Mumma M J, Dello Russo N, DiSanti M A, Magee-Sauer K, Novak R E, Brittain S, Rettig T, McLean I S, Reuter D C, Xu L H
Laboratory for Extraterrestrial Physics, Code 690, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
Science. 2001 May 18;292(5520):1334-9. doi: 10.1126/science.1058929.
In the current paradigm, Oort cloud comets formed in the giant planets' region of the solar nebula, where temperatures and other conditions varied greatly. The measured compositions of four such comets (Halley, Hyakutake, Hale-Bopp, and Lee) are consistent with formation from interstellar ices in the cold nebular region beyond Uranus. The composition of comet C/1999 S4 (LINEAR) differs greatly, which suggests that its ices condensed from processed nebular gas, probably in the Jupiter-Saturn region. Its unusual organic composition may require reevaluation of the prebiotic organic material delivered to the young Earth by comets.
在当前的范式中，奥尔特云彗星形成于太阳星云的巨行星区域，那里的温度和其他条件差异很大。四颗此类彗星（哈雷彗星、百武彗星、海尔-波普彗星和利彗星）的测量成分与天王星以外寒冷星云区域的星际冰形成一致。彗星C/1999 S4（LINEAR）的成分差异很大，这表明其冰是由经过处理的星云气体凝结而成的，可能是在木星-土星区域。其不寻常的有机成分可能需要重新评估彗星输送到年轻地球的益生元有机物质。
