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I guess the suspense now is, when will some idiotic moron arrive to add "callingartbell" to the keywords?
Small Comets and Our Origins
University of Iowa | circa 1999 | Louis A. Frank
Posted on 10/19/2004 11:13:25 PM PDT by SunkenCiv
http://www.freerepublic.com/focus/bloggers/1250694/posts
An Argument for the Cometary Origin of the Biosphere
American Scientist | September-October 2001 | Armand H. Delsemme
Posted on 09/06/2004 11:16:38 AM EDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1208497/posts
Great Impact Debate II: Much Ado About Nothing?Benny Peiser: I am not so sure about the accurateness of the claim that "no one in recorded history has been killed by an asteroid or comet." As a matter of fact, there are historical records that give accounts of suspected meteorite impacts leading to fatalities. For example, a number of historical reports exist about an alleged disaster in 1490 AD, said to have occurred in the Chinese city of Qingyang (Shaanxi province). According to these reports, over 10,000 people were killed when "stones fell from the sky like rain." Perhaps, as John Lewis has suggested in his book "Rain of Iron and Ice" (1996), it would be wiser to say, "No one in recorded history has ever been killed by a meteorite in the presence of a meteorite scientist and a medical doctor".
February 17, 2003
Great Impact Debate III: The Large and the SmallClark Chapman: Despite the fluctuating headlines in often inaccurate media stories, estimates of the relative risks due to comets and asteroids of various sizes has changed little in the last decade. Roughly 80 percent of the impact hazard is due to asteroids between 1 and several kilometers in diameter. About another 10 percent is due to an asteroid smaller than a kilometer striking the ocean and causing a tsunami. Roughly another 10 percent is due to comets, and less than 1 percent is due to small asteroids striking the land. So it is sensible that NASA finally decided, in 1998, to endorse the Spaceguard Survey goal of emphasizing searches for the NEAs greater than 1 kilometer (though the survey also finds smaller NEAs and comets).
February 24, 2003
Great Impact Debate IV: Collision Course for EarthJoe Veverka: I believe that we currently are not in a position to protect Earth from impacts by one kilometer-sized objects. The technology required to carry out such a task exists, or it can be developed, but the effort would be colossal by any standards... In such a discussion, it is essential to define a "horizon of concern." In other words, how far into the future does it make sense to worry about something and take precautions? ...It is only when we get down to impacts that occurred early in the 20th century that it makes sense to discuss mitigation - for example, the Tunguska explosion of 1908 that has been attributed to a meteoroid 60 meters in diameter. But even for these events, which might occur every few hundred to a thousand years, the cost of a mitigation policy must be weighed against the likely benefit.
March 3, 2003
Great Impact Debate V: EncoreAlan Harris: Such asteroids pass near the Earth many times before they impact. The objective of the Spaceguard Survey is to discover asteroids as they pass by the Earth on one of those prior occasions, which is exactly what happened with 2002 EM7. Whether the asteroid was discovered while approaching or receding is not a major issue... The main difference applies to objects just barely big enough to penetrate the Earth's atmosphere, like the Tunguska event. We can conclude the Tunguska cosmic body was a "hard stone" asteroidal object, because if it had been soft and fluffy it would have exploded at a much higher altitude than it did. Likewise, an iron body would have hit the ground and produced a crater about the size of Meteor Crater in Arizona. But for larger objects, the nature of the impactor hardly matters. A 1 kilometer-diameter object will punch right through the atmosphere regardless of its velocity or composition. So if it is that large, there is not much difference in effect between iron, rock, or a snowball of the same mass.
March 10, 2003
Dr. Peiser used to moderate Cambridge Conference Network a forum about catastrophism and Global Warming (big time skepticism). One of the best forums ever on the net.
Wrong thread...again!
