Astronomy Chapter 7 & 8

The terrestrial planets are?
Mercury, Venus, Earth, and the Moon, Mars
The terrestrial planets are all made of?
Mostly, rock, metal
The parts of a terrestrial planet from the center out are?
Core, Mantle, Crust
All terrestrial planets have?
A solid surface
All terrestrial planets have?
Earth possesses few visible craters while the moon possesses many. This is because?
The moon doesn't have an atmosphere that could burn up many of the meteorites before impacting, Erosion and plate tectonics have slowly removed evidence of past cratering on earth
In the development of a planet, the stage of ? occurred when molten rock flowed through fissures and filled deep basins with molten rock.
Slow surface evolution is caused by?
Wind erosion and plate tectonics
Which of the following is not one of the four stages in the development of a terrestrial planet?
The youngest parts of Earth's crust are?
The midocean rifts
The plates of Earth's lithosphere move at speeds of?
A few cm per year
The Himalayas Mountains are rugged, jagged peaks and the Appalachians are smooth and rolling. Why is there a difference?
The Appalachians are much older and have been smoothed by erosion
The energy that moves the plates of Earth's crust comes from?
Convection from the hot interior
Diagram 20-1 shows a schematic of Earth. If an earthquake occurs at point X on Earth's surface, at which of the locations indicated by numbers would observers receive S waves from this earthquake?
1, 2, & 3
Saying that Earth's mantle is plastic means that?
It has the properties of a solid but is capable of flowing under pressure
Which of the following is not produced by plate tectonics?
Earth's magnetic field
The central regions of Earth's core are a solid because?
The pressure at the center raises the melting point
Which of the following provide evidence that Earth's core is at least partially molten?
S waves do not penetrate Earth's core
Earth's magnetic field is generated by the dynamo effect in the?
Molten metallic core
The gas this is most responsible from the greenhouse effect on Earth is?
Carbon Dioxide (CO2)
If Earth's average surface temp were to increase by several degrees?
Sea level would rise and flood coastal areas
The Van Allan belts are?
Composed of high energy particles from the solar wind that are trapped in Earth's magnetosphere
The graph below indicates the temp of Earth's atmosphere as a function of altitude. At what altitude is Earth's atmosphere the coldest?
100 km
Why would a decrease in the density of the ozone layer create a public health concern?
None of the above
Which of the following terrestrial planets does not have a significant atmosphere?
How are the scientists able to study the interior of the Earth?
They study seismic waves that travel through the interior of the Earth
What property does carbon dioxide have that makes it a greenhouse gas?
It easily absorbs infrared radiation
What is the most abundant gas in the Earth's atmosphere?
Slow surface evolution on the moon is limited to?
Low level meteorite impacts
The moon is no longer geologically active because?
It is too small
The Earth's moon is airless and inert because its mass is ? Earth's.
Much less than
The escape velocity of the Earth's moon is ? that of the Earth.
Less than
The lunar maria are?
The lava plains of the lunar lowlands
The presence of vesicular basalts among the lunar rock samples shows that?
Molten lava once flowed over the lunar surface
The presence of breccias among the lunar rock samples shows that?
The lunar surface was fragmented by meteorite impacts
The fission theory of the moon's origin has been criticized because?
The moon's composition is different from Earth's
As the moon revolves around the Earth,?
It keeps one side always toward Earth
Which hypothesis, concerning the formation of the moon, makes predictions that best fit the observed lunar data?
The large impact hypothesis
The condensation hypothesis for the formation of the moon suggests that the moon and Earth formed as a double planet from the same cloud within the solar nebula. This hypothesis predicts that?
The moon and Earth should have identical compositions and densities
The moon's highlands?
Are older than the maria
The time it takes Mercury to complete a solar day (the time from sunrise to sunrise)?
Is equal to two revolutions of Mercury around the sun
The Mercury has a large iron core is evidenced by?
The large mean density of Mercury
The surface temp of Mercury is?
None of the above
Why is it surprising that Mercury's magnetic field is strong enough to be measured (>>Earth's moon's), yet significantly weaker than Earth's magnetic field?
Mercury's small size suggests that it should no longer have a molten core, so no magnetic field is expected
In contrast to the Earth and Mercury, the fact that the Earth's moon has no magnetic field implies that?
The moon's core contains little if any molten iron
Mercury has a mass of 3.3x10<23 kg and a radius of 2.4x10<6 m. The gravitational constant is 6.7x10<-11 N m<2/kg<2. What is Mercury's escape velocity?
4.3 km/s
If Mercury is 1.5x10<8 km and has a diameter of 2,400 km, what is its angular diameter as viewed from Earth?
3.3 seconds of arc
The oldest parts of the surface of Mercury, that are listed below, are believed to be?
The intercrater plains
The theory that Mercury shrank slightly when it was young has been proposed to explain Mercury's?
Lobate scraps
The surface of Mercury is difficult to map from Earth because?
It is always near the sun
Slow surface evolution on Mercury is due to?
Micrometeorite impacts, Intense cycles of high and low temp that weakens the surface rocks
? are believed to have formed on Mercury when the planet's interior cooled and shrank.
Lobate scraps
The temp on the daylight side of Mercury?
Is about 400 degrees hotter than the night side because Mercury rotates very slowly
Which of the terrestrial planets has the most difficult time retaining an atmosphere?
Mercury's major atmospheric gas is?
Misleading; the atmosphere is virtually nonexistent
The moon's distance from Earth is measured very accurately by bouncing a laser beam off of a small mirror left on the surface of the moon. If a laser is fired at the moon and the signal returns in 2.6 seconds, what is the distance to the moon?
390,000 km
How does the large-impact hypothesis explain why the Moon is poor in heavy elements like iron?
The impact occurred after Earth had differentiated heavy elements to its center
Which of the terrestrial planets has lobate scraps seen as features on its surface?