comet-ImpactImpact debris and evidence of widespread wildfires around eastern North America suggest that a large space rock whacked Earth about 56 million years ago at the beginning of the Paleocene-Eocene Thermal Maximum, also known as the PETM, a period of rapid warming and rising carbon ...
【小题5】 created by the impact of comet(彗星) and small planets(3’) 解析分析:本文说明了科学家认为火星上存在生命。【小题1】根据Scientists believe that conditions on Mars around 3.8 billion years ago were very similar to those of the early earth when primitive organisms were spreading ...
multi-institutional 26-member team proposing a startling new theory: that an extraterrestrial impact, possibly a comet, set off a 1,000-year-long cold spell and wiped out or fragmented the prehistoric Clovis culture and a variety of animal genera across North America almost 13,000 years ago. ...
Huge impact may have left Mars 2-faced -- Scientists believe asteroid or comet blasted red planet 4 billion years agoAlicia Chang
Comet Shoemaker-Levy 9 impact on JupiterInfrared image of Jupiter showing the multiple impact sites in the southern hemisphere of Comet Shoemaker-Levy 9 in an image taken by the Infrared Telescope Facility, Mauna Kea, Hawaii, July 21, 1994. The bright spot in the top right of the image is...