In the long discussion of water on the Moon, a new study contradicts(与……相矛盾)) some recent reports that say the Moon had water at the time of its formation. A group of researchers reported in the journal Science that when the Moon was created, some 4.5 billion years ago, there was not much hydrogen(氢气) on it, and therefore no water. The researchers surveyed and evaluated this by analyzing chlorine isotopes（氯同位素） found in lunar rock samples from Apollo missions. The range of chlorine isotopes in lunar samples was 25 times that found in samples from Earth. If the Moon had significant levels of hydrogen, as Earth did, this range would have been far less, said Zachary D Sharp, a scientist in the Department of Earth and Planetary Sciences at the University of new Mexico and the study’s lead authour. The chlorine would have stuck together with hydrogen, forming compounds like hydrogen chloride, and escaped from the Moon’s surface, he said. The abundance of chlorine indicates a lack of hydrogen and water. “ The amount of water on the Moon was too low for life to possibly have existed there,” he said. Most scientists believe the Moon was formed when a large object stuck  Earth, breaking off a chunk(a vast piece) that has since orbited Earth. On Earth, goes one theory, water was released as steam form molten basalts(玄武岩) over time, eventually forming bodies of water. “An understading of whether the Moon was dry or wet will help us understand how water appeared on Earth,” Dr Sharp said. 小题1: A new study indicates that _____ on the moorn.
A. Zachary D. Sharp, a scientist of New Mexico was in charge of the new study. B. Chlorine isotopes in lunar samples are 25 time larger than those on the Earth. C. The more aboundant chloride, the shorter hydrogen and water. D. The new study is benificial to understand how water appeared on Earth. 小题4: What can we learn from the passage?
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