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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion - only available here! Current mission news: MGS (latest pictures!) + Cassini + Stardust |
if the detection rate - by volunteers around the world - continues at the present pace: NASA and ESA Releases. 10 years ago Hale-Bopp was discovered: Alamogordo News. Perseids previews for 2005: Science@NASA, SC. No Leonids outburst this year: a Russian paper.
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Kuiper Belt Object larger than Pluto found!This had to happen one day: Astronomers scanning the sky with the 1.2 meter Oshin Schmidt camera on Palomar Mtn. have stumbled upon a member of the Kuiper Belt that is larger than the planet(?) Pluto. By how much they can not say yet, unfortunately, because the albedo of 2003UB313 is unknown, but even at 100% reflectivity the object (currently at its 97 AU aphelion from the Sun but a regular member of the Belt with a perihelion distance of 36 AU) would outsize Pluto. An upper limit for the diameter of 3000 km has been set by the nondetection with the Spitzer Space Telescope, so the most likely diameter may be 1.5 times Pluto. As the number indicates, the object was detected first in 2003, but only this year did it dawn on the discoverers what they had hit on. (Incidentally two more very big Kuiperoids have been announced almost simultaneously, though none of them exceeds Pluto in size.) Now the debate on whether Pluto is a planet - or what a planet is at all - will resume in full swing ... |
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Evidence for watery volcanism on Saturn's moon Enceladushas been found by the Cassini spacecraft during a particularly close flyby (apprioaching the surface to 175 km) on July 14: The spacecraft sensed a huge cloud of water vapor over the moon's south pole, and warm fractures where evaporating ice probably supplies the vapor cloud. Cassini has also confirmed Enceladus is the major source of Saturn's largest ring, the E-ring. "Enceladus is the smallest body so far found that seems to have active volcanism," said Dr. Torrence Johnson, Cassini imaging-team member at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Enceladus' localized water vapor atmosphere is reminiscent of comets. 'Warm spots' in its icy and cracked surface are probably the result of heat from tidal energy like the volcanoes on Jupiter's moon Io. And its geologically young surface of water ice, softened by heat from below, resembles areas on Jupiter's moons, Europa and Ganymede."Cassini flew within 175 kilometers of Enceladus on July 14: Data collected during that flyby confirm an extended and dynamic atmosphere. This atmosphere was first detected by the magnetometer during a distant flyby earlier this year. The ion and neutral mass spectrometer and the ultraviolet imaging spectrograph found the atmosphere contains water vapor. The mass spectrometer found the water vapor comprises about 65 percent of the atmosphere, with molecular hydrogen at about 20 percent. The rest is mostly carbon dioxide and some combination of molecular nitrogen and carbon monoxide. The variation of water vapor density with altitude suggests the water vapor may come from a localized source comparable to a geothermal hot spot. The ultraviolet results strongly suggest a local vapor cloud. The fact that the atmosphere persists on this low-gravity world, instead of instantly escaping into space, suggests the moon is geologically active enough to replenish the water vapor at a slow, continuous rate. |
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Discovery in fine shape for returnIntense scrutiny of orbiter finds no significant damage / Mission extended one day / Repair techniques tested during 1st EVAThree times the exterior of the orbiter Discovery has been scrutinzed, on July 27, 28 and 29, with cameras and sensors on a robot arm and with telephoto lenses from the ISS: No damage of any concern was found. Discovery's protective tiles and thermal blankets have already passed review and are cleared for entry, while analysis continues on the reinforced carbon-carbon areas and two protruding gap fillers. A day in orbit has been added to the crew's schedule after the third spacewalk, so that more work can be done on the ISS; landing is now planned for Aug. 8. The first EVA of mission STS-114 was a success on July 30, with various work on the outside of the ISS and tests of two future repair techniques for damage to the orbiter's skin (using dummy components, not the real orbiter, of course).Assessments for the future of the whole shuttle program meanwhile range from calls to stop all flights for good to the optimistic view expressed by the NASA Administrator that the next shuttle will fly even this year. Meanwhile transfers of water and supplies to the International Space Station continue: Two additional collapsible water containers holding more than 10 gallons each are expected to be added to the cargo transfer list before the Shuttle leaves, bringing to 17 the number that will be left behind, a substantial increase in the amount of available water. ISS Program Manager Bill Gerstenmaier said in a news conference on July 30 that the program was very happy to have the additional supplies and that the station's consumables status had improved considerably with Discovery's visit. Discovery launched & docked to ISS - but the shuttles are grounded, againThe orbiter itself has apparently not suffered significant damage / But big piece of ET foam fell off in plain sight of tank cam / It missed the orbiter by a wide margin but it could have damaged it under other circumstancesThis is not how NASA had wanted the Return to Flight of the space shuttle fleet to happen: First a bizarre - but entirely harmless - incident with a window cover falling off and damaging orbiter tiles on the pad, then the unexpected return of the "unexplained anomaly" with an Engine Cut-Off sensor in the hydrogen tank that caused a 2-week launch delay, and when the shuttle finally took off on July 26, another major debris event occured at the External Tank! When NASA managers held their first post-lauch news conference 80 minutes afterwards they apparently had not noticed the incident - but several TV reporters had and raised questions about it (the crucial moment was only seen during later replays of the launch from numerous camera angles; when it happened, the world feed from NASA Select TV showed a different view). Who could have known that 30 hours later that very incident would ground the shuttles, again and indefinitely?The severity of the incident had become clear when detailled still images of the just jettisoned ET were downlinked to Earth: "Initial analysis of the imagery shows a large piece of foam that separated from the tank during the Shuttle's ascent to orbit. The foam detached from an area of the tank called the Protuberance Air Load (PAL) Ramp" - and at a different ascent phase air currents could have make it impact the orbiter, potentially causing Columbia-like damage: Another redesign of the tank isolation is thus unavoidable, and that can take (many?) months! "Until we're ready, we won't go fly again," said a visibly shocked shuttle program manager Bill Parsons at a news conference late on July 27: "I don't know when that might be, I'll state that up front. We're just in the beginning of this process of understanding. This is a test flight. This is a flight we had to go off and try to get as much information as we could and see if the changes that we had made to the tank were sufficient. Obviously, we have some more work to do." On July 28 NASA engineers were busily evaluating the loss of the large piece of insulation foam from Discovery's external fuel tank: Based on initial assessments, the foam - which appears to measure approximately 60 to 80 cm long, 25 to 30 cm wide and 6 to 20 cm thick - was seen by high-resolution camera equipment added to the Shuttle system after the loss of Columbia in 2003. There was no indication the piece of foam caused any damage to Discovery. The Shuttle will undergo further inspection beginning Thursday to check for any significant damage to the orbiter. "As with any unexpected occurrence, we will closely and thoroughly evaluate this event and make any needed modifications to the Shuttle before we launch again," NASA Administrator Michael Griffin said: "This is a test flight. Among the things we are testing are the integrity of the foam insulation and the performance of new camera equipment installed to detect problems. The cameras worked well. The foam did not." Discovery's mission, in contrast, is progressing smoothly: The docking to the ISS took place right on time on July 28. |
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Deep Impact changes trajectory, heads back to Earth for possible 2nd missionOn July 20 NASA's Deep Impact flyby spacecraft executed its sixth trajectory correction maneuver: It placed the spacecraft on a trajectory to fly past Earth in late December 2007. The maneuver allows NASA to preserve options for future use of the spacecraft. "This maneuver will keep the spacecraft in the vicinity of the inner planets, thereby making the task of tracking and communicating with it easier," said NASA's Director of Solar System Division, Science Mission Directorate, Andy Dantzler. He also announced that all investigators interested in using the Deep Impact Flyby Spacecraft for further science investigations must submit proposals to the 2005 Discovery Program Announcement of Opportunity for a Mission of Opportunity - something that has never happened before (with other deep space missions outliving their original mission, NASA just kept paying the bill, guided mainly by less formal review procedures)."All proposals for use of the Deep Impact spacecraft will be evaluated for science merit and feasibility along with all submitted proposal for Missions of Opportunity," Dantzler said: "The spacecraft is being offered as is. Proposers must include mission management and spacecraft operations in the total proposed funding." Such an extended mission would cost approximately 30 million U.S.$, according to AW&ST of July 11 - less than 10% of the cost of the original mission! All systems onboard are in perfect shape despite the terrifying flight through the dusty coma of Tempel 1, and the cameras and especially the capable IR spectrometer could do fine science in a flyby of another comet nucleus. Boethin, which could be reached in late 2008, would be the best target - it would be another comet discoverd by a German amateur astronomer. Given that no lauch would be required anymore and a healthy spacecraft is basically enroute to it, there is simply no argument not to do this extended mission. Meanwhile more scientific findings from the July 4 impact and its aftermath have been published - in a rather uncoordinated fashion by many of the various institutes involved, and sometimes the reports seem to contradict each other. But generally it seems clear that the impact freed (or produced) a lot of very fine dust (that caused the extremely bright initial ejecta plume) and comparably little gas, though many interesting spectral features have been indentified in the latter. It is far from clear, though, whether anything really pristine has been dug up in the depth of the nucleus. The impact has failed to cause any longlived enhanced activity of the nucleus, and less than 10 days after the impact the coma looked like just before, as if nothing had happened. Ah, and all those who bet money on the size of the impact crater? They are still waiting for any official word: The dust ejecta completely blocked the view, and one can only extrapolate from the shape of their plume that the crater must measure 100 to 300 meters. |
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First 25 dishes ordered for giant radio interferometer ALMAOn July 13 the American side of the joint U.S.-European ALMA project has ordered 25 12-meter dishes from the (originally German but now U.S.-owned) company VertexRSI which has thus won out over a competitor, the Cosmic Mirror has learned. The European side, represented by the European Southern Observatory, will soon order another 25 such dishes (when the ESO Council has released the funds), in all likelyhood from the same manufacturer: This will bring the total to 50, 14 short of the original goal of 64 dishes. Steep rises in the price of steel in recent years would have made the original interferometer too expensive, and 50 is the minimum number of dishes required by the astronomers for good interferometric 2D images and collecting power alike. While there are some fears that the total number of ALMA dishes may end up short of even 50, on the other hand at least the Americans have retained the option to order another 7 antennae from Vertex. |
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Three discoveries from the varied world of circumstellar diskshave been reported in rapid succession: There is a new case of an edge-on disk around an A star as revealed by Hubble's NICMOS IR camera/coronagraph, there is the by far oldest disk around a star which at 25 million years apparently still hasn't gotten around to making planets - and there is a particularly dust-rich disk around a star that contains about 1 million times as much dust as there is in the solar system today. The most likely explanation is a recent - i.e. in the past 1000 years - collision between two major planetary bodies in the system.The first planet of a triple star systemhas been detected: It is circling one of the stars in a very tight orbit every 3.4 days while the other two stars have a distance comparable to that of Saturn from the Sun. (Actually they form a close binary system of their own which is orbiting the primary star on an elongated ellipse with the distance varying between 6 and 18 Astronomical Units.) At times, thus, there will be three 'Suns' in that planet's sky, a yellow one (its own), an orange and at red one. The mystery is now how this planet could have formed in the first place: It is generally assumed that such 'hot Jupiters' condense at about 3 AU from their parent star and later migrate inwards by exchange of angular momentum. The other other stars in this system however, should have trunctated the protoplanetary disk to a radius of just 1.3 AU, so the 'standard' way of forming the planet could not have worked. |
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Japanese X-ray satellite launched, replaces spacecraft lost in 2000On July 10 an M-V vehicle successfully launched Japan's Astro E-2 which has since been renamed Suzaku: This X-ray astronomy satellite replaces an identical spacecraft lost in a launch accident with the same carrier in the year 2000 (see Updates # 172, story 4, and 174, story 2). Suzaku carries three different instruments, the primary one being the high-resolution X-ray Spectrometer (XRS), developed jointly by NASA and ISAS: The XRS measures the heat created by the individual X-ray photons it collects. To sense the heat of a single photon, the XRS detector must be cooled to an extremely low temperature, only 0.06 Kelvin: This will make the XRS much colder than space. Using this new technique, scientists can measure higher X-ray energies with a precision about ten times greater than with previous sensors.Astro-E2 was developed at ISAS in collaboration with U.S. scientists and other Japanese institutions. The mission will contain three X-ray instruments. Scientists will use these to study phenomena that radiate predominantly in X- rays. Astro-E2 will study black holes and the creation of chemical elements necessary for life. Key targets include hot gas falling toward black holes; the million-degree ejecta of star explosions filled with newly minted elements such as oxygen and calcium; and the optically invisible gas between stars and galaxies, which comprise most of the ordinary mass in the universe. Along with the XRS are four X-ray Imaging Spectrometer (XIS) instruments, a collaboration among Japanese institutions and MIT, and the Hard X- Ray Detector (HXD), built by the University of Tokyo, ISAS and other Japanese institutions. |
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Mars UpdateMore MER papers have been published. MPG and Cornell Press Releases, Mars Rover Journal entry of July 21, pictures/movies + 7216 and (of dust devils) # PIA071... 40, 39 and 38, Science@NASA of July 14 and coverage of July 28: Plan. Soc. July 20: SC. July 19: Telegr. July 6: NwS, SC. Mars Express releases of July 28 [SR] and July 15 and coverage of July 29: BBC, NwS, TP. July 28: Plan. Soc. July 27: NwS. July 25: TP. July 20: APOD. Beagle 2 chief has MS: BBC. Mars Methane: AB (earlier, still earlier). Forward contamination risk? Nat'l Acad. PR, NG. MGS pictures # PIA041... 03 02 and 01 and PIA039... 87. Odyssey picture # PIA041... 08.Meteorites tell story for cold, dry Mars for most of its history: Caltech [SR] and MIT Press Releases, PSRD, BBC, NwS, Reg., SC, Rtr, ST, BdW. Nonsensical Mars chain letter still making the rounds: Science@NASA, Huntsv. Times. Germany to join Aurora program: ESA Release, Reg., Mars Soc. MRO launch approaching: NASA Release, Plan. Soc., NwS, and SciAm stories & launch prep pix 35... 25, 24, 23, 22. Mars Telecom orbiter cancelled: RMN, AD, NwS, ST. |
Stellar occultation by Charon observedAstronomers recently succeeded in observing distant Pluto's tiny moon, Charon, hide a star - such an event had been seen only once before: MIT Release, Plan. Soc., BBC, SC.Arizona's Meteor Crater is now money pit - it has over 300,000 paying visitors every year: Durango Herald. New meteorite find in Manitoba: SD. Giant prominence erupts on Sun on July 16: EIT movie. Loop prominence seen widely on July 13 and 14: Gährken, Murner, Legault, Favre, Hartlap, Dalouzy, Vandebergh and Palmer pictures. Solar forcing no big climate factor: RealClimate. A supernova that won't fade awaySN 1979C is still the brightest X-ray source in its galaxy: ESA Release, NwS. Amateur group finds 100 SNe: S&T.Progenitor of supernova in Messier 51 tracked down in old HST image: HST and Berkeley Releases, S&T. Groundbased observations: NOAO Press Release, APOD, S&T, The Leaf Chronicle and July 4 and July 6 pictures. Supernovae give off blasts of cosmic rays that bombard the Earth and change its surface rocks - the CRONUS (cosmic-ray produced nuclide systematics) initiative will use that for dating them: NSF PR. LMXB/msec-PSR link strengthenedby an X-ray millisecond pulsar with a characteristic spectrum: Chandra Press Release.Iron spectra from massive Black Holes have been observed by Chandra in some 300 galaxies: Press Release. Two BH's in one normal spiral galaxy? NwS. Silhouette reveals hidden shape of young star's envelope in the Omega Nebula (M17): NAOJ Press Release, SC. SMA observes jet in HH 211: CfA Release. IMF of the Trapezium: Gemini PR. Well-hidden neutron star unveiled with three different space observatories: ESA Release. High-energy gamma rays from a microquasar: PPARC, MPG and RUB Press Releases. |
Mirror for biggest telescope in the makingAstronomers have begun casting the first of seven giant light-collecting mirrors that will ultimately comprise a telescope four-and-a-half times larger than any other optical scope: Dsc.Fire threatened Arizona observatory - a wildfire in the Arizona mountains approached to within 1.6 km of the Fred Whipple Observatory on Mt. Hopkins, but it is now out: CfA (earlier) and U of A Press Releases, NwS, ST. SDSS II will come, extending the Sloan Digital Sky Survey until 2008: Press Release. A Dobsonian in space?!The design of an unfolding space telescope - based on ideas from amateur astronomy - has already progressed to µg testing in parabolic flights: ESA Release.Ground-breaking for the Discovery Channel Telescope in Arizona has taken place: Lowell Press Release, SC. Major study about Extremely Large Telescopes gets underway in Europe: PPARC Press Release. Cluster spacecraft reach greatest separationThis operation, marking the fifth anniversary of Cluster in space, transforms Cluster in the first 'multi-scale' mission ever: ESA Release.Spiral arms in NGC 4615 revealed by GALEX' UV vision: JPL Release, PhotoJournal, NwS. Did Chandra solve a problem with our Sun?The models for its convection zone don't work well - they would if the discovery of much more neon than expected in 21 neighboring Sun-like stars extend to Sol as well: Chandra Press Release.GRB in Integral's optical camera f.o.v. - on June 26 it happened for the 1st time: ESA Release. Still no clarity over Cosmos 1 mishapThe Americans couldn't get as involved in launch matters as they would have liked - and there could be another attempt in 2006: July 20 Update, AD, SN, ST.Tracking spacecraft from Australia - key moments remembered: Australian. |
All other historical issues can be found in the Archive.
Compiled and written by Daniel Fischer