Astronomy - March 23 1999

Catastrophes that happen on a global scale are by definition extraterrestrial. For many centuries astronomers and other stargazers have searched the skies for new discoveries to understand life on Earth within the framework of their times. For over three centuries the heavens have been remotely explored using telescopes, and this has resulted in many changes. Aristotle's ideas that the stars are lights fixed in a huge sphere orbiting the Earth, or that stones can't fall from the skies, have been discarded, although it should be noted that recent large impacts on the Earth were barely acknowledged until 1960. There may be some folks who don't realize that the Earth gets bombarded all day long, every day. Dr. Louis A. Frank discovered that Earth's upper atmosphere receives a steady stream of small iceballs about the size of a small house, which are destroyed at 600 to 15,000 miles altitude.
Some people that I know (or have written on the Usenet and to letters to various periodicals) insist that the Earth's atmosphere would make everything burn up, no matter how large. In fact, Earth's gravity could accelerate one of the hundreds of thousands of nearby objects in a similar orbital path to a velocity of ten or twenty miles per second during the hour or so prior to impact. There would be no warning. Even an object a mile across would create a disaster worse than any other type of event.
Some scientists have spoken of the odds of a large impact in a human lifetime. These figures are not reliable. The actual number of objects is not known and the number of recent large impacts is obscure. Large objects entering the atmosphere would have mostly gone undetected until missile defense and other radar systems were installed beginning after WWII. Estimates of the number and size of unknown objects are based on the number of known craters on Earth, and are diminished by the assumption that the number of objects was much higher near the beginning of the solar system and has been reduced by impacts and not increased by any unusual events. The long term stability of orbits is another assumption in these estimates. Asteroid Cruithne 3753, a mere 5 kilometers across, is in a 20 degree inclination and 0.51 eccentricity, in a horseshoe orbit.
Before large impacts were considered possible in recent times, features like Meteor Crater were considered to be volcanic in origin despite the lack of any volcanic features other than the crater itself. Besides the Tunguska event, there is evidence for somewhat smaller impacts in the Amazon , in the southern Indian Ocean in 1978, Saudi Arabia, and a very recent event in Greenland. Only one of these impacts has been thoroughly substantiated, but all three took place during the 20th century.
Furthermore, if plate tectonics is valid (that's the consensus), most impact craters, even the largest, would have been recycled into the mantle or subsided beneath the seas, and erosion would obscure the remainder. Add that to the fact that barely any effort is underway to identify craters on Earth, and you have a handle on how reliable odds calculations could be right now.
More importantly, estimates are not the same as observed sightings. The biggest problem with the calculations is that the actual number of Near Earth Objects is unknown, and the researchers looking for them don't have the facilities to look any faster. Estimates as to the number that will be found are not reliable for some of the reasons noted in the previous paragraphs, namely, that the true number of past impacts on Earth is basically unknown. Smaller events like Tunguska could destroy any of the largest cities on Earth, but in a few centuries there would be little if any trace of such an event, other than the human accounts. If the past is any indicator, human testimony would be held in very low regard.
Another possible factor in their detection and estimation of their quantity is the assumption that all the objects are primordial and were not formed in a relatively short time in a few unique events, such as exploding planets (see Van Flandern below) or collisions between relatively large bodies, or breaking up in the gravitational influence of a planet. In other words, there may not be a uniform distribution of such bodies in bands like the asteroid belt between Mars and Jupiter.
Although you and I may be the only ones who will ever read these words, consider this a call for more efforts and money to be spent in this survey. Radar surveys, perhaps conducted from orbit, seem like a good way to get a handle on the true number of these objects. Radar data on a possible NEO could be used to trigger an optical search, thus saving time and increasing the number of objects found. The greatest threat are those smallish companions on Earth's journey, some of which are at least as large as the K-T event asteroid. Cumulative forces, or a sudden nudge from a non-threatening object like a comet or asteroid, could pull down a mile wide planet killer. Despite possible eons spent in the vicinity of the Earth, such an object would come down without ever having been previously catalogued.
"On September 29, 2004, Toutatis will pass by Earth at a range of four times the distance between the Earth and the Moon, the closest approach of any known asteroid or comet between now and 2060. One consequence of the asteroid's frequent close approaches to Earth is that its trajectory more than several centuries from now cannot be predicted accurately. In fact, of all the Earth-crossing asteroids, the orbit of Toutatis is thought to be one of the most chaotic." [ found in web search, forgot to save the URL ]
See the new Catastrophism section in the Bookshop.
See the new Miscellaneous section in the Bookshop for additional science titles.
Asteroids - Deadly Impact is a National Geographic video from 1997. I purchased a copy at Sam's Club for $12.99, but it should be available at this link or anywhere in North America where videos are sold (also available as one of three videos in Nature Strikes; unfortunately, neither is available outside the US and Canada). I've always been a sucker for the theme music of NG specials, and grew up on them. This one is particularly well done.
The star, if you will, is the late Eugene Shoemaker. It was largely due to his efforts that continual impacts have become an acceptable topic. If it were not for Shoemaker, it is likely that the K-T boundary extinctions would remain poorly understood and essentially unexplained. If it were not for the efforts of Eugene and Carolyn Shoemaker and David Levy using a small, obsolete telescope to hunt for comets, it is likely that the large cometary impact on the planet Jupiter would never have been observed. That observation captured the public imagination all over the world and strengthened scientists' interests in catastrophism, particularly celestial catastrophism.
It is weird to think about the fact that, as recently as 1963, what we now recognize as Meteor Crater in Arizona was believed to have been caused by unknown volcanic processes. It is also weird to think that until 1969 with the trips to the Moon, even lunar craters were regarded as volcanic in origin by most scientists. It is even weirder that a few scientists maintain that the only recognized catastrophic event that has occurred since the Earth was molten is the flood that created the channelled scablands in the northwestern US. As Shoemaker says in the video, "I had to teach myself that if one really pursues the observations, the world is telling us that things do fall out of the sky."
This video would be an excellent addition to the video library of all schools in order to educate and interest coming generations of scientists. In the context of his death not long after this video was completed, it becomes a fitting tribute and requiem. highly recommended
I wish I could say the same about the online experience NG built around this program, found here. It is geared toward schoolkids, and they may get something out of it, and it should keep them busy, but like a lot of efforts found out on the web it is mostly execution with very little content. There is one page of pointers to other related sites. There is also a picture from 1954 of a woman from Alabama who is the best known recent victim of meteorite impact to the body. This link is included because during the past week (it's March 22 1999) I found a statement on the web to the effect that no one has been hit by a meteorite in at least one thousand years, which is a quintessentially ignorant statement.
For information about a similar broadcast, featuring Eugene Shoemaker, Peter Thomas, Clark Chapman, and Victor Clube. try the transcript of PBS' NOVA episode The Doomsday Asteroid.
In the October 1998 issue of Reason there is an article and interview of Sallie Baliunas. Her stance against the stampede of global warming opponents is courageous and admirable. As far as Lixus is concerned, global warming has never been anything but a political axe to grind, and its diehard supporters are not acting as scientists when they try to warn us about it. These global warming allegations are nothing but a pursuit of funding and an attack on lifestyles.
Baliunas talks about the Maunder Minimum, a cycle of solar output and sunspot counts that has long been shown to correlate to the temperature cycle of the Earth's climate. She points out that the documented changes in solar output correlates with the temperature changes documented for this century and points out that the huge amounts of (so-called) greenhouse gases were released after the temperature had started its decline. Later she points out that the International Panel on Climate Change issued its report claiming that its models had predicted the temperature change, but that when the data used was analyzed the conclusions of the original report were shown to be phony.
[ update January 1999 from sci.astro usenet group - UCLA astronomy professor Roger Ulrich believes the sun could play a larger role in the Earth's climate than has been realized. He is the first scientist to make measurements of the sun's weak magnetic field over an extended period. While scientists had dismissed the sun as a factor in global warming, Ulrich said there may be a longer-term trend that has not been factored in coming from this 80 percent region of the sun. Ulrich thinks it is "reasonably likely" that the weak field plays a larger role than has been assumed. Ulrich noted that the number of sunspots has increased during this century. Ulrich's research is supported by NASA, the Office of Naval Research and the National Science Foundation. His colleagues are Judit Pap, UCLA research astronomer; and graduate student Daryl Parker. - Andrew Yee ayee@nova.astro.utoronto.ca ]
Baliunas also talks about the CHARA interferometer which may make it possible to detect planets around stars by direct observation. The resolution of the telescope is 100 times greater than the Hubble (but the Hubble can see farther). If successful, we'll no doubt see a stampede to build these types of telescopes at locations all over the world. In my opinion, the government funding currently wasted on these phony greenhouse effect studies should be terminated and directed toward these types of projects. - recommended
Thomas C. Van Flandern begins Dark Matter, Missing Planets, and New Comets with an articulation of his Meta Model of reality. In the rest of the book he theorizes that the explosion of a planet about three million years ago resulted in the debris we see today in the asteroid belt between Mars and Jupiter, as well as the various orbit crossing comets and asteroids. He discusses catastrophic bombardment, Planet X, eclipses, and other astronomical topics.
The new edition of his book claims that an earlier exploding planet, some 65 million years ago, contributed the debris that crashed into the Earth at Chicxulub and ended the dinosaurs. He also points out a recent discovery of a large impact in Argentina that dates to 3.3 million years ago, evidence for the more recent planetary explosion.
He expresses an open mind about the Face On Mars, despite the fact that the latest orbital observations showed it to be an artifact of the resolution of the much earlier Viking orbiter cameras. Don't let that view dissuade you from checking out the core of his work, such as his NEAR challenge in which he states that one of its consequences of his exploding planet theory "was the realization that natural satellites of asteroids and comets are commonplace" - recommended
Alan Alford wrote The Phoenix Solution regarding an exploded planet hypothesis of his own. He also has the idea (similar to other current works by other authors) that the Giza pyramids were constructed many thousands of years before the rise of what we know as ancient Egypt. "How might the Egyptians or their predecessors have worked out the exploded planet theory?" and "Legends of Atlantis reconsidered in the light of the Egyptian exploded planet cult" are among the topics listed in the online table of contents. Other features of the book include a critique of Zecharia Sitchin.
...some more exploded planet stuff by Richard C. Hoagland of the Enterprise Mission. This researcher is difficult for me to take seriously. He has been beating the drum about the Face On Mars, linking it to the Moon, the Sphinx, Atlantis, and I'm not sure what else is on his list. This page on his site is helpful in its discussion of the excess heat phenomena associated with the four largest solar planets, Jupiter, Saturn, Uranus, and Neptune, because it points out that the excess heat is anomalous and that three different explanations have been thought necessary.
Paul A. LaViolette was the first to predict that high intensity volleys of cosmic ray particles travel directly to our planet from distant sources in our Galaxy, a phenomenon now confirmed by scientific data. He is also the first to discover high concentrations of cosmic dust in Ice Age polar ice, indicating the occurrence of a global cosmic catastrophe in ancient times. Among his published works are Earth Under Fire and Beyond the Big Bang. The first of these claims that our ancient ancestors endured a catastrophe that originated in a galactic core explosion, and that they encoded a warning to future generations using the zodiac and the tarot. He also writes that the story of Atlantis and its armies was just a metaphor for the melting of the ice age glaciers. There is a website about these alleged warnings that was composed by a follower of the theory. At one point the author of that website asks, "If this message was so important to convey, why didn't the authors of the zodiac constellations arrange the zodiac signs so as to properly express their science of matter-energy creation? Why did they require that the recipient would have to rearrange the signs from the order they were presented along the ecliptic?" It seems to me that the answer is, the authors didn't do any such thing. My question is, if the message was so important, why would it be put into a code? If someone witnessed such an event, why cover it up? Sounds like a good reason to review Mankind In Amnesia. LaViolette and Alford (see above) agree a celestial catastrophe is the origin of humankind's most ancient myths and religions, but differ as to the cause.
In the book Rain of Iron and Ice, John S. Lewis examines the case for asteroid bombardment of the Earth. It sounds like the greatest threat lies in the near Earth asteroids, most of which travel along with us and are little known or studied and difficult to detect. Perhaps a nudge from a passing comet or maybe the tug of the Moon could bring one into the Earth's sphere of influence with catastrophic results and no warning. - recommended
On the site for Discover magazine, I found an article by Corey S. Powell regarding a new piece of bureaucracy from NASA. Powell didn't put it that way, I did. Donald Yeomans and staff plans to locate at least 90 percent of the near Earth objects of at least a kilometer in size by the year 2010. Also, "David Tholen and Robert Whiteley of the University of Hawaii recently announced the discovery of a new kind of asteroid whose orbit lies entirely within the orbit of the Earth." These types are not exactly a new discovery. Beginning in 1989, Tom Gehrels at the U of Arizona and his Spacewatch program used various techniques in a concerted effort to find asteroids and other space debris, and named those that have orbits similar to the Earth "Arjunas". Some of these orbits lie entirely within that of the Earth, and have diameters of 100 meters. [ Rain of Iron and Ice, p. 81, pp. 78- ]
How much danger is there from known NEOs? What is being done? "while the discovery rate is picking up, we still need a factor of ten improvement to complete the Survey within a decade."
Clark R. Chapman has published a number of scholarly papers regarding the small bodies that seem to be the greatest threat to human civilization and survival.
Near Earth Asteroid Tracking home page - nice pictures and data for amateur astronomers, especially amateur radioastronomers, since these objects tend to be small in the sky and radioastronomy can be used during any time of day or condition of weather.
Joseph Jochmans wrote Cosmic Collisions for issue six, winter 1996, of Atlantis Rising magazine. Although now out of date, and mixing Nostradamus and Edgar Cayce with observed near Earth objects, it is of some interest. He refers to an asteroid 1989C that I think should be 1989AC, and may also be a duplicate of another asteroid he mentions.

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