Exam 7: The Terrestrial Planets and Earths Moon

The Mars rovers named Spirit and Opportunity found evidence in the chemical makeup of the rocks that proves Mars had liquid water on its surface in the past.

Mars has a diameter that is approximately half that of Earth's.If the interiors of these planets are heated by radioactive decays,how does the heating rate of Mars' interior compare to that of Earth's?

How does the radioactive heating of Earth vary from when it was first formed 4.6 billion years ago until today?

We have direct evidence for the current existence of water on the surface of which terrestrial object?

Flows of material surrounding Martian craters suggest

If you obtained a sample of Martian rock,determined the abundances of and in it,and found that for every 1 uranium atom there were 7 lead atoms,then what would the age of this rock be? Note that decays to with a half-life of 700 million years.Assume that there was no in the rock when it originally formed.

The rovers named Spirit and Opportunity that recently explored Mars' surface discovered

If a radioactive element has a half-life of 10,000 years,what fraction of it is left in a rock after 40,000 years?

How do we know that Earth's magnetic field has flipped its polarity many times in the past?

Suppose an earthquake occurs on an imaginary planet.Scientists on the other side of the planet detect primary waves but not secondary waves after the quake occurs.This suggests that

The maria on the Moon's surface are approximately 1 billion years younger than the rest of its surface.

Mars,Venus,and Earth are much less heavily cratered than Mercury and the Moon.This is explained by the fact that

What are two materials present in the K-T boundary that support the idea that a 10 km-wide asteroid or comet hit the Yucatán peninsula and caused or accelerated the extinction of 70 percent of all living species on the Earth? Explain where these two materials came from.How long ago did this happen?

Compared to the dark-colored regions on the surface of the Moon,the light-colored regions are approximately

The interior of the Earth is differentiated because it cooled very quickly.

Which object would have the largest impact if it were to strike the Earth?

Continental drift occurs at a typical rate of a few

Based on the number of impact craters observed per square meter on their surface,place these terrestrial planets in order of youngest to oldest surface:

Which planet would you expect to have a larger molten core,a planet of Earth's size or a planet that had half the radius of Earth? Explain why.

Describe the difference between seismic primary and secondary waves and why this difference makes them useful in probing the structure of the Earth's interior.