jes1@akgub.UUCP (04/02/87)
Soon after the publication of his *Worlds in Collision* in 1950, Immanuel Velikovsky was accused of "creating new forces in nature to suit his needs." That same year, J.H. Oort suggested (speculated) that there is a diffuse cloud of gas, dust, and comets that is gravitationally part of our solar system some 40,000 times as far from the sun as the earth. He went on to suggest how many comets it contains, how it originated, and how it releases the comets that we observe passing through our part of the solar system. This is the most popular idea today on the origin of comets - even though it does not rest on a single shred of observational or theoretical evidence! During a recent conversation with a quite orthodox profes- sor of astronomy, I related that Velikovsky had concluded from an extensive analysis of *human records* that the earth had been dis- turbed in its motion by a planet-size comet some 3500 years ago. The professor responded with a patronizing smile and then chal- lenged, "But a comet that large has never been observed." Then I smiled and asked, "When was the Oort Cloud last observed?" He smiled again - but had nothing more to say. J.E. Strickling
jon@oddhack.UUCP (04/03/87)
In article <828@akgub.UUCP> jes1@akgub.UUCP (jes1) writes: >in nature to suit his needs." That same year, J.H. Oort suggested >(speculated) that there is a diffuse cloud of gas, dust, and comets >that is gravitationally part of our solar system some 40,000 times >as far from the sun as the earth. He went on to suggest how many >comets it contains, how it originated, and how it releases the >comets that we observe passing through our part of the solar system. >This is the most popular idea today on the origin of comets - even >though it does not rest on a single shred of observational or >theoretical evidence! This is utter bull. I have read Oort's original paper, and in fact have a copy handy in case people want references. His proposal rests on the observational evidence of cometary orbits whose aphelia cluster, and a model of stellar perturbations which shove bodies in the cloud into said cometary orbits. Of course, the theory has been considerably modified since originally proposed, taking into account galactic tides and giant molecular clouds among other things, but the basic concept is valid. > During a recent conversation with a quite orthodox profes- >sor of astronomy, I related that Velikovsky had concluded from an >extensive analysis of *human records* that the earth had been dis- >turbed in its motion by a planet-size comet some 3500 years ago. >The professor responded with a patronizing smile and then chal- >lenged, "But a comet that large has never been observed." Then I >smiled and asked, "When was the Oort Cloud last observed?" He >smiled again - but had nothing more to say. When did you last observe protons, for that matter? I hope weemba flames you properly for this idiocy; I don't feel up to using that sort of language. Finally, IRAS may in fact have OBSERVED a protocometary cloud. I saw a pretty convincing looking picture last term. I don't remember the target offhand but I can dig it up if need be. I see that, having been (thank God) more or less removed from sci.astro, the Velikovskites feel compelled to continue their nonsense in less-aware groups. A pity. Please do NOT cross post responses to sci.astro or sci.space. -- Jon Leech (jon@csvax.caltech.edu || ...seismo!cit-vax!jon) Caltech Computer Science Graphics Group __@/