The Fact That Earth’s Interior Is Differentiated Suggests That

Astronomy Chapter 6

The lithosphere of a planet is:its solid surface
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:Earth, Venus, Mercury
Compared to the dark-colored regions on the surface of the Moon, the light-colored regions are approximately:1 billion years older.
The age of the Solar System can be determined most accurately by:radioactive dating of rocks retrieved from the Moon
Which object would have the largest impact if it were to strike the Earth?An asteroid moving at 200m/s
Which of the following is a remnant from space that has hit the surface of the earth?Meteorite
Which of the following is NOT a factor that helps explain Earth’s lack of craters compared to the Moon?Higher density interior
The smallest craters are found on:the Moon
Mars, Venus, and Earth are much less heavily cratered than Mercury and the Moon. This is explained by the fact that:Mars, Venus, and Earth were geologically active longer than Mercury and the moon
Studies of the amount of cratering at different locations on the Moon indicate that:the rate of cratering in the Solar System has changed dramatically over time.
Based on the age of the light- and dark-colored regions of the Moon and the number of craters observed in these regions, we know that impacts in the inner Solar System:rapidly decreased approximately 3 billion years ago
What type of wave is depicted in the figure below?Transverse
Differentiation refers to materials that are separate based on their:density
What type of wave is depicted in the figure below? 2Longitudinal
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:part of the planet’s interior is liquid.
The fact that Earth’s interior is differentiated suggests that:it was liquid at some point in the past.
Roughly how often does a high tide occur?Once every 12 hours.
The current theory is that a planet will have a strong magnetic field if it has:fast rotation and a liquid core
Which of the following is NOT a requirement for a planetary magnetic field?Solid iron core
In the past, the Moon was closer to the Earth and the difference in the heights of the ocean at high and low tides were:larger
Neap tide occurs when the Moon is in the first or third quarter phase and results in:smaller than usual tides.
What is the best explanation for the heating of Earth’s interior today?Decay of radioactive elements
Which of the following will NOT be a consequence of Earth’s consumption of the bulk of its radioactive “Fuel” in the future?Earth will spin more slowly on its axis.
Earth’s innermost core is solid, not liquid, because:all the liquid has moved up into the mantle via convection.
Mars has a diameter that is approx half 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?Mars’ heating rate is .12 times that of Earth’s.
Based on the assumption that a liquid, conducting core and rapid rotation are both required for a magnetic field to operate, which terrestrial planets would you expect to have magnetic fields?Earth and Mars only.
Continental drift occurs at a typical rate of a few:cm/year.
What would you study in order to determine the timescale on which the Earth’s magnetic field reverses direction?A spreading center on the sea floor
Plate tectonics is NOT responsible for the formation of:canyons.
The North American Plate and the Pacific Plate are sliding past one another at a rate of approximately 3 cm/year. San francisco, which is located on the edge of the North American Plate, is sliding southward toward Los Angeles, which is located on the Pacific Plate. If they are currently separated by a distance of 600 km, how many years will it take for the two cities to meet?20 million years
If the Himalaya mountain range is presently 8,000 m in height and is rising at a rate of .5 m per century because of the convergence of two continental plates, how long did it take to create this mountain range?1.6 million years
Which of the following are sites of volcanic activity on Earth?All of the above.
The largest volcanic mountains in the solar system are found on:Mars
Which terrestrial planet shows the least evidence of recent volcanic activity?Mercury
Which of the following does NOT contribute to the large size of Mars’s volcanoes?Lack of atmosphere.
Erosion on the surface of the Moon is primarily caused by:solar radiation
We suspect that Mars once had liquid water on its surface because:All of the above
We have direct evidence for the current existence of water on the surface of which terrestrial object?Mars
Flows of material surrounding Martian craters suggest:the presence of water in surface rocks
The rovers named Spirit and Opportunity that recently explored Mars’s surface discovered:minerals that must have formed in an environment rich in liquid water.
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?One-sixteenth
If you obtained a sample of rock from Venus and determined the abundances of 238U and 207Pb in it, and found that for every 1 uranium atom there were 3 lead atoms, then what would the age of this rock be?1.4 billion years
Compare two blackbody objects, one at 200k and one at 400k. how much larger is the flux from the 400k object, compared to the flux from the 200k object?Sixteen times as much
As a blackbody becomes hotter, it also becomes ______ and ________.more luminous; bluer
At what wavelength does your body radiate the most given that your temperature is approximately that of the Earth, which is 300K?10^-5 m
What is the surface temperature of a star that has a peak wavelength of 290 nm?10,000 K