| タイトル | Comets and the origin of the solar system - Reading the Rosetta Stone |
| 著者（英） | Weissman, Paul R.; Mumma, Michael J.; Stern, S. A. |
| 著者所属（英） | NASA Goddard Space Flight Center; NASA Headquarters; Jet Propulsion Lab., California Inst. of Tech. |
| 発行日 | 1993-01-01
1993 |
| 言語 | eng |
| 内容記述 | It is argued that, from the measured volatile abundances, comets formed at temperatures near or below about 60 K and possibly as low as about 25 K. Grains in Comet Halley were found to be of two types: silicates and organics. Isotopic evidence shows that Comet Halley formed from material with the same compositional mix as the rest of the solar system, and is consistent with comets having been a major contributor to the volatile reservoirs on the terrestrial planets. A variety of processes have been shown to modify and reprocess the outer layers of comets both during their long residence time in the Oort cloud and following their entry back into the planetary system. The most likely formation site for comets is in the Uranus-Neptune zone or just beyond, with dynamical ejection by the growing protoplanets to distant orbits to form the Oort cloud. A substantial flux of interstellar comets was likely created by the same process, and may be detectable if cometary formation is common in planetary systems around other stars. |
| NASA分類 | ASTROPHYSICS |
| レポートNO | 93A42971 |
| 権利 | Copyright |
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