Astronomy 104 Homework 7

Which terrestrial object shows the least evidence of recent volcanic activity?

Mercury

_________ in our atmosphere is a direct consequence of the emergence of life.

Oxygen

If you could find a large enough ocean, which one of these planets would float in it?

Saturn

Earth's innermost core is solid, not liquid, because

the pressure is too high for the material to be in a liquid state.

Jupiter is approximately _______ times more massive than Earth.

300

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

Mars

If the carbon dioxide in Earth's rocks were suddenly released into its atmosphere, what would happen?

It would cause a runaway greenhouse effect.

What is the reason Mercury has so little gas in its atmosphere?

Its mass is small & It has a high temperature & It is close to the Sun & Its escape velocity is low.

The largest volcanic mountains in the Solar System are found on

Mars

The Moon has a diameter that is approximately one-fourth that of Earth. If these objects' interiors are heated by radioactive decays and the total amount of energy in decays is proportional to the object's volume, how does the amount of internal heat the Moon has compare to that of Earth?

The Moon's heating rate is 1/64 times that of Earth's.

Venus and Earth probably formed with similar amounts of carbon dioxide in their secondary atmospheres. Which of the following is true?

The majority of Earth's carbon was absorbed by plants during photosynthesis & carbon is now bound up in rock, whereas Venus's remains in its atmosphere.

Which is not a reason that we suspect Mars once had liquid water on its surface?

The observed presence of water ice in Mars's polar ice caps.

Which of the following statements is false?

The surface of Venus has very few craters primarily because asteroids burn up in its thick atmosphere.

Why are Jupiter and Saturn not perfectly spherical?

They rotate rapidly.

Why did the terrestrial planets lose the majority of the gas in their primary atmospheres?

They were too hot and their escape velocities too low to hold onto them.

In the absence of a greenhouse effect, what would happen to Earth's oceans?

They would freeze over

When you look at the visible surface of a gas giant planet, you are looking at that planet's

atmosphere.

The main greenhouse gases in the atmosphere of the terrestrial planets are

carbon dioxide and water vapor.

In the absence of the greenhouse effect, the water on the surface of Earth would

freeze

The gas giants are made primarily of

molecular hydrogen and helium

If photosynthesis were to disappear on Earth,

oxygen would disappear from the atmosphere

Which of the following processes did ​not​ contribute gas to Earth's secondary atmosphere?

solar winds

The greenhouse effect is the

trapping of infrared radiation by the atmosphere

The presence of gases such as carbon dioxide and water vapor in a planet's atmosphere is direct evidence of _________ in a planet's history.

volcanic activity