UNIVERSE
PLANETARY INTERIORS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -Earth’s volcanic moon Until about 1 billion years ago, the moon’s nearside was volcanic. The dark, basaltic planes called lunar maria. ("seas” in Latin) that can still be seen on the moon’s surface were formed by ancient volcanism. The last of the large impacts also probably happened around this time.
Detailed explanation-2: -Moon Becomes Geologically Inactive. Lunar volcanism decreased significantly by 3 billion years ago and ceased completely by about 1 billion years ago as the interior of this small body cooled.
Detailed explanation-3: -When did the Moon form? Scientists believe the moon formed during a giant impact about 60-175 million years after the solar system was born. To arrive at this estimate, they can use rocks from Earth.
Detailed explanation-4: -Approximately one billion years ago, the Moon orbited the Earth much closer than it does today. The radius of the orbit was only 24400 km. Today, the radius is 385000 km. The orbital period was only 23400 s.