky ability to dock with an orbiting facility. Space Prize vehicles will be required to carry the weight of at least five people, two more than the suborbital X Prize.
. . Imagine the difference this way: a sub-orbital reaches its peak altitude & falls back --the apex-speed being essentially zero (plus earth's rotational speed). To achieve orbit, a ship then needs an additional say, 25,000 kph! It's not the altitude, it's making the orbital speed required to stay there!
. . The International Space Station (ISS) orbits the Earth at an altitude of about 403 km (250 miles).
. . According to Bigelow, the next three years will see launches of scaled versions of the Nautilus module --the first private space station-- including one-third scale versions in 2005 and 2006, and a 45% version in 2007. A full-size Nautilus test flight could be ready by 2008, with a final version ready for the Space Prize in January 2010. One Nautilus module contains about 330 cubic meters. The habitable volume of the current ISS configuration is about 425 cubic meters.
Sept 30, 04: An international team of scientists has found life on a Norwegian island. No surprises there, but the successful field test of a collection of life-detection instruments may be a stepping stone for future endeavors to sniff out life on Mars. "It's the first time we have employed a package of tools ranging from spectroscopy to microbial techniques."
. . The AMASE researchers found many microbes living in the rocks of Svalbard --"cryptoendolithic" organisms. [love that word!]
Sept 27, 04: Like a comet, Mars has a tail, a stream of particles pushed away from the planet by the Sun's energy. New measurements of the Martian tail reveal how much air the planet loses to space every day and allow scientists to estimate the tremendous loss that may have occurred billions of years ago. About 1 kilogram of mass is lost to space every second.
. . Mars probably had a magnetic field 3.5 billion years ago, Lundin said, but it didn't stick. Thereafter, while the atmosphere was still presumably dense —-perhaps 10 times thicker than today-— the loss rate for water and other substances would have been perhaps 100 times higher than it is now.
Almost all the 138 moons of our solar system seem to have captured rotation --their "days" equal their "years." The list doesn't include many of the moons because we lack rotational data.
Sept 28, 04: A spacecraft orbiting Mars photographed Spirit --one of NASA's rovers and its tracks on the surface. In normal operations, the spacecraft can pick out objects on the surface that are about 13 feet to 16 feet across. The roll technique allows objects as small as 4.9 feet to be seen. The twin rovers, Spirit and Opportunity, are 4.9 feet high, 7.5 feet wide and 5.2 feet long.
Sept 27, 04: The largest asteroid ever known to pass near Earth is making a close celestial brush with the planet this week. The space rock, named Toutatis, will not hit Earth, despite rumors of possible doom that have circulated the Internet for months. Humanity is very fortunate there won't be an impact, as the asteroid is large enough to cause global devastation. Toutatis is about 4.6 by 2.4 km. It looks something like a pockmarked dumbbell.
. . Sept 29 it will be within 1.5 million km of Earth, or about four times the distance to Luna --closer to Earth than it has been since 1353. No space rock this big will pass so close in the next century, but it will still be 16 times dimmer than the faintest stars that can be seen with unaided eyes.
. . Toutatis will speed by Earth at 22,000 miles per hour. It makes a roughly four-year trip around the sun that swings from just inside Earth's orbit to outside the orbit of Mars.
Sept 15, 04: People could land on Mars in the next 20 to 30 years, provided scientists can find water on the red planet, the head of NASA's surface exploration mission said. "There are indications that there is actually water that seeps out the side of the canyon, and going down the side it evaporates. We believe it's an ongoing process."
Sept 15, 04: NASA has transferred its X-37 technology demonstration program to the Pentagon's Defense Advanced Research Projects Agency (DARPA), which plans to go ahead with atmospheric drop tests of the prototype space plane next year. The U.S. space agency would remain involved in the X-37 program, but DARPA is now running the show.
. . It was first reported by the Desert News, a newspaper covering Mojave, Calif., and surrounding areas. The newspaper also reported that the X-37 would be carried aloft for next year's drop tests by the White Knight, the Scaled Composites-built aircraft that carried SpaceShipOne for its historic suborbital space shot.
. . But in late 2003, NASA directed Boeing to throttle back on development of the orbit and re-entry vehicle and has since directed Boeing to stop work on that part of the program altogether. X-37 was dealt a further setback earlier this year when a NASA review concluded that the program was not a good fit with the agency's new space exploration agenda.
Aug 26, 04: A rock measuring less than 10 meters across zipped past the Earth at the closest distance ever detected, but it would not have posed any threat if it had struck. It missed the Earth on March 31 by the wafer-thin gap of 6,500 km. It would have exploded harmlessly in the upper atmosphere had it hit."
. . Given the large population of asteroids of this size --a population estimated to be a couple of hundred million in the Solar System-- the statistical chance of a flyby is "more than once a year" and the risk of an actual impact is rated once every several years.
Aug 16, 04: With a new spacecraft --MESSENGER-- bound for Mercury, that tiny planet near the heart of the solar system, researchers are hoping to solve a slew of riddles, especially a theory that the planet is shrinking, contracting in on itself as its core slowly freezes. "Mercury is a small enough planet that its core should have frozen about 2.2 billion years ago."
. . The theory is based on images from NASA's Mariner 10 mission in the 1970s that show randomly strewn scarps across half of Mercury, where the surface appears to have buckled from within. Scientists hope that the new spacecraft will shed new light on both Mercury's surface as well as its metallic core. It will collect surface composition data on material that may have once spewed out of the planet's interior.
. . Scientists estimate the planet's surface has shrunk inward between less than one kilometer and three kilometers in all. Mariner 10 returned images of great scarps biting deep into the planet's surface. One such scarp, Discovery Rupes, cuts 1.6-km into the crust as it snakes across the surface.
. . Mercury is 4,878 km in diameter, a bit larger than Luna. It's extremely dense for its size --comparable to Earth's density-- researchers believe it has a large metallic, most likely iron core. But exactly how large the core is, whether its outer regions are molten, and whether it rotates to power the planet's strong magnetic field, are still unknown.
. . The MESSENGER, or MErcury Surface, Space ENvironment, GEochemistry, and Ranging, mission launched on Aug. 3 this year and is expected to reach Mercury in March of 2011. Not only will the spacecraft spend an entire year mapping the entire planet, as opposed to the Mariner 10's 45% scan, it will also do so with unprecedented detail. The cameras onboard MESSENGER can resolve surface features down to just 18 meters across, compared to the 1.6-km resolution offered by Mariner 10.
. . The spacecraft's Mercury Laser Altimeter instrument will track how the planet wobbles on its axis to help researchers determine the state of its core. Surface-scanning tools, meanwhile, will study the composition of ancient lava flows providing a window into Mercury's mantle.
Aug 11, 04: India is rethinking its plan to send a man to the moon by 2015, as the mission would cost a lot of money and yield very little in return, the national space agency said. Although he did not rule out the manned mission completely, he indicated that the ISRO no longer favors it. Instrument-based study "is less expensive, more reliable and it can be for a longer duration". than a manned mission, he said. Nair said the plan to send a spacecraft to orbit the moon, however, remains on course. He said a spacecraft will be put into orbit in the latter half of 2005.
Aug 11, 04: To facilitate INTRA-solar system travel, NASA has committed itself to the study of a number of far-out propulsion methods. Researchers are hoping the space agency's new Propulsion Research Center will help scientists move at least some of those new methods from the theoretical to reality.
. . Among the more promising future propulsion technologies is aerocapture. Much like aerobraking, which a number of NASA spacecraft including Mars Odyssey have used to slow themselves upon arriving at their target worlds, aerocapture is intended to allow a spacecraft use a planet's atmosphere to alter its flight trajectory. But where aerobraking requires multiple orbits and repeated burns by a spacecraft's engine, aerocapture is expected to put a vehicle in orbit after one pass without consuming one drop of fuel. "You have a heat shield, you do the maneuver, and in 30 minutes, you're in a circular orbit." This could save about 40% of mass in propellant --that would be better spent on scientific instruments.
. . Two other propulsion methods: solar sails and the next generation of ion engines.
. . Both Johnson's team and the Marshall-based propulsion center are exploring tether-based technologies to swing spacecraft on their way. The spinning Momentum eXchange/Electrodynamic Reboost (MXER) tether, for example, could sling spacecraft into higher orbits or out on interplanetary trajectories without the need for pesky - and heavy - upper stages. "It's maybe 10 to 15 years out."
. . They're looking at approaches for fission-based nuclear engines.
. . Engineers are evaluating different ways of converting heat from a reactor to power an ion engine or gas-based thrusters. An effective fission system could provide up to 10 million times the energy density generated by the chemical reactions employed on NASA's space shuttles, with one soda can of uranium matching the power of 100 shuttle external tanks. A nuclear reactor is slated to power the electric propulsion system for the Jupiter Icy Moons Orbiter (JIMO) under the space agency's Project Prometheus.
. . Researchers are also studying the possibility of using high-powered plasmas --electrically charged gas.
Aug 11, 04: NASA said it is moving ahead with plans to send a robot to the rescue of the aging Hubble Space Telescope. The leading candidate is a clunky contraption named Dextre that bears little resemblance to movie-inspired visions of a robot.
. . A final decision won't be made until next summer on whether to launch the two-armed Dextre —-short for dexterous [probably pronounced Dexter]-— or any other robot to Hubble's rescue in 3 1/2 years. But already, it looks as though the Canadian Space Agency's robot could accomplish most if not everything that spacewalking astronauts were meant to do. Dextre was originally designed for handiwork at the international space station.
. . "As it turns out, we haven't found any tasks that I would characterize as being outside the capability range of the robot." But some of the doors on the 14-year-old telescope could be warped; one was misaligned and difficult for an astronaut to close a full decade ago. He said the guiding principle is, "Do no harm."
. . Among the most pressing tasks: installing fresh batteries and new gyroscopes to keep it stabilized and replacing two science instruments with more advanced cameras. Engineers are just now looking at whether a robot could fix a 7-year-old spectrograph on Hubble that shut down last week.
. . The goal is to give Hubble five years of life beyond any repair mission. Without help, the on-board batteries will probably be the first to go, in 2007 or 2008.
. . If Dextre is, indeed, picked for the job, it's uncertain whether the one already built for space station use would be sent to Hubble or whether a replica would be fashioned. The robot is supposed to be launched to the space station in 2007, to supplement the Canadian-built robotic arm already there and to handle the more adroit chores.
Aug 5, 04: Our solar system may be unique after all, despite the discovery of at least 120 other systems with planets, astronomers said. Most experts thought that planets formed out of dust. "This dust coagulates and forms small rocks and the rocks combine and form small bodies and then those bodies form things like Earths", he said. "The Earths collect and accrete gas and then they form giant planets like Jupiter. That is one model." But so far no one has found a planet outside our solar system that looks like it formed that way.
. . "Then there is a second model that has been suggested specifically for the formation of giant planets like Jupiter. You start with a gas disk and this disk becomes unstable and it breaks up into large clumps and those clumps are the things that form giant planets."
. . It could be our solar system formed in the first way and most of the others formed in the second way, Livio said. Either way, it is time to start thinking about the possibility that our system is unique or at least unusual.
Aug 2, 04: When Venus crossed the Sun June 8, '04, showing up as a clear black dot to the delight of millions of skywatchers around the world, astronomers noted something less obvious: The amount of sunlight reaching Earth dipped by 0.1% for a few hours.
. . During a stretch of intense solar activity last October, when several huge sunspots generated a record-breaking string of solar flares. At one point, sunlight dimmed 0.3% for about four days, due mostly to three large sunspot groups.
. . It's comparable to the decrease that scientists estimate occurred from roughly 1645 to 1715. During a broader period, from the 1400s to the 1700s, Europe and North America were plunged into what came to be called the Little Ice Age. "For a period of about 50 years, there were almost no sunspots", Rottman said in a telephone interview. "The total amount of radiation was, we assume, about three-tenths of 1% less" than in normal periods of solar activity.
. . If you've been paying attention, that might sound backward. Rottman's team measured a decrease in sunlight when Venus transited the Sun, and similar decreases are recorded when sunspots are present. So why would there have been less radiation in the late 1600s when there were very few sunspots? Rottman explains:
. . Sunspots indicate greater solar activity in general. While they do dampen sunlight while on the face of the Sun, they are surrounded by intensely bright regions called "faculae" or "plage." When sunspots are on the limb of the Sun -- just rotating onto or off of the face -- the plage are prominent from our vantagepoint, creating a significant increase in radiation that far outweighs the dip of radiation caused by the rest of the sunspot's transit. A lack of sunspots indicates inactivity in the Sun, and less radiation overall.
. . The reduced solar activity of the 1600s and 1700s is called the Maunder minimum. Nobody knows for sure why it occurred or whether it will happen again anytime soon. In fact, the whole concept remains controversial, because it's not clear how well astronomers were counting sunspots during the Maunder minimum. And the exact tie to climate is not understood. Most tend to agree, however, that there was a distinct lack of solar activity.
July 23, 04: Surface water on Mars existed across a significant span of time, not just for years but eons, suggest new findings made by NASA's Mars rover Opportunity. It's found a "razorback", a ridge of thin, jagged vertical plates sticking up at the edge of a flat expanse of bedrock.
. . The team suspects that the ridge is a layer of rock that formed when earlier layers of rock cracked, and mineral-laden water percolated through the cracks leaving deposits behind, forming veins, or "fracture fill". Those deposits formed rock harder than the surrounding material, so as the rock eroded away it left this harder ridge behind.
July 23, 04: The Cassini space probe has observed lightning in Saturn's atmosphere. Scientists now hope to use the same method to detect lightning on Saturn's large moon, Titan.
. . Cassini's magnetospheric imager has also detected a new radiation belt around Saturn's rings. The planet's main radiation belt extends far outside the main ring system. The new radiation belt sits within the rings and extends right around the planet.
. . One new hypothesis suggests that the oceans may be covered from view by some sort of hydrocarbon fog.
July 19, 04: Jupiter/Saturn: Researchers modeled 50,000 what-ifs of internal structure using real data from the two planets and lab experiments that show how material behaves under extreme pressure. They found Saturn has a huge core and Jupiter may have none.
July 15, 04: NASA is set to launch a spacecraft to Mercury in August for the first time in 30 years, with a probe meant to orbit the heavy-metal planet while it maps its surface and looks for frozen water in shady polar craters.
. . The Messenger spacecraft is set for launch Aug. 2 on a seven-year journey that will loop around Earth, Venus and Mercury, getting a boost from the gravity of these three planets to guide it to a Mercury orbit for a one-year mission.
. . Messenger won't make the first Mercury fly-by until 2008 and will not begin its main mission until 2011. The roundabout route is geared to saving the cost and weight of the extra fuel required for a quicker trip. The last time the NASA sent a spacecraft there was in 1974 and 1975, when the Mariner 10 probe made three close passes, returning detailed data on less than half of Mercury's surface.
. . By contrast, Messenger will carry seven scientific instruments, including cameras, spectrometers to figure out what chemicals are present, a magnetometer to learn more about Mercury's magnetic field and an altimeter to measure its topography. It is so dense that scientists believe at least two-thirds of it must be made up of iron.
. . Still, astronomers wonder if there is frozen water somewhere on the surface despite the heat. Unlike Earth, Mercury does not spin on a tilted axis, which means a crater at its north or south pole would be in permanent shadow. And Mercury's ultra-thin atmosphere does not transport heat from the equator to the poles.
July 8, 04: The first of an unprecedented series of powerful solar storms that punished Earth late in 2003 is now at the edge of the solar system, some 13 billion km away, poised to move beyond the farthest manmade object in the cosmos.
. . Another storm stole air from Mars, hinting at where water that was once abundant on the red planet might have gone.
. . All the eruptions were spawned by huge, magnetically unstable sunspots during a two-week stretch of heightened solar activity unlike anything on record. Expanding clouds of charged particles known as coronal mass ejections (CMEs) raced into space.
. . A few of the CMEs moved abnormally quickly, reaching Earth in less than a day and helping scientists to later determine a speed limit for the electrified gas clouds. One set a new space speed record of 2,235 km per second.
. . Later this year, the blast should reach the true edge of the solar system, some 4.8-6.4 billion km beyond Voyager 1. There the storm will meet head-on with a wave of interstellar particles at what's called the heliopause. Radio disturbances caused by that interaction then might be picked up by the Voyager craft, giving scientists their first measurement of where the edge really is. Stone said the interaction will also temporarily push the Sun's influential boundary another 644 million km into space. It should rebound within a year or two.
. . If humans travel back to the Moon or on to Mars, they would be at great risk from solar storms unless housed in highly protective habitats or spacecraft. High doses of radiation from a storm -- say, during a spacewalk -- could be lethal. Lower doses over time might damage the central nervous system.
July 8, 04: Saturn's rings are a lot dirtier than originally believed, according to new observations by the Cassini spacecraft that show that the inner regions are packed with rock and mud. "We've known for decades the rings are mostly made of water", said Larry Esposito of the University of Colorado. "Now we know the amount of water varies, increasing toward the outer edge of the rings. Cassini's cameras were not powerful enough to resolve the individual icy boulders and smaller particles thought to make up the rings.
. . Cassini images made in ultraviolet light have been combined with infrared pictures --all taken during the June 30 pass through the ring plane. The ice is also thought to contain other frozen substances such as ammonia. Esposito said the gunk in the rings has a UV signature similar to dark material on Saturn's moon Phoebe.
July 4, 04: The Cassini spacecraft returned data that showed it has survived some 100,000 impacts with space dust particles the size of smoke as it flew through Saturn's ring planes during the orbit insertion maneuver.
July 2, 04: An eruption of atomic oxygen spotted around Saturn by the Cassini spacecraft suggests that the planet's iconic rings are eroding and could be gone in 100 million years, NASA scientists said. Cassini scientists theorize that the atomic oxygen is evidence of a collision between objects in Saturn's "E-ring", which are largely made up of ice and could have released the gas as they broke apart.
. . "The implication is that within 100 million years time this process would erode the entire E ring, assuming there was no replenishment."
July 1, 04: Mars was not only awash with water, it also once had rainfall, according to a French study. The evidence comes from infra-red imaging, which probed under dust deposited over the millions of years and found dense networks of dry valleys, whose branching bear the hallmarks of having been carved out by rain.
. . The research could prompt a rewrite of the Martian history books, for it suggests the planet had a longer "summer" than anyone thought. The conventional theory is that Mars had a balmy climate during its infancy, a period called the Noachian era, in which vast volumes of water flowed on its surface, cutting valleys and eroding the craters left by asteroids.
. . Then, around 3.6 billion years ago --coincidentally, just when the first signs of life emerged on Earth-- the planet froze, entering the so-called Hesperian epoch, which lasted around half a billion years. What remained as water has almost always been locked up as ice, either at the poles or (so it is hoped) close to the surface, according to this theory. The theory contends though that the rain-carved valleys date from near the end of the Hesperian --at a time when the temperature was, supposedly, far too cold to permit precipitation.
June 27, 04: The wok-shaped Huygens probe, developed by the European Space Agency, will be released from Cassini in December and will enter Titan's atmosphere in January. Under 3 meters in diameter and weighing 320 kg, its six instruments will investigate Titan's atmosphere and then its surface, if it survives the impact of landing after a 2 1/2-hour descent by parachute. The probe will radio data back to Cassini up to a maximum of 30 minutes after touchdown. By then, either its batteries will have failed or Cassini will have passed over Titan's horizon.
June 25, 04: Scientist Bradley C. Edwards has an idea that's really out of this world: an elevator that climbs 62,000 miles into space. A Russian scientist, Konstantin Tsiolkovsky, envisioned it a century ago. Edwards thinks an initial version could be operating in 15 years, a year earlier than Bush's 2020 timetable for a return to the moon. He pegs the cost at $10 billion, a pittance compared with other space endeavors. NASA already has given it more than $500,000 to study the idea, and Congress has earmarked $2.5 million more. Edwards said he probably needs about two more years of development on the carbon nanotubes to obtain the strength needed. After that, he believes work on the project can begin.
. . Edwards' elevator would climb on a cable made of nanotubes — tiny bundles of carbon atoms many times stronger than steel. The cable would be about three feet wide and thinner than a piece of paper, but capable of supporting a payload up to 13 tons. Different methods of producing carbon nanotubes are moving forward, even to the point of a new process that spins the material in similar fashion to how rope is made. The cable would be attached to a platform on the equator, off the Pacific coast of South America where winds are calm, weather is good and commercial airplane flights are few. The platform would be mobile so the cable could be moved to get out of the path of orbiting satellites.
. . The elevator would be powered by photo cells that convert light into electricity. A laser attached to the above platform could be aimed down at the elevator to deliver the light.
. . "The major obstacle is probably just politics or funding and those two are the same thing", he said. "The technical, I don't think that's really an issue anymore."
There are 36 factors that affect the tides, from the Earth's proximity to the sun and the moon to the moon's angle in relation to the equator. Every 19 years, those factors line up just so — creating the lowest low tides and the greatest differences between low and high tides.
June 24, 04: Phoebe's mass was determined from precise tracking of the spacecraft and optical navigation, combined with an accurate volume estimate from images. The measurements yield a density of about 1.6 grams per cubic centimeter (100 pounds per cubic foot), much lighter than most rocks, but heavier than pure ice at approximately 0.93 grams per cubic centimeter (58 pounds per cubic foot).
. . Phoebe is very cold, only about 110 degrees above absolute zero (-163 degrees Celsius, or -261 degrees F), the observations show. Even colder nighttime temperatures suggest a fluffy, porous surface layer.
June 23, 04: Images snapped by NASA's Cassini spacecraft show that Saturn's moon, Phoebe, is not an asteroid but a 4.5-billion-year-old primordial body from the solar system's outer reaches, scientists said. High-definition photographs as well as spectrographic and thermal images taken during Cassini's June 11 fly-by revealed that Phoebe likely is made up of ice, rock and carbon compounds similar to those seen in Pluto and Neptune's moon, Triton.
. . Cassini's spectrometer picked up signs of water-bearing minerals, carbon dioxide and organic material
June 21, 04: The leading theory for the Moon's formation has a Mars-sized object slamming into Earth about 4 billion years ago, shortly after our planet formed. But if it was nearby, why did it hit after Earth formed and not sooner?
. . The Mars-sized impactor formed at the same distance from the Sun as Earth in a gravitationally stable spot known as a Lagrangian point, then drifted out of that birthplace --thanks in part to collisions-- to set up a crash course in satellite development.
. . The scenario was recently proposed by astrophysicist J. Richard Gott and mathematician Edward Belbruno, both of Princeton University.
. . The Lagrangian points named L4 and L5 sit along Earth's circular path around the Sun. They move as Earth moves. Each forms an equilateral triangle between itself, the Sun and Earth. Gravity from the Sun and Earth combine to create a state of equilibrium at each of the two points.
. . Gott and Belbruno poured the raw material for planet formation into a mathematical model, then theoretically estimated what happened at L4 and L5. Material tended to collect there and the locations yielded similar results.
. . "After about 30 million years, a Mars-sized object results. At about 30 million years, its velocity is sufficient for it to just barely leak out of the L4 region of stability."
. . It might be possible to investigate the new piece of the theory by sending a space probe to one of the Lagrangian points.
June 18, 04: Scientists are exploring the idea of a robotic spacecraft that would visit Uranus around 2014 and continue on to the Kuiper Belt (KOY-per). The project would be patterned after NASA's New Horizons spacecraft, which is scheduled to begin a mission to Pluto and its moon, Charon, in early 2006. It would use a gravity assist from Jupiter, then slip by Uranus en route to multiple Kuiper Belt Objects (KBOs).
. . For the New Horizons probe already on the books, its Earth departure for Pluto by way of Jupiter occurs in January 2006. After launch, the spacecraft is to arrive at Jupiter just over a year later. New Horizons would pass through the Jupiter system at 50,000 mph, ending up on a path that could get the spacecraft to Pluto and Charon as early as 2015.
. . New Horizons II would zip by Uranus at a very special time, Stern said, at equinox when the planet, all of its satellites and ring systems, as well as magnetosphere, could be observed in unprecedented fashion. "That only happens every 42 years."
. . 1999 TC36, a large KBO, is circled by a smaller satellite. "It's like a little compact miniature of the Pluto-Charon system. We are just starting to appreciate that there are swarms of these objects that are different from one another."
June 17, 04: A description of the comet Wild 2 —-pronounced "vilt"-— and several analyses of the mission to study it are reported in the journal Science. They saw two different kinds of craters, probably created when other space bodies slammed into the comet. One type has a rounded central pit and a rough surrounding terrain, presumably because material was ejected during the impact. The other type has a flat floor and nearly vertical cliffs.
. . It has no known peers in the solar system. More than a dozen jets of material shoot out from its insides. Dust swirls around the comet in unexpectedly dense pockets. The comet is only about 5 km wide. If you stood on the surface, you could jump into orbit.
. . Only two other comets have been seen up close, but both appeared fairly smooth and were nowhere near so heavily cratered. Nor do the pockmarked surfaces common to asteroids and moons bear much stylistic resemblance to the shapes seen on Wild 2.
. . Yet Wild 2 is not a fractured pile of rubble that would all fly apart when hit, as some astronomers expected. Brownlee: "We're sure this is a rigid material because it can support cliffs and spires." Spires shooting up from inside craters "looks like Monument Valley in Arizona", Brownlee said at a press conference today. They likely formed as material around them eroded, indicated that the comet has lost about 100 meters of its surface since birth... about 1 meter since 1974. He suggested the consistency of the comet is something like freeze-dried astronaut ice cream. That suggests the "footprints" and other depressions on Wild 2 are in fact impact craters.
. . Built-up internal pressure and "steam explosions" might be responsible for some of the surface features.
. . In another baffling surprise, Brownlee said, dozens of photos show no small craters on Wild 2, only the large craters that are presumably billions of years old. Perhaps small craters erode away, he said.
. . He is also intrigued by the utter lack of similarities between Wild 2 and Phoebe, a fairly small moon of Saturn recently imaged up close by the Cassini spacecraft. Phoebe is thought to be a captured object, having originated --like Wild 2-- beyond Neptune. But Phoebe's gently sloping craters, which are riddled with boulders, resemble those seen on asteroids. And Phoebe has many small craters embedded in larger, older craters. Phoebe is considerably larger than Wild 2 --about 220 km wide-- so self-gravity could have something to do with the differences. And Phoebe has likely never traveled inside the orbit of Saturn, so it probably has not been hit with solar radiation to the extent now experienced by Wild 2.
. .A separate analysis of Stardust data found 20 jets, on both the sunlit side of the comet and, surprisingly, the dark side.
. . The European Rosetta craft, recently launched, will land on a comet in 2014. NASA's Deep Impact will slam a probe into comet Tempel 1 on Independence Day 2005. surprised that the comet is apparently not a loosely cemented rubble pile.
June 14, 04: Potentially disruptive solar storms can't reach Earth in less than half a day, scientists have determined. That means operators of vulnerable satellites, airline officials and power grid managers can expect several hours of warning for any electrical disturbance shot from the Sun.
. . Warnings are provided by NASA's sun-watching SOHO spacecraft and other observations. When space storms approach, engineers put some satellites into sleep mode, airlines are rerouted away from polar regions where more radiation leaks through the atmosphere, and major electrical lines are safeguarded against overloads.
. . Initial radiation from a solar flare, including X- rays, travels to Earth at the speed of light. But the charged particles present greater hazards to the electrical systems aboard Earth-orbiting satellites.
June 14, 04: Saturn's moon, Phoebe, has been battered for billions of years by interplanetary debris, and the signs of past violence are clear in images snapped by a spacecraft headed for orbit around the ringed planet.
. . Phoebe probably was pulled into Saturn's orbit around the time the solar system formed, about 4.5 billion years ago, he said. This means this moon might be related somehow to comets or objects from an area at the outer fringe of the solar system known as the Kuiper Belt.
. . The latest images were snapped when Cassini drew to within 2,060 km of Phoebe. That is much closer than the last look taken by earthly instruments, a 1981 glimpse by the Voyager probe in 1981, which viewed Phoebe from 1.4 million miles away.
. . Cassini's pictures of Phoebe show a dark and lumpy body, "kind of like a golf ball with all the dimples really exaggerated." It reflects only about 6% of the light that reaches it. The new images show what appear to be layers of dark and light material. "There's dark material which appears to have light material underneath it", Johnson said. "We have strong suspicions based on telescopic data that the light material is water ice, but there may be other volatiles there, too."
. . Cassini is expected to conduct 76 orbits around the Saturn system and execute 52 close encounters with seven of Saturn's 31 known moons.
. . Phoebe --about 220 km wide-- rotates every nine hours 16 minutes. Its orbit is outside the plane of Saturn's equator and, curiously, it circles the planet in the opposite direction to its other moons. Its darkness, too, is a puzzle. One theory is that its surface could be smeared by an organic compound called tholin, a sticky, dark red residue known to cause the brownish haze of Saturn's largest moon, Titan.
. . "Looking at those big 50 km craters, one has to wonder whether their impact ejecta might be the other tiny moons that orbit Saturn on paths much like Phoebe's."
. . Radar probed the surface down to nearly 20 cm (8 inches). Cassini also recorded ultraviolet and infrared light. Phoebe's gravitational effect on the spacecraft was noted. Astronomers expect to determine the moon's exact mass and density, create a detailed global surface map, and figure out a lot about what it's made of.

. . Huygens: how' -hens, but the how is almost Ha-uu, & the hens is almost kkkens.

June 4, 04: A space rock the size of a large mountain hit 1.8 billion years ago and dredged up part of Earth's lower crust, essentially turning a bit of the planet inside out, a new study concludes. Earth's upper crust is about 35 km thick. Scientists have debated how deeply into the crust the shock wave from a large asteroid could penetrate. All the way to the next layer, it appears.
. . The evidence comes from a crater in Sudbury, Ontario. The crater was initially more than 200 km wide. Most of the crater was long ago folded into the planet or eroded away. But a section is exposed, revealing minerals and other features that can be compared to more recent craters that are more intact. From all this, scientists gleaned clues to the catastrophic impact.
. . It appears an asteroid about 10 km wide hit the planet at more than 40 km per second. "The impact punched a hole to the very base of the crust and the meteorite itself was probably vaporized." A plume of superheated rock from deep down surged upward and landed on top of the impact site, creating the melt layer visible today.
. . In the top layers of the Sudbury structure, the team found relatively high concentrations of iron, nickel and platinum, stuff that is more common in the lower crust of the planet than in the upper crust.
June 2, 04: Without the fuel to maintain a proper orbit, low satellites eventually plunge to a fiery death in the atmosphere.
. . Orbital Recovery's vehicle, dubbed ConeXpress Orbital Life Extension Vehicle, is an ion-propelled spacecraft designed to fit into what until now has been empty space aboard an Ariane 5 rocket. The space tug, which is expected to conduct its first service call in 2007, is aimed at the telecommunication satellite industry, which depends on spacecraft in geosynchronous orbits. About 83 telecommunications satellites orbiting Earth through 2011 whose missions could be extended by ConeXpress. Those high- end satellites, he added, were launched along with many others in the late 1980s and early 1990s and are approaching the end of their planned mission lifetimes.
. . Once the space tug arrives at a satellite, it uses a docking probe to attach itself to the kick motor of the target craft, then it fulfills all the spacecraft's navigation and propulsion needs. Altogether, ConeXpress should be able to increase a single satellite's operational lifetime by up to a decade.
June 2, 04: NASA's chief told the nation's astronomers he is optimistic robots could repair the Hubble Space Telescope and said the space agency is seeking proposals to do just that. The audience of astronomers —-about 1,000 of them-— erupted into applause. O'Keefe said the goal would be to service the big space observatory by the end of 2007. Spacewalking astronauts were supposed to install new batteries and other gear on Hubble in 2006. But that shuttle mission was canceled.
. . O'Keefe has a very speedy timetable planned. The robotic proposals must be completed by mid-July; NASA will evaluate them for six to eight weeks with a Labor Day target. But O'Keefe noted the robots' primary responsibility would be to successfully rendezvous with the telescope and then install a module that would guide the spacecraft back into Earth's atmosphere, steering it away from cities and other vulnerable targets. He stopped short of promising repairs, preferring to wait to see what the engineers offer in their proposals.
. . The James Webb Space Telescope, set for launch in 2011, will focus on the infrared and outdo Hubble with a mirror more than double its size. Astronomers have said they would be at a loss if Hubble is abandoned and the Webb is lost in a rocket explosion or has crippling design flaws.
May 20, 04: Most planetisimals orbit the Sun between Mars and Jupiter. But a handful cross the path of Earth on elliptical trajectories. One had previously been found to move completely inside the annual path of our planet.
. . The newfound rock, named 2004 JG6, is currently between Earth and Venus and orbits the Sun every six months. But its elliptical path takes it well inside the circle of Venus and even inside Mercury's path. On average, it is closer to the Sun than Venus. It passes within 48.3 million km of the Sun.
. . The planetisimal is probably no more than 500 meters and 1 km wide. There may be 50 comparable in size to 2004 JG6 orbiting entirely inside Earth's travels. But because they spend much of their time in the glare of the Sun, they are hard to find.
May 3, 04: On Sept. 29, 2004 a planetisimal the size of a small city will make the closest known pass of such a very large space rock anytime this century. Toutatis is about 4.6 by 2.4 km.
. . While not dangerous for now, Toutatis is incredibly strange. And scientists are quite familiar with it, having bounced radar off the tumbling stone on previous flybys to generate computer renderings of its weird shape and movement.
. . Toutatis looks something like a dumbbell hurtling awkwardly through space. It has a crazy rotation that makes normal days impossible. Scientists can't explain the shape or the spin, but they're eager to learn more in September when, during the close pass, even backyard skywatchers will be able to spot the "asteroid".
. . Toutatis' 4-year trek around the Sun ranges from just inside the Earth's path out to the main asteroid belt between Mars and Jupiter. The asteroid visits us every four years. This fall, it will zoom by our planet within 1.5 million km. That's close by cosmic standards for an object that could cause global devastation.
Apr 26, 04: Saturn's moon Iapetus is two-faced. One half is dark as coal and the other is as bright as fresh linens.
. . Iapetus is 1,460 km wide and circles Saturn at a distance of about 3.6 million km. Like Luna, Iapetus' rotation and orbit are in lockstep, both taking 79 Earth- days, so that it always shows the same face to Saturn.
. . The side of Iapetus that always faces forward as it moves along its orbital path reflects just 5% of the sunlight that hits it. The trailing hemisphere reflects 50%. The debris might be bits of another moon, Phoebe, whose whole surface is relatively dark. The material might be kicked up from Phoebe by small meteor impacts, the thinking goes.
. . Astronomers had suspected ammonia might be present in the moons of Saturn, but it has never been directly detected. The radar observations seem to offer the strongest evidence yet for its existence.
. . "Another surprise is that the radar system sees Iapetus as a uniform object, meaning no difference between the light and dark sides." That could mean that on the dark side there is merely a thin coat of some darkening material over the ammonia-laden water ice, like an inch of dirt atop clean snow.
The Soviet exploration of Venus, from 1961 to 1984, was an impressive effort. Successful Soviet missions to Venus included 3 atmospheric probes, 10 landings, 4 orbiters, 11 flybys or impacts, and 2 balloon probes of the clouds.
Apr 20, 04: If humans ever go to Mars, they may find electric mini-tornadoes that could make toxic dust stick to their spacesuits, researchers said. They've already detected whirlwinds and duststorms on Mars, and they figure they may generate electric charges just as small tornadoes on Earth do. On Mars, jumbo-sized dust devils can range up to 500 yards across with heights of several thousand yards, Farrell and his fellow researchers said. As on Earth, martian mini-tornadoes likely can produce an electric field of 4,000 volts per meter --not enough to power a toaster, but certainly enough to create dangerous static cling with spacesuits and equipment. "(The martian dust) won't weigh it down, but you're going to have a heck of a time getting it off, and at this point we're not sure that Mars dust is all that healthy", he said.
. . A future robotic probe tentatively set for 2007 is expected to analyze the dust to analyze possible toxicity of martian dust.
Apr 20, 04: The most detailed images ever made of Saturn's moon Titan, by the Keck Telescope in Hawaii, reveal surface features in unprecedented clarity. What emerges --in addition to other science-- are light and dark regions that indicate areas of high and low reflectivity, which suggests differing compositions on the mostly mysterious moon. The results support other tantalizing hints that the huge moon is at least partly covered by giant seas of liquid hydrocarbons such as methane and ethane. Though too cold to support life as we know it --minus 179 C-- the moon is expected to contain interesting prebiotic chemistry.
. . Given this limited knowledge and the impending arrival of the Huygens probe, astronomers around the world are mounting multiple ground-based efforts to stretch telescoping to its limits and provide as much information as possible over the next few months.
. . Haze over Titan's south pole is evident between 30-50 km altitude and dissipates seasonally in Titan's long year, which lasts about 29.5 Earth-years. Across a broad part of the northern hemisphere, haze is visible high in the stratosphere of Titan, about 150 km up. The stratospheric haze is absent from the southern hemisphere.
Apr 15, 04: Pluto has had its rotational period slowed to six Earth-days by its companion, Charon. Sedna spins on its axis once every 20 Earth-days, or perhaps even more slowly, making the presence of a moon practically inevitable, Brown had thought. So shortly after the discovery, Hubble was pointed at Sedna. "Much to our surprise, there's no satellite." More likely, Brown figures, is that the satellite is darker than expected and simply didn't show up. "Even though it's quite large, it could be quite dark", he said. "We still very strongly believe there is or was a satellite."
. . Other possibilities include the notion that Sedna once had a moon, which slowed the planetoid's rotation, but the moon was destroyed by an impact with another cosmic body or was pulled away by a close encounter with another planetoid.
. . The rotation of Sedna, officially named 2003 VB12, was determined by noting changes in brightness from its surface.
If an "asteroid" was confirmed to be on a catastrophic collision course with Earth, the experts said it would take about 30 years to get ready to do anything about it. The Space Shuttle's main engines and the fuel contained in the large external tank could successfully deflect a 1 km object if it were applied about 20 years in advance of a projected collision.
The Milky Way galaxy, which holds billions of stars and is home to our solar system, also houses stars traveling more than 300 kps --1/1000 the speed of light.
. . Barnard's Star, discovered in 1916, is the second nearest to our Solar System at 5.97 light years, only triple star Alpha Centauri is closer.
. . It's approaching us rapidly at 87 miles per second, so that the combination of both indicates a space velocity of of about 103 miles per second. According to Burnham, the star will reach a minimum distance of less then 4 light years in about 8,000 years.
. . Barnard's star is a red main-sequence dwarf of apparent visual magnitude 9.56 and absolute visual magnitude +13.4. Its luminosity is only about 1/2500 that of our sun. According to Burnham, J.C. Duncan has estimated the star's mass as 16% that of our sun, and its diameter at 224,000 km, or about 1/6 that of Sol. Its spectral type indicates that Barnard's Star is cool: Only about 3200 K.
. . Barnard's Star is approaching Sol rapidly at 140 kps and will get as close as 3.8 light-years around 11,800 CE. Like other red dwarfs, however, it is not visible to the naked eye.
. . Substituting Barnard's Star for Sol would give the Earth such a dim and very red Sun that it would only be 100 times brighter than the full moon, and so Earth would freeze solid at the surface.
. . In order to be warmed sufficiently have liquid water at the surface, an Earth-type rocky planet would have to be located very close to such a cool and dim red dwarf star like Barnard's, at around 1/50th the Earth-Sun distance (or 0.02 AU). At distance, such a planet would probably be tidally locked --with one side in perpetual day- - and race around the star in only about 2..6 days. Some have suggested that any rocky planets that formed around Barnard's are likely to be sparse in the heavier elements of the atomic table, and that there may be a greater probability of gas giants made mostly of hydrogen and helium in cold, outer orbits.
Apr 6, 04: Saturn's moon Titan passed in front of the Crab Nebula, which shines brightly in X-rays, on Jan. 5, 2003. While Chandra routinely images X-rays directly, in this case it captured Titan's shadow in a technique likened to medical X-rays.
. . The Crab Nebula is the remnant of a supernova explosion that was observed to the year 1054. "This may have been the first transit of the Crab Nebula by Titan since the birth of the Crab Nebula." The next similar conjunction will take place in the year 2267.
. . The diameter of the X-ray shadow cast by Titan was larger than the diameter of its solid surface. The difference in diameters --about 880 km-- gives the height of the X-ray absorbing region of Titan's atmosphere. The extent of the upper atmosphere is consistent with, or slightly (10-15%) larger, than that implied by Voyager I observations made in radio, infrared, and ultraviolet wavelengths in 1980.
. . "Saturn was about 5% closer to the Sun in 2003, so increased solar heating of Titan may account for some of this atmospheric expansion." Titan's atmosphere, which is about 95% nitrogen and 5% methane, has a pressure near the surface that is 1.5 times that in Earth's atmosphere sea level pressure.
Apr 5, 04: NASA is reviewing over two dozen proposals to extend the useful scientific life of the Hubble Space Telescope, as well as safely dispose of the Earth orbiting observatory at the end of its life in space. An attachable package of batteries and gyroscopes that can be mounted on Hubble, done via robotic servicing, is being considered.
. . The observatory's retrieval by a space shuttle at the end of its mission is no longer an option. It is now headed for an uncontrolled reentry into Earth's atmosphere no earlier than the year 2013. Hubble's projected battery life is the principal limiting factor for overall observatory lifetime.
. . In one scenario, a propulsion stage would be lofted on an expendable launch vehicle. It would then rendezvous, capture, and dock with the HST. Once those actions are complete, the telescope can be nudged into a controlled reentry or boosted to the higher safe parking orbit. To do so requires use of a still-to-be-built and checked out propulsion module that would be attached to Hubble. [heck, I thot of that.... And how 'bout a ion engine to replace or suppliment the thrusters?]
The Phoenix Mars lander in 2007 is equipped to dig down in the martian topside and probe for ice. "It will be very important to get down and see if ice is really there. Finding organic compounds in that ice would be another huge smoking gun for life." The follow-on Mars Science Laboratory in 2009 could carry sophisticated drilling gear to help understand what lies beneath the martian landscape.
Mar 31, 04: Saturn's moon Titan might be one of the most out-of-this world places to hang ten, according to new computer modeling that suggests a given wind could generate waves there that are seven times taller than on Earth. Because Titan's gravity is about one-seventh that of Earth, any wind-driven waves would behave differently than they do here. Waves on Titan will generally appear to move in slow motion." ...and would be more widely dispersed than on Earth.
. . Scientists aren't sure if Titan has seas, but they suspect it does based on hard-to-interpret telescopic observations. The oceans would be made mostly of ethane and methane. The Titan model incorporates wind speeds up to a modest 5 meters per second. "We do not know much about the surface winds on Titan, although early models suggest the sustained wind speed at the surface is likely to be low", Ghafoor explained. The model includes fetches up to 1,000 km.
. . The Cassini mission to Saturn carries the Huygens probe, which will plunge through the atmosphere and land on Titan's surface --whatever it's made of-- early in '05. If Huygens lands in a sea, it could float and transmit data for up to two hours. The probe has instruments that could measure the height and frequency of any waves and the liquid's composition. With sonar, it could measure the sea's depth. Its camera might even return the first pictures of an extraterrestrial sea.
Mar 29, 04: A trio of research teams independently probing the Martian atmosphere for signs of methane have found it, a combined discovery that opens the door for a host of theories as to how the smelly gas got there. The European Mars Express mission detected Mars methane while orbiting the planet. "It's of course very exciting and quite a surprise."
. . Among the most tantalizing, if not very likely, of scenarios, scientists say, is the possibility that the Mars methane could be the byproduct of some form of microbial life. But a safer bet, they say, centers on the geology of Mars, including anything from volcanic activity to long-ago impacts of methane-carrying comets.
. . Since methane has a relatively short lifetime on Mars for atmospheric gases, about 300 years or so, scientists believe there must be some process at work to keep replenishing its concentration in the atmosphere --about 10.5 parts per billion.
. . "Volcanism has not been ruled out as a modern phenomena on Mars." Nothing so explosive as an eruption is needed to expel the gas. It could possibly seep out through gentle, consistent hydrothermal activity.
Martian minerals: salty chemical forms of sulfur known as sulfates... such as: Jarosite, a hydrated iron sulfate, typically found in acidic lakes or such as hot springs. Magnesium sulfate kieserite --similar to epsom salt-- and bromide salts, are evaporite minerals, and found on Earth in regions where seas evaporate over time.
Mar 26, 04: Earth has acquired a "quasi-moon" -- an "asteroid" that will encircle our planet for the next couple of years while it orbits the sun on a horseshoe- shaped path, according to a report in New Scientist. The 'tisimal, 2003 YN17, "is probably a chunk of debris" from an impact between a larger space rock and the surface of the moon. Its orbital plane is roughly the same as the earth's, but its unusual path, compounded by a corkscrew- like track, means that sometimes it is ahead of us and sometimes it is behind. "Since 1996, its path has taken it round the earth, making it a quasi-satellite. This phase will last until 2006." Two other "quasi-moons" --temporary fellow-travellers that loop around the earth for while as they girdle the sun-- have been spotted in recent years: Cluithne and 2002 AA29.
Mar 25, 04: Odd spiraling gorges etched deep into the polar ice caps of Mars have stumped scientists for decades. The huge arcing troughs radiate outward like arms of a pinwheel, creating an overall shape that visually and mathematically resembles hurricanes, spiral galaxies and even some seashells.
. . Now there is an apparent solution to the mystery, put forth by Jon Pelletier of the University of Arizona in Tucson.
. . The tilted planet causes ice on one side of a crack to heat and vaporize, deepening and widening the crack. Then the water vapor hits the shady, colder side of the growing canyon and refreezes. Eventually, chasms more than a km deep developed, and they cover hundreds of kms of the polar regions.
. . But only on Mars, it seems. Characteristics unique to the red planet --its thin atmosphere, chilly climate and specific planetary tilt-- make it the only known place in the solar system where the ice spirals occur.
. . The ever-expanding arms follow a pattern known as a logarithmic spiral, arms tight at the center and growing rapidly farther apart as they splay out. It is a common pattern in nature, repeated in hurricanes (when viewed from above), & the seashells of the chambered nautilus.
Mar 25, 04: If humans are to walk across Mars safely, far more data is needed about the hazardous environments of the red planet, aerospace engineers and analysts told a presidential commission. Toxic materials may exist in the soil. Airborne dust, too, may plague the day-to-day tasks undertaken by an expeditionary crew. Furthermore, little is known about the degree of radiation cascading through the thin martian atmosphere.
. . One toxic metal that appears to be worrisome, McSween (University of Tennessee) said, is hexavalent chromium. "It was the chemical villain in the movie Erin Brockovich", he said. This is the most carcinogenic substance known and causes cancer in lowest concentration of any material yet seen, he added. He is also a Mars Exploration Rover scientist.
Mar 23, 04: Elements that can form chloride or even bromide salts were also revealed by Opportunity's science instruments. This suggests that any possible microbes on Mars would not have had to rely only on relatively inefficient subsurface, geochemical energy, but might have used direct sunlight as an energy source.
. . There are organisms that like sulfates, Clark said, actually using them as an energy source in combination with hydrogen gas in the atmosphere, Clark said. "That gives organisms on Mars a way to live without having to use the Sun and be exposed to the ultraviolet light. That's really good too."
. . Lastly, Clark said that the evaporation that seems to have occurred at Meridiani Planum was a slow process. "So that gives the organisms time to adapt." Salty water can be stable on the surface even with lower atmospheric pressure and colder conditions. Pure water on Mars is currently unstable with respect to temperature and pressure, meaning that the water will boil and freeze when exposed to current Martian surface conditions.
Mar 22, 04: An unprecedented "asteroid" scare in January had astronomers worried for a few hours over a rock that had a 1-in-4 chance of hitting Earth during the next few days. At the time, some of the scientists were unsure who should be notified. The event has prompted NASA (news - web sites) to set up a formal process for notifying top officials in the future of any impending impacts. Astronomers estimate there are about 1,100 "asteroids" larger than 1 km that sometimes inhabit the same general space as Earth. These are the potential civilization destroyers. More than half have been found and some 90 percent are expected to be catalogued by 2008. So far, none are headed our way anytime soon.
March, 04: he Southern African Large Telescope (SALT) will be 12 meters in diameter. It could see a candle flame on the moon. SALT will be the biggest telescope in the southern hemisphere --from where galaxies can be viewed which cannot be seen up north-- including the Magellanic clouds.
Mars sediment contains maybe two to three% hematite. Some areas will be higher, of course.
Mar 18, 04: Russian designers are working on a replacement for the veteran Soyuz spacecraft. The new spacecraft, called the Clipper, will hold a crew of six compared to Soyuz's three. It will have a takeoff weight of 16 tons —- more than twice its predecessor. Unlike the Soyuz, which can only be used once, the Clipper will be reusable and capable of making up to 25 flights. Energiya can build the Clipper in five years if it receives sufficient government funding. Energiya engineers were also working on a huge spaceship for a flight to Mars, set to weigh 660 tons.
Mar 18, 04: A space rock is about 30 meters wide passed just 43,000 km over the southern Atlantic Ocean. That's about 3.4 times the Earth's diameter. It's also just beyond geostationary weather satellites, which orbit at an altitude of 35,900 km.
. . The path of 2004 FH will be bent about 15 degrees by Earth's gravity. An object of this size, where it to take direct aim, would likely break apart or explode in the atmosphere, astronomers say. The result could cause local damage. Something just slightly larger could survive to the surface and destroy a city. The asteroid circles the Sun every 9 months. Astronomers can't say whether the asteroid might encounter Earth in the future.
Mar 17, 04: Mars holds huge reserves of frozen water in its southern pole, according to the first detailed assessment of the data sent back by Europe's Mars Express spacecraft earlier this year. The French-led team say they have spotted frozen water in three forms in the Martian south pole.
. . The first is water ice mixed with "large concentrations" of frozen carbon dioxide (CO2) on a large bright spot on the perennial polar cap -- the cap that is there all year round. Exactly how much of the ice on this bright spot is water rather than CO2 is unclear. A good estimate would be about 15%, the scientists say.
. . The second form is in icy deposits that encrust rugged scarps around the polar cap, and which appear to be free of CO2.
. . But third, the most exciting find is huge icy deposits lying some distance away that seem to be a mixture of water and dust.
. . As for the perennial cap, laser altimeter readings suggest it is a slab between one and three km thick and some 400 km across. The good news is that the bright spot which is mainly CO2 is only a small part of the cap. In the areas adjacent to it, the carbon dioxide ice "might well be restricted to a fairly thin layer, no more than some meters in depth", the authors hope. If so, the implication is that the rest of this large slab comprises dust and water ice, constituting "a significant fraction" of Mars' water reservoir.
. . Mars' north pole has long been considered to comprise mainly of water ice.
Mar 15, 04: A newly discovered dark and frigid world, a bit smaller than Pluto and three times farther away, has emerged as the most distant object in the Solar system. The new KBO, named Sedna after an Inuit goddess, is by far the coldest and most distant object known to orbit the sun. At about 13 billion km from the sun, the temperature on Sedna never gets above minus 240 degrees C.
. . The Spitzer scope found that Sedna is between 1300 and 1,770 km in diameter --about three-fourths the diameter of Pluto-- which would make it the biggest object found in the solar system since Pluto's discovery in 1930.
. . Sedna lies more than three times farther from the sun than Pluto. It follows a highly elliptical path, a circuit of 10,500 years. It loops out as far as 135 billion km, or from 76 to 900 A.U. (times the distance between the Earth and our star). It's travels are even stranger in one sense. Sedna's inclination is 12 degrees; less than that of Pluto.
. . The team also has indirect evidence of a tiny moon that may orbit Sedna, which is redder than all other known solar system bodies except Mars.
. . Scientists can't figure out how Sedna, which is about three-fourths as big as Pluto, came to have such a strange orbit around the Sun. It ranges from 76 astronomical units (AU) when it is closest to the Sun to 1,000 AU when it is farthest. Michael Brown, the astronomer at California Institute of Technology who led the discovery of Sedna, said the most likely scenario involves the Sun having been born in a star cluster, and several stars that were then closer to the solar system --still more than 10,000 AU away-- were responsible for ejecting objects like Sedna.

. . The round world is currently three times farther away than Pluto from the Sun, a distance that expands even further on its 10,000-year orbit. It sits in a part of the solar system that some astronomers had thought empty. It is redder and brighter than anything astronomers have seen in the outer solar system, and scientists don't know why.
. . Pluto is about 2,274 km wide. Sedna is estimated at no more than 1,770 km in diameter. It may be the largest object in the solar system after Pluto, but more observations are needed to pin that down.
. . "If you were stand on the surface of Sedna today and you held a pin at arms length, you could cover the entire Sun with the head of that pin", Brown said.
. . Last month, the team announced 2004 DW, which was estimated to be between 840 to 1,880 km wide. The best estimate is that 2004 DW is 1,600 km across. It is nearly 47 AU from the Sun.
. . In 2002, the group found 2002 LM60, also named Quaoar (KWAH-o-ar). It is roughly 1,250 km wide, about half as big as Pluto. Quaoar is 42 AU from the Sun.
. . "If Pluto were discovered after all these discoveries, would we have called it a planet? No", said Chiang, an astronomer at the University of California at Berkeley. Brown said Sedna occupies a region of space beyond the Kuiper Belt but inside the theorized Oort Cloud.
. . Brown said the discovery suggests the Oort Cloud might be more dense --containing more objects-- than was previously thought. "It is very likely that there are more inner Oort cloud objects like Sedna", Brown says, noting that only 15% of the sky has been surveyed for objects so dim as this.
. . Sedna probably was formed nearer to the Sun, in what's now the Kuiper Belt. Like other objects there, it would have been gravitationally booted outward by the giant planets early in the 4.6-billion-year history of the solar system. Many such objects should have been ejected from the solar system. But interactions with very distant stars could have forced some to remain in the Oort Cloud.
. . Sedna might turn out to be a Kuiper Belt Object that has been scattered outward. The problem, he said, is that scientists don't know enough about either region to say for sure what belongs where and what is or isn't in between. Stern said it is not even clear whether there is actually a gap between the two regions.
. . Sedna was found using the 48-inch Samuel Oschin Telescope at Caltech's Palomar Observatory near San Diego. The discovery was confirmed with other observatories, and the object's size was pinned down using NASA's new Spitzer Space Telescope.

Mar 11, 04: Rosetta, launched on March 2, will come within about 1,700 kilometers of a small space rock called Steins, measuring just 3-4 km across, on September 5, 2008. It will pass within about 3,000 kms of asteroid Lutetia, a far bigger object measuring around 100 kms across, in a second flyby on July 10, 2010.
. . "Rosetta will obtain spectacular images as it flies by these primorial rocks." "Its onboard instruments will provide information on the mass and density of the asteroids, thus telling us more about their composition, and will also measure their subsurface temperature and look for gas and dust around them."
. . Rosetta is scheduled to rendezvous with Comet Churyumov-Gerasimenko in 2014. The orbiter will also send down a small lander to its surface to test soil samples.
Mar 10, 04: Uranus --and Neptune, too, Voyager found-- is radically different. Their magnetic fields are tipped over (the north-to-south line lies midway to the equator or even closer) and there are two north and two south poles, as if the field were produced by two bar magnets. The reason for this, according to a new theory: The underlying structures of Uranus and Neptune are radically different from what was previously assumed about these cold, distant planets, and is different from those of Jupiter and Saturn. It suggests that these two outer planets may have only a thin layer of metallic convecting fluid.
. . This has a big effect on the magnetic field, limiting it to a thin "shell" just under the gassy hydrogen surface. That phenomenon may also cause the field to be tipped on its side compared to the rotational axis and also inflict the "quadrupole" effect.
Mar 9, 04: Astronomers have gotten a good look at X-rays from the ringed planet Saturn, and they're puzzled by the results that defy current theory.
. . The image, made with NASA's Chandra X-ray Observatory, shows the X-rays are concentrated near Saturn's equator. X-rays from Jupiter, however, are concentrated mostly near the poles.
. . "This indicates that Saturn's X-ray emission is due to the scattering of solar X-rays by Saturn's atmosphere", said Jan-Uwe Ness, of the University of Hamburg in Germany. "It's a puzzle, since the intensity of Saturn's X-rays requires that Saturn reflects X-rays fifty times more efficiently than the Moon."
. . The observed 90 megawatts of X-ray power from Saturn's equatorial region is roughly consistent with previous observations of the X-radiation from Jupiter's equatorial region. This suggests that both giant, gaseous planets reflect solar X-rays at unexpectedly high rates.
Mar 3, 04: One notion --conceived by NASA's John Mankins, a human and robotic technology specialist-- is a Habitat Robot, also dubbed "Habot" for short.
. . Habot is a radical departure from lunar base studies, Cohen noted. Habot modules would land on six movable legs, making use of those legs to strut their stuff robotically away from a lunar landing zone. "With self- ambulating lunar base modules, it would be feasible to have each module separate itself from its retro-rocket thruster unit, and walk [KMs] away from the landing zone to a pre- selected site. These walking modules can operate in an autonomous or teleoperated mode to navigate the lunar surface."
. . On arrival at a predetermined site on Luna, the six-legged walking modules can bond. That is, they combine and make pressure-port connections among themselves. The result: a multi-module pressurized lunar base. Moon-landing astronauts would find a ready-and-waiting base. Once the lunar explorers depart the scene, the Habots separate from each other to begin their walk elsewhere. It is also possible for crew members to go along for the ride.

. . But before any lunar outpost dots the Moon, there's survey work to do. Already swinging into high gear is NASA's Goddard Space Flight Center in Greenbelt, Maryland. Scientists and engineers there have begun scoping out a Lunar Reconnaissance Orbiter to be launched in 2008. There's a need for a focused look at Luna's south and north polar regions to clarify the nature and extent of lunar hydrogen deposits, both ice and implanted solar-wind hydrogen.
. . LunaCorp is eager to offer SuperSat, a Moon probe that can be assembled on the International Space Station. After fabrication on orbit, it would then be sent into orbit around Luna. SuperSat could provide broadband communications from Luna, enhanced with sponsorship and television funding.
. . SuperSat is intended to deliver the first high- resolution digital video of a voyage from the Earth to Luna, and create the first digital map of the lunar surface -- looking for non-dangerous landing spots near Luna's poles for upcoming rover missions.
. . Europe' SMART-1 is on its way. Japan is readying lunar missions for 2004 and 2005. India and China are also preparing to send a series of robotic missions to Luna.
. . "Domes will be able to be even larger due to the support from the internal air pressure. This will enable the realization of humans' eons-long dream of flying like birds.
. . "The road to lunar development will be open and it will not close a second time."

Feb 25, 04: In California, authorities in defending the Earth from a collision with an asteroid or comet have gathered to detail ways to thwart future impacts and deal with the calamity if our planet is struck. An international group of scientists, engineers, space policy makers, and others are taking on the task of improving our ability to successfully defend our planet from possible impact threats. The meeting will recur every four years.
. . If a planetisimal 100 yards or more across were to strike the Pacific Ocean, it would generate a tsunami capable of destroying the major cities of the US West Coast.
. . Slowing a 'tisimal down by even a few inches a second could change its trajectory enough to prevent its ever crossing paths with the Earth. The Earth moves in space the equivalent of its own diameter in just six minutes. So to move an Earth-bound asteroid off target, it would be enough to delay its arrival time by six minutes, allowing it to harmlessly sweep past.
Feb 19, 04: A newfound hunk of ice and rock beyond Neptune is larger than most and might contend for the title of the biggest object in the solar system besides the Sun, planets, moons and Pluto. It's the 15th object larger than 500 km in diameter found in the region.
. . The object is in a region of frozen, comet-like bodies called the Kuiper Belt. Preliminary observations suggest the icy rock, labeled 2004-DW, is somewhere between 840 & 1,880 km wide. Physics dictates that objects this large be generally round, like mini-worlds. It orbits the Sun every 252-288 years, mostly beyond Pluto's orbit. Preliminary measurements suggest the object follows an elliptical orbit that takes it as close as 4.3 billion km to the sun and as far out as 7.5 billion km.
. . Other than Pluto, the largest known Kuiper Belt Object, or KBO, is called Quaoar (KWAH-o-ar) and was discovered in 2002. Quaoar is roughly 1,250 km wide, about half as wide as Pluto.
Feb 19, 04: Europe is to launch the first space mission to attempt to land on the nucleus of a comet. The Rosetta spacecraft and lander will blast off Feb 26th from the Kourou launch site in French Guiana. Its original launch date a year ago was canceled after an explosion on take-off.
. . No existing rocket is powerful enough to send the spacecraft directly to its destination, comet 67P/Churyumov- Gerasimenko. Rosetta will swing round Mars and the Earth several times, picking up momentum like a sling-shot before breaking free and hurtling off. It will take 10 years just to reach its target.
. . In 2014, the spacecraft will enter the comet's orbit, brake and eventually drop a lander on to its nucleus. It will take images of the comet and samples of its surface. Nothing is known about the surface of the nucleus, which has a diameter roughly the length of a long runway. "The lander was designed to deal with different surfaces --at one extreme, a surface like concrete, at the other, like candyfloss."
. . Wright said it was possible that the water on earth, essential to the beginning of life, was originally brought by comets --a connection Rosetta could shed light on. It could also help investigations into the threat rogue "asteroids" pose to Earth.
Feb 17, 04: Russian engineers have begun design work on a new spacecraft that would be twice as big and spacious as the existing Soyuz crew capsules. The new craft will be able to carry at least six cosmonauts and have a reusable crew section. will have a takeoff weight of 12-14 metric tons --about twice as much as the Soyuz. Energiya has also proposed developing a new booster rocket.
Feb 12, 04: At around 10 o'clock Mars-time on a recent morning, pockets of cooler and warmer air varying by as much as 4 degrees C drifted past the rover.
Feb 11, 04: The Mars Science Laboratory is an all-terrain, all-purpose machine, akin to an extraterrestrial Sport Utility Vehicle to be rocketed toward Mars in 2009. MSL is designed to operate a full martian year, or two Earth years. It would make the first wheels-down landing on the planet. No need for airbags, nor lengthy preparations to get rolling off an air-bagged shell. This Mars vehicle is lowered onto the surface via a Skycrane.
. . After diving through the martian atmosphere, and then under a parachute, the Skycrane/MSL hardware would then be set free. A suite of controllable engines first run hot and heavy to slow the structure down. By reducing thrust, the Skycrane eases down, & enters hover mode for a nominal five seconds. It hangs in mid-air a mere 5 meters above a pre-determined spot. The MSL slips down a tether to reach Mars. MSL's touchdown speed would be modest: one meter per second. "That's like falling from three inches on Earth." Its depositing duty complete, the Skycrane departs the scene for a crash landing distant from the rover's arrival area.
. . The six-wheel mobile lab is five times larger than the current wheeled robot design --that class of rover is around 180 kg (400#). The heftier MSL could tip the scale at 900 kg (1,980#) --10 times the payload of a Spirit/Opportunity-class rover.
. . Boeing is working on competing nuclear battery designs for the laboratory. It adds up to a billion dollar plus probe.
Feb 9, 04: JIMO --the Jupiter Icy Moons Orbiter-- has the potential to be the biggest and most expensive spacecraft NASA has ever built. Although NASA has yet to set firm requirements for JIMO --or make public a cost estimate-- agency officials are generally looking at a spacecraft built to operate 10-15 years.
. . The mighty spacecraft NASA envisions would be powered by a nuclear fission reactor -- essentially plutonium-powered-- capable of pumping out 100 kilowatts of power. The reactor would power JIMO's propulsion system and provide more electricity than any spacecraft has ever had for instruments, computers and communications.
. . Mills said the spacecraft could easily be 50 meters long when fully deployed -- about half the size of the international space station. Boeing, at least, is concentrating on designing a spacecraft light enough to launch in one piece aboard a heavy lift version of either the Delta 4 or Atlas 5 rockets.
. . JIMO will be just the first in a long line of nuclear-powered spacecraft ordered by NASA for solar system exploration. Aside from the enhanced mobility promised by nuclear propulsion --JIMO is being designed to visit three of Jupiter's moons during its mission-- nuclear spacecraft are expected to be anything but power constrained.
Feb 4, 04: European Space Agency (ESA) is gearing up for Rosetta. Set for a Feb. 26 launch, with two potential windows spaced 20 minutes apart, Rosetta should finally begin its trek to Comet 67P/Churyumov-Gerasimenko, a ball of ice, dirt and dust that sweeps through the Solar System almost every six years or so. The mission is twofold, consisting of an orbiter expected to circle the comet upon arrival and a small lander to touchdown shortly thereafter.
. . A setback kept Rosetta from visiting its initial target, the Comet Wirtanen. Mission planners were able to find a suitable replacement: Churyumov-Gerasimenko --four Km wide.
. . But the two spacecraft still have a 10-year journey before reaching their destination. If all goes as planned, the mission should meet Comet Churyumov- Gerasimenko in 2014. Rosetta has to swing by Earth not once but three times. A Mars flyby in 2007 is also required to fling the spacecraft through the asteroid belt.
. . Rosetta has 21 scientific instruments --11 on the orbiter and 10 on the lander. There are cameras to take high-resolution images of the comet's surface and shape, various spectrophotometers to study its chemical composition, as well as instruments to measure the gases and dust. The mission runs about two years, following the comet until it reaches its closest point to the Sun. Mission controllers plan to awaken the spacecraft briefly in 2008 during its pass through the asteroid belt to study nearby space rocks, though definite targets won't be announced until later.
. . The lander doesn't use a rocket engine to control the descent, just a small reaction control system, so its survival depends on the orbiter matching the relative speed of the comet, allowing it to trace a slow, ballistic trajectory to the surface. Three landing struts are designed to absorb any impact shock, and can lift or tilt the lander to keep it in an upright position. It should hit the comet surface at a speed of about one meter per second. "We have harpoons that will anchor the lander to the comet."
. . Data from the lander can only reach Earth after being relayed through the orbiter.
Jan 30, 04: Bush announced that the shuttle program would be retired in 2010, and replaced by a far more ambitious program. Beginning next fall, NASA plans to resume a full program of shuttle launches to finish the construction of the orbiting International Space Station. To accomplish that, the remaining shuttles --Atlantis, Discovery and Endeavor-- will often be in orbit simultaneously, with a total of five missions per year before they are consigned to a museum.
Jan 26, 04: Scientists have long theorized about a population of small, asteroid-like objects roaming around the Sun inside the orbit of Mercury. None has been found. A region of space inside Mercury's orbit is gravitationally stable in such a way, theorists say, that space rocks could survive there. All similarly stable areas of the solar system do contain objects.
. . So far, the lack of any discoveries has only served to put loose constraints on the size and quantity of possible Vulcanoids. Any that remain are probably not more than about 60 km (37 miles) in diameter.
. . The rocket-mounted VULCAM, as the 3-pound instrument is called, is the most far-reaching effort yet.
. . The X-Prize winner will have the needed capability.
Jan 15, 04: Bookmakers William Hill said they were offering 50/1 odds against a man walking on Mars by December 31, 2030. Bush announced plans to send humans back to the moon as early as 2015 and eventually to Mars. The bookies are also sceptical that humans will soon return to the moon --they are taking bets at 10/1 against anyone reaching the moon before December 31, 2015.
Jan 14, 04: Robert Park, a physicist at the University of Maryland and director of the Washington office of the American Physical Society, does not think Bush's plan makes scientific sense. "We've got a geologist on Mars right now and he's doing a great job", Park said. "If we put a human there, he's locked in a spacesuit, he has no sense of touch. There's not much to hear on Mars. All he's really got is a sense of sight. And the eyes we've got on Mars right now are better than any human eyes. We don't stick our finger into a liquid to see what the temperature is, we put a thermometer."
Jan 6, 04: Telemetry data gathered during Stardust's 12- minute flight through a storm of cometary particles traveling at six times the speed of a bullet indicated that the spacecraft encountered several high-speed jets of particles rather than a cloud of evenly distributed dust. It flew just 149 miles from Wild 2's nucleus.
. . Particles from the comet were trapped in a porous, sponge-like substance called aerogel in the collector mechanism's grid. The grid will return to Earth in 2006 inside a capsule and will be opened in a clean room to prevent contamination.
. . The first images sent back from Stardust showed five gas columns that appeared to emanate from deep pits in Wild 2's deeply pockmarked surface. The pits themselves could be impact craters or sinkholes created by sublimation, when sunlight converts the comet's nucleus to gas. The pits discharge gas and dust at supersonic speed when exposed to the sun but go dormant when dark. "Not only did we image jets of material spewing out from the comet but for the first time in history we can actually see the location of their origin on the surface of the comet."
. . The photos of the comet's five-km (3.1- mile) wide nucleus also showed an unexpected variety of formations --from craters to flat-bottomed depressions lined by sheer cliffs to mountains-- that scientists will study to learn how comets are formed.
Jan 5, 04: The Iranian Defense Minister said Iran would launch a locally made satellite within 18 months. No details on the type of satellite Iran planned to launch were given. "Iran will be the first Islamic country to go into space with a locally produced satellite and launch pad system."
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