论文标题
破碎彗星的危险
The hazard from fragmenting comets
论文作者
论文摘要
彗星瓦解是通过升华和离散分裂事件进行的。几天之内，彗星弹出的物质的横截面面积可能比地球大的倍，与与核本身的碰撞相比，与这种碎屑的相遇更大。在短时间内，大型彗星的分层碎片和升华可能会产生数百个这样的短寿命簇。我们对这种演变进行建模，以评估通过大气灰尘或多种影响可能产生重大陆地效应的相遇的概率。这种接触可能导致了大型动物的灭绝和12900年前的气候冷却，以及公元前2350年左右的文明崩溃。
Comet disintegration proceeds both through sublimation and discrete splitting events. The cross-sectional area of material ejected by a comet may, within days, become many times greater than that of the Earth, making encounters with such debris much more likely than collisions with the nucleus itself. The hierarchic fragmentation and sublimation of a large comet in a short period orbit may yield many hundreds of such short-lived clusters. We model this evolution with a view to assessing the probability of an encounter which might have significant terrestrial effects, through atmospheric dusting or multiple impacts. Such an encounter may have contributed to the large animal extinctions and sudden climatic cooling of 12,900 years ago, and the near-simultaneous collapse of civilisations around 2350 BC.
