It is thought that the Moon was forme d when a planet about the size of Mars struck the early Earth aroun d 4.5 billion years ago. T he pieces left over fro m years ago. T he pieces left over from the Moon. A t the time of its formation, the Moon was just 14000miles away fro...
(他们发现这些陨石的含水量极低——事实上,它们是地球以外测量到的最干燥的物质之一)"和第三段中的"These results,which let researchers rule them out as the primary source of the Earth's water (这些结果让研究人员排除了它们是地球水的主要来源的可能性)"可知,研究人员从融化的陨石中证明了它们不可能是...
The structure of the vortex system that could have occurred in the Earth's mantle resulting the temporary satellite immersion is considered in comparison with structure of the vortices around the submerged liquid jet in laboratory experiments. An assumption is made about the formation of a vortex ...
Professor: Last week, we discussed the formation of Earth and the other rocky planets, of the planets in the inner solar system. So what about the gas giants? Jupiter, Saturn, Uranus and Neptune. Well, there's two theories, but first, let's recap. ...
6. Which of the following satements is INCORRECT about David’s personal background? A.He had excellent academic records at school and university.? B.He was once on a PhD programme at Yale University.? C.He received professional training inacting9.?
Comets(彗星) are made from debris left over when our Solar System was formed.The solid part of a comet,the nucleus,is a chunk of ice typically measuring a few kilometres across.The ice in a comet is mainly made up of frozen ammonia,methane and water.Harvard University astronomer Fred L....
5 billion years ago" " The team of researchers analyzed seven melted meteorites that crashed into Earth during billions of years in our solar system.”可知.研究者通过分析熔化的 陨石来进行研究。 故选B. 3.D 细节理解题 由"This led them to conclude that water was likely delivered to Earth ...
Material that was blown from the coma to form the tail is lost from the comet forever. Consequently, it is believed that most comets cannot survive more than a few hundred close orbits of the Sun. Once all the gases are expelled, the remaining material—a swarm of tiny metallic and stony...
246K Learn the definition of an ocean basin. Understand the formation of oceanic ridges and trenches by plate tectonics. Discover four types of oceanic ridges. Related to this QuestionWhen was the Southern Ocean named? How did the Antarctic Ocean get its name? When was Antarctica ice free?
Previous evidence has shown that Earth’s moon was formed during this period, with one hypothesis being that a planetesimal known as Theia collided with Earth and debris from that collision formed the Moon. Timing of the orbital instability is important as it determines when some of the familiar...