Astronomy (7-12) hw questions
When viewed through a telescope, Uranus and Neptune are distinctly bluish green in color. What gas is responsible for this striking appearance? Choose one: A. methane B. water C. hydrogen D. helium
A. methane
Geologists can find the actual age of features on a world by Choose one or more: A. radioactive dating of rocks retrieved from the world. B. assuming that all features on a planetary surface are the same age. C. comparing cratering counts on one world to those on another.
A. radioactive dating of rocks retrieved from the world. C. comparing cratering counts on one world to those on another.
The words weather and climate Choose one or more: A. refer to very different time scales. B. mean essentially the same thing. C. refer to very different size scales.
A. refer to very different time scales. C. refer to very different size scales.
Rank the parts of a comet by size, from smallest to largest. - tail - nucleus - coma
*smallest* 1. nucleus 2. coma 3. tail *largest*
Rank these four Solar System bodies in order of their periods, from shortest to longest. - Hale-Bopp - Jupiter - Encke - Saturn
1. Encke 2. Jupiter 3. Saturn 4. Hale-Bopp
The search for extrasolar planets has uncovered a phenomenon astronomers call a "hot Jupiter." If our Solar System had one, where would it orbit, relative to the other planets? (list them closest from the sun to farthest from the sun) • Hot Jupiter • Jupiter • Earth • Venus • Mars • Mercury
1. Hot Jupiter 2. Mercury 3. Venus 4. Earth 5. Mars 6. Jupiter
Select the ways in which Titan resembles early Earth. Choose one or more: A. It has terrain similar to Earth's. B. It has liquid water on the surface. C. Its atmosphere is mostly nitrogen. D. It has a thick atmosphere. E. It is rich in organic compounds.
A. It has terrain similar to Earth's. C. Its atmosphere is mostly nitrogen. D. It has a thick atmosphere. E. It is rich in organic compounds.
Why are Ganymede and Callisto geologically dead while the other two Galilean moons of Jupiter are active? Choose one: A. They are farther from Jupiter. B. They have retrograde orbits. C. They are more massive. D. They are larger.
A. They are farther from Jupiter.
If rings are observed around a planet, this indicates that Choose one: A. there is a recent source of ring material. B. the planet is newly formed. C. the rings are made of fine dust. D. the rings formed with the planet.
A. there is a recent source of ring material.
If a moon revolves opposite to a planet's rotation, it probably Choose one: A. was captured after the planet formed. B. had its orbit altered by a collision. C. formed very recently in the Solar System's history. D. has a different composition than other moons.
A. was captured after the planet formed.
Of the four large Galilean moons orbiting Jupiter, Io is the closest to the planet. Considering Io's size and location in the Solar System, what is the most likely reason for Io's high level of geological activity? Choose one: A. Io's proximity to the Sun provides a current source of internal heat. B. Io's proximity to Jupiter provides a current source of internal heat. C. Io must have more radioactive elements inside of it that provide a current source of internal heat. D. Io must be made of a substance that traps heat better, so it has still retained all of its initial internal heat from its formation.
B. Io's proximity to Jupiter provides a current source of internal heat.
Which of the following worlds does not show evidence of the current presence of liquid or frozen water? Choose one: A. Earth B. Venus C. the Moon D. Mars E. Mercury
B. Venus
Imagine that a star-forming cloud collapses but retains all of its mass in a single blob. In order to conserve angular momentum, the cloud must Choose one: A. come to a complete stop. B. spin faster. C. spin at the same rate. D. spin slower.
B. spin faster
The oxygen molecules in Earth's atmosphere Choose one: A. are being rapidly depleted by the burning of fossil fuels. B. arose when the secondary atmosphere formed. C. are the result of life. D. were part of the primary atmosphere.
C. are the result of life.
What causes the auroras of the giant planets? Choose one or more: A. strong electrical currents B. tilted magnetic fields C. charged particles D. strong magnetic fields
C. charged particles D. strong magnetic fields
Individual cloud layers in the giant planets have different compositions. This happens because Choose one: A. the Coriolis effect only occurs close to the "surface" of the inner core. B. there is no convection on the giant planets. C. different volatiles freeze out at different temperatures. D. the winds are all in the outermost layer.
C. different volatiles freeze out at different temperatures.
What determines an asteroid's shape? Choose one: A. All of the asteroids have irregular shapes but come in a range of sizes. B. Asteroids have a range of sizes, with the smallest being spherical and the larger ones irregular in shape. C. All of the asteroids have irregular shapes and are similar in size. D. Asteroids have a range of sizes, with the largest being spherical and the smaller ones irregular in shape.
D. Asteroids have a range of sizes, with the largest being spherical and the smaller ones irregular in shape.
Why do Jupiter and Saturn have no blue methane cloud tops? Choose one: A. There was no methane in the solar nebula at the location where Jupiter and Saturn formed. B. Methane can only condense deeper inside the planets, but the upper layers obstruct our view of it. C. They are too cold for methane to condense. D. They are too warm for methane to condense.
D. They are too warm for methane to condense.
Scientists determine the geological history of the moons of the outer planets from Choose one: A. seismic probing. B. time-lapse photography. C. radioactive dating. D. surface features.
D. surface features.
Which is not a reason for the large size of volcanoes on Mars compared to Earth's smaller volcanoes? Choose one: A. lower surface gravity on Mars than Earth B. many repeated eruptions on Mars C. absence of plate tectonics on Mars D. distance from the Sun
D. distance from the Sun
On which of the following does plate tectonics occur? Choose one or more: A. Earth B. Mercury C. Moon D. Venus E. Mars
A. Earth
Why is Jupiter reddish in color? Choose one: A. because of the composition of its atmosphere B. because it is moving away from Earth very quickly C. because it is very hot D. because it is rusty, like Mars
A. because of the composition of its atmosphere
Stellar occultations are the most accurate way to measure the _________ of a Solar System object. Choose one: A. diameter B. temperature C. density D. mass
A. diameter
Observations show that, in general, larger planets and moons have had geological activity more recently than smaller bodies have. All of the planets show past signs of volcanism, tectonics, and/or erosion, but only the larger ones are still geologically active today. Why is this? One reason has to do with the planet's interior. Most of the heat inside of Earth is left over from the accretion process during Earth's formation. What would you expect to have happened as the Earth (or any other planet) cooled after its formation? Choose one: A. The energy loss caused the planet to drift closer to the Sun, heating it and therefore increasing the level of volcanism/tectonics. B. The hard crust thickened, closing off volcanic vents, and the mantle began to solidify, slowing the motion that causes volcanism and tectonics. C. The planet spun more slowly, decreasing the winds and weakening the erosion. D. The hard crust became thinner, cracking more easily, and the mantle moved more freely, increasing the motion that causes volcanism and tectonics.
B. The hard crust thickened, closing off volcanic vents, and the mantle began to solidify, slowing the motion that causes volcanism and tectonics.
The greenhouse effect plays a major role in the climate of a planet. Visit the Greenhouse Effect AstroTour, and use what you learn there to choose all the statements below that are correct. Note that 273 K = 0°C = 32°F. Choose one or more: A. The Earth absorbs sunlight and reemits it in the ultraviolet. B. The more carbon dioxide there is in an atmosphere, the stronger the greenhouse effect will be. C. The Earth has reached thermal equilibrium, emitting the same amount of energy into space as it absorbs from the Sun. D. It would be beneficial to humanity to develop technology that would eliminate the greenhouse effect on Earth. E. If there were no greenhouse effect, liquid water would not exist on the surface of the Earth.
B. The more carbon dioxide there is in an atmosphere, the stronger the greenhouse effect will be. C. The Earth has reached thermal equilibrium, emitting the same amount of energy into space as it absorbs from the Sun. E. If there were no greenhouse effect, liquid water would not exist on the surface of the Earth.
Aside from their periods, short- and long-period comets differ because short-period comets Choose one: A. come closer to the Sun at closest approach than long-period comets do. B. mostly orbit prograde, while long-period comets have either prograde or retrograde orbits. C. contain less ice, while long-period comets contain more. D. do not develop ion tails, while long-period comets do.
B. mostly orbit prograde, while long-period comets have either prograde or retrograde orbits.
It is unlikely that the Moon formed elsewhere and was captured by Earth's gravity, since it may be impossible for the Earth to capture an object as large as the Moon. It is also of note that the Moon contains an unusually low quantity of volatiles, which are materials like water that are easily vaporized at high enough temperatures. Based on this, and given the moon's density, which of the following formation scenarios of the Moon most closely matches our observations? Choose one: A. The Moon was formed from the material of an enormous volcanic eruption on Earth. B. The Moon formed at the same time as, but separately from, the Earth from the same Solar Nebula material. C. The Moon accreted from the debris of the impact of a large object with the surface of the Earth. D. The Moon formed from the outer part of Earth's atmosphere.
C. The Moon accreted from the debris of the impact of a large object with the surface of the Earth.
What are other possible sources of Earth's water? Choose one or more: A. Early on, our Solar System passed through a fog-like cloud of water as it orbited the galaxy. B. When our Sun turned on, it caused melted ice to rain on Earth from the outer Solar System. C. The water was brought to Earth by collisions with icy planetesimals that formed near Jupiter. D. The water was bound together with minerals as Earth formed, and it was released during collisions.
C. The water was brought to Earth by collisions with icy planetesimals that formed near Jupiter. D. The water was bound together with minerals as Earth formed, and it was released during collisions.
Kuiper Belt objects (KBOs) are actually comet nuclei. Why do they not display comas and tails? Choose one: A. They are too close to the Sun. B. The comas and tails are pointing away from Earth. C. They are too far from the Sun. D. Most of the material has already been stripped from the objects.
C. They are too far from the Sun.
Venus and Earth are similar in size, so they should have had similar amounts of volcanic outgassing adding to the atmosphere, and similar gravities resulting in a similar loss of atmospheric gas to space. Why, then, are their atmospheres so different? This table shows the composition of the planets' atmospheres if all the carbon dioxide that exists anywhere on the planet were included. Carbon dioxide is added to the atmosphere through volcanic outgassing, and it is removed as it is absorbed by liquid water and then chemically combined with rock. Based on the text above and what you see in the table, what is the most likely reason Venus has a stronger greenhouse effect than Earth? Choose one: A. Venus is covered in clouds that reflect most of the sunlight away. B. Venus has a higher percentage of nitrogen than the Earth. C. Venus is closer to the Sun, so any liquid water that might have existed on the surface in the distant past would have evaporated away faster than on the Earth. D. Venus had more carbon dioxide added to the air through volcanic outgassing.
C. Venus is closer to the Sun, so any liquid water that might have existed on the surface in the distant past would have evaporated away faster than on the Earth.
Uranus is visible to the naked eye, a bit brighter than the faintest naked-eye stars. However, it was not until well after the invention of the telescope in the late 18th century that Uranus was accidently discovered. How could people have missed this naked-eye planet until then? Compare Uranus's properties in the following chart to the other planets, then select the option that could explain why Uranus was harder to discover. Choose one: A. Its rotation axis is tilted nearly on its side (high obliquity). B. It has a longer rotation period than Jupiter and Saturn. C. None of the listed properties should have any effect on its ease of discovery. D. It has a longer orbital period than Jupiter and Saturn.
D. It has a longer orbital period than Jupiter and Saturn.
Sort each of the planets according to its basic composition. (Gaseous, Rocky, and Rock/Ice) • Pluto • Venus • Jupiter • Uranus • Ceres • Neptune • Saturn • Eris • Mercury • Mars • Earth
Gaseous: Jupiter, Saturn, Uranus, Neptune Rocky: Mercury, Venus, Earth, Mars, Ceres Rock/ice mixture: Pluto, Eris
Why would bringing a sample back to Earth for analysis yield a more accurate age estimate for more recent volcanic activity? Choose one: A. Astronomers could use radiometric dating on the rocks. B. Astronomers could look for fossilized remains of life forms in the rocks to get an age. C. Astronomers could melt the rocks again to properly date the resulting lava. D. Astronomers could accurately measure the reflectivity of the rocks to get an age.
A. Astronomers could use radiometric dating on the rocks.
If we experience a year that is much hotter than the previous year, this means that Earth is going through a global warming trend, where the temperature will now continually increase each year. Choose one: A. It is impossible to tell with one year of data. B. false C. true
A. It is impossible to tell with one year of data.
Why did scientists suspect that the Moon cooled quickly? Choose one: A. It is small. B. It has no atmosphere. C. It has no significant amounts of water on the surface. D. It moves fast as it orbits the Earth and the Sun.
A. It is small.
Comparing objects in our Solar System can give us important clues toward understanding their properties that we wouldn't obtain through just studying each object independently. Comparing Earth's Moon to those of the other planets may also help us understand more about it. Choose one or more: A. Only half of the inner planets have moons. B. The Earth's moon is unique in that it is less dense than the moons of the other inner planets. C. The Earth's moon is typical in all ways when compared to the moons of the other inner planets. D. The Earth's moon is unique in that it is much larger than the moons of the other inner planets.
A. Only half of the inner planets have moons. D. The Earth's moon is unique in that it is much larger than the moons of the other inner planets.
Which of the giant planets has the most extreme seasons? Choose one: A. Uranus B. Jupiter C. Saturn D. Neptune
A. Uranus
What is an accretion disk, and what are its characteristics? Select the true statements regarding accretion disks. Choose one or more: A. An accretion disk forms because there is nothing to stop the collapse of an interstellar cloud toward its axis of rotation. B. An accretion disk's radius is typically hundreds of AU. C. Conservation of angular momentum leads a cloud to form a disk rather than collapse entirely. D. The shape and motion of the accretion disk are the reason that the subsequently formed planets all orbit in or near the equatorial plane of the star. E. Most of the material in an accretion disk that does not end up in the protostar is available to form its planets.
B. An accretion disk's radius is typically hundreds of AU. C. Conservation of angular momentum leads a cloud to form a disk rather than collapse entirely. D. The shape and motion of the accretion disk are the reason that the subsequently formed planets all orbit in or near the equatorial plane of the star.
The level of each of the surface-shaping processes that occur on a planet throughout its history will determine how its surface appears. The terrestrial planets were formed in basically the same environment, so we can assume that the average frequency of impacts for all of the terrestrial planets has been about the same. In a hypothetical scenario where impacts are the only process that ever shape planetary surfaces, how would the surfaces of the terrestrial planets compare? (Tip: Note that "craters per area" refers to the number of craters in the same-sized region on each planet—for example, craters per square meter.) Choose one: A. The smaller planets would have more craters per area than the larger planets. B. The planets closer to the Sun would have significantly more craters per area than the more distant planets. C. All of the planets would have roughly the same number of craters per area. D. The larger planets would have more craters per area than the smaller planets.
C. All of the planets would have roughly the same number of craters per area.
Why has the Great Red Spot been seen for only 400 years? Choose one: A. The spot began 400 years ago. B. Prior to 400 years ago, that side of Jupiter faced away from Earth. C. It was 400 years ago that Jupiter was first examined through a telescope. D. The planet Jupiter was discovered 400 years ago.
C. It was 400 years ago that Jupiter was first examined through a telescope.
Auroras are the result of Choose one: A. upper-atmosphere lightning strikes. B. the interaction of Earth's magnetic field with Earth's atmosphere. C. the interaction of particles from the Sun and Earth's atmosphere and magnetic field. D. destruction of stratospheric ozone, which leaves a hole.
C. the interaction of particles from the Sun and Earth's atmosphere and magnetic field.
Study the sizes of the gas giants (the distance from the Sun increases from left to right), and choose the best explanation that accounts for their differences in size. Choose one: A. Gas giants increase in size with increased distance from the Sun because the Solar Nebula was denser farther out. B. Gas giants increase in size with increased distance from the Sun because more types of materials could condense farther out. C. Gas giants decrease in size with increased distance from the Sun because fewer types of materials could condense farther out. D. Gas giants decrease in size with increased distance from the Sun because the Solar Nebula was less dense farther out.
D. Gas giants decrease in size with increased distance from the Sun because the Solar Nebula was less dense farther out.
*Perihelion* and *aphelion* describe the points in an orbit that are ______________________________________ (respectively) the Sun.
closest to and farthest from
Rank these hypothetical moons from oldest to youngest based on their cratering. You can assume the moons have never been volcanically active. - a moon partially covered with craters - a moon completely covered in craters, old and new - a moon with very few craters
*oldest* 1. a moon completely covered in craters, old and new 2. a moon partially covered with craters 3. a moon with very few craters *youngest*
Place in chronological order the following steps in the formation and evolution of Earth's atmosphere: • Volcanoes, comets, and asteroids increase the inventory of volatile matter. • Hydrogen and helium are lost from the atmosphere. • Plant life converts CO2 to oxygen. • Life releases CO2 from the subsurface into the atmosphere. • Hydrogen and helium are captured from the protoplanetary disk. • Oxygen enables the growth of new life-forms.
1. Hydrogen and helium are captured from the protoplanetary disk. 2. Hydrogen and helium are lost from the atmosphere. 3. Volcanoes, comets, and asteroids increase the inventory of volatile matter. 4. Life releases CO2 from the subsurface into the atmosphere. 5. Plant life converts CO2 to oxygen. 6. Oxygen enables the growth of new life-forms.
Rank, from greatest (at top) to smallest (at bottom), the seasonal variations of the terrestrial planets. • Venus • Mars • Mercury • Earth
1. Mars 2. Earth 3. Venus 4. Mercury
Uranus's orbit did not appear to behave according to Newton's laws of motion and gravity. The most likely culprit for Uranus's misbehaving orbit was the gravitational influence of another planet. Using Newton's laws, astronomers were able to calculate exactly where they would expect this still-undiscovered planet to be. When telescopes were pointed at this position, Neptune was seen. What does this imply? Choose one: A. Newton's laws have been verified by yet another test, so we should use them with high confidence until and unless they are falsified by future tests. B. Newton's laws have been verified by yet another test, but there is still not enough evidence for them, so they should be treated with cautious skepticism. C. Newton's laws have been falsified. D. Newton's laws have been verified as absolute truth.
A. Newton's laws have been verified by yet another test, so we should use them with high confidence until and unless they are falsified by future tests.
In 1910, Earth passed through the tail of Comet Halley. Among the various gases in the tail was hydrogen cyanide (HCN), which is deadly to humans. Yet nobody became ill from this event. Why not? Choose one: A. The mass of poisonous gases is tiny compared to the mass of Earth's atmosphere. B. The density of the HCN in the tail is so low that Earth does not absorb any of it. C. HCN reacts with oxygen in Earth's atmosphere to produce harmless compounds. D. Earth's magnetic field deflects all harmful gases away from the planet.
A. The mass of poisonous gases is tiny compared to the mass of Earth's atmosphere.
After it was discovered, astronomers predicted Uranus's orbit using Newton's laws of motion and gravity, which had worked extremely well for all of the other planets. To their surprise, they found that their observations of Uranus's motion through the sky did not match their predictions. Which of the following would be the most logical next step? Choose one: A. If the data doesn't match Newton's laws of motion and gravity, then the data must be bad, so this finding should be disregarded. B. Check for other previously undiscovered factors that might alter Uranus's orbit while still allowing it to obey Newton's laws of motion and gravity. C. Newton's laws of motion and gravity have been falsified, so they should be scrapped in favor of a completely new hypothesis. D. Newton's laws of motion and gravity must be modified to match the data.
B. Check for other previously undiscovered factors that might alter Uranus's orbit while still allowing it to obey Newton's laws of motion and gravity.
Why does Mars have such a low surface pressure? Visit the AstroTour "Atmospheres: Formation and Escape" on how planets gain and lose atmospheres. Choose the statement that corresponds to the biggest factor that resulted in Mars having a thinner atmosphere than Earth and Venus. Choose one: A. Mars is farther away from the Sun than Earth and Venus. B. Mars is less massive than Earth and Venus. C. Mars has a longer year than Earth and Venus. D. Mars had fewer comet impacts than Earth and Venus.
B. Mars is less massive than Earth and Venus.
Based on the law of conservation of angular momentum, what would happen to a collapsing cloud of gas and dust--isolated in space with no external forces--as its size decreases? Choose one: A. The cloud will gain mass. B. The cloud will spin faster. C. The cloud will spin more slowly. D. The cloud will lose mass. E. The cloud will not be able to collapse at all.
B. The cloud will spin faster.
Venus is hot and Mars is cold primarily because Choose one: A. the atmosphere of Venus is dominated by CO2, but the atmosphere of Mars is not. B. Venus has a much thicker atmosphere. C. Venus has stronger winds. D. Venus is closer to the Sun.
B. Venus has a much thicker atmosphere.
As a comet leaves the inner Solar System, its ion tail points Choose one: A. back along the orbit. B. away from the Sun. C. toward the Sun. D. forward along the orbit.
B. away from the Sun.
If a quantity is conserved, it means that it Choose one: A. changes only if an internal force acts. B. it doesn't change. C. can be saved for a later time. D. changes only if an external force acts.
B. it doesn't change
The terrestrial planets and the giant planets have different compositions because Choose one: A. the terrestrial planets have few moons. B. the terrestrial planets are closer to the Sun. C. the giant planets are mostly made of solids. D. the giant planets are much larger.
B. the terrestrial planets are closer to the Sun.
On rare occasions, comets have been seen orbiting the Sun. These are planetesimals made of rock and ice that become visible to us when their ice sublimates at the closest approach to the Sun, making them glow brightly and grow tails. Where do they come from? We can answer that question by studying the orbits of the comets that pass close enough to us that we can observe them. We see two distinct types of orbits: short-period and long-period comets. *Choose the answer below that most likely follows your observations* Choose one: A. Short-period comets come from a random direction in a spherical distribution around the Sun, and long-period comets come from farther away, in some location near the ecliptic plane of the Solar System. B. Both comet types come from some location near the ecliptic plane of the Solar System, but the long-period comets come from farther away. C. Short-period comets come from some location near the ecliptic plane of the Solar System, and long-period comets come from farther away, with random directions in a spherical distribution around the Sun. D. Both comet types come from random directions in a spherical distribution around the Sun, but the long-period comets come from farther away.
C. Short-period comets come from some location near the ecliptic plane of the Solar System, and long-period comets come from farther away, with random directions in a spherical distribution around the Sun.
Deep in the interiors of the giant planets, water is still a liquid even though the temperatures are tens of thousands of degrees above the boiling point of water. This can happen because Choose one: A. the outer Solar System is so cold. B. space has very low pressure. C. the pressure inside the giant planet is so high. D. the density inside the giant planet is so high.
C. the pressure inside the giant planet is so high.
Jupiter and Saturn, despite being considerably farther from us than the inner terrestrial planets, are very bright in our sky. Which of the following choices are possible explanations for this? Choose one or more: A. They are so hot that they emit blackbody radiation that peaks in the visible. B. Dust obscures our view of the inner planets more than the outer ones. C. Since they are closer to stars, more starlight is reflected off of them than the inner planets. D. They are larger than the terrestrial planets. E. They are more reflective (higher albedo) than most of the terrestrial planets.
D. They are larger than the terrestrial planets. E. They are more reflective (higher albedo) than most of the terrestrial planets.
A chunk of iron weighing a few kilograms flies into the inner Solar System, is captured by Earth's gravity, enters the atmosphere burning brightly, and lands on solid ground. Three different names apply to the different stages of its journey. Place them in order from first to last. - meteor - meteorite - meteoroid
*first stage* 1. meteoroid 2. meteor 3. meteorite *last stage*
Place in order of diameter the following types of extrasolar planets. (largest to smallest) - super-Earths - super-Jupiters - puffy Jupiters - mini-Neptunes
1. puffy Jupiters 2. super-Jupiters 3. mini-Neptunes 4. super-Earths
Asteroids are Choose one: A. small rock and metal objects orbiting the Sun. B. small icy objects orbiting the Sun. C. small icy bodies found only in the outer Solar System. D. small rock and metal objects found only between Mars and Jupiter.
A. small rock and metal objects orbiting the Sun.
Compare the atmospheric properties of the planets in the table to the right. The surface temperature is the average for the entire planet in units of Kelvin (subtract 273 from that number to convert it into units of Celsius). The surface pressure is related to how thick the atmosphere is (thicker atmospheres have more air molecules packed into the same volume, and thus higher pressure). Given the information in this table, how would you explain the difference in greenhouse effect strength for each of the planets? Choose one or more: A. Earth has a much higher percentage of nitrogen in its atmosphere, causing it to have a stronger greenhouse effect than Venus and Mars. B. Venus and Mars both have a very high percentage of carbon dioxide in their atmospheres, creating a stronger greenhouse effect than Earth's atmosphere, which has very little. C. Venus has a very strong greenhouse effect because it has a high percentage of carbon dioxide in its atmosphere and also a high surface pressure. D. Planets that are closer to the Sun will have a stronger greenhouse effect than those farther away from the Sun. E. Mars has a weak greenhouse effect because it has very low surface pressure.
C. Venus has a very strong greenhouse effect because it has a high percentage of carbon dioxide in its atmosphere and also a high surface pressure. E. Mars has a weak greenhouse effect because it has very low surface pressure.
Volcanoes on Enceladus affect the E Ring of Saturn by Choose one: A. dissipating the ring. B. stirring the ring particles. C. pushing the ring around. D. supplying ring particles.
D. supplying ring particles.
Put the following stages of planet formation in order of occurrence: • Clumps of dust collide and stick, forming planetesimals • Gas pushes smaller dust grains into larger grains • Km-sized planetesimals attract other objects by gravity • Planets of various sizes form • Larger dust grains grow into clumps
1. Gas pushes smaller dust grains into larger grains. 2. Larger dust grains grow into clumps. 3. Clumps of dust collide and stick, forming planetesimals. 4. Km-sized planetesimals attract other objects by gravity. 5. Planets of various sizes form.
Rank the following events earliest to lastest (order of planetary formation). • Secondary atmospheres form • Small bodies collide to form larger bodies • Primary atmospheres form • Gravity collapses a cloud of interstellar gas. • A rotating disk forms and dust grains stick together by static electricity • A stellar wind "turns on" and sweeps away gas and dust, removing primary atmospheres from planets
1. Gravity collapses a cloud of interstellar gas. 2. A rotating disk forms and dust grains stick together by static electricity. 3. Small bodies collide to form larger bodies. 4. Primary atmospheres form. 5. A stellar wind "turns on" and sweeps away gas and dust, removing primary atmospheres from planets. 6. Secondary atmospheres form.
All of Jupiter's moons experience tidal heating from Jupiter, and they show signs of recent geological activity because of it. Based on their appearance, rank the four Galilean moons in order from the most recently geologically active to the least. - Ganymede - Io - Callisto - Europa
1. Io 2. Europa 3. Ganymede 4. Callisto
The composition of the protoplanetary disk varies with distance from the protostar due to temperature. Starting with those closest to the protostar, place these materials in order based on where they can be found predominantly in their solid states. (Order of Planetary Formation) (closest to farthest) • water • Methane, ammonia, CO • Iron, silicates, carbon
1. Iron, silicates, carbon 2. Water 3. Methane, ammonia, CO
The AstroTour illustrates what the surface temperatures of Venus, Earth, and Mars would be without atmospheres, and it also shows the current value for each planet, with their actual atmospheres. Place the planets in order based on the discrepancy between their surface temperatures with and without their atmospheres. (least difference to most difference) • Earth • Venus • Mars
1. Mars 2. Earth 3. Venus
The distinct layers of Earth's atmosphere vary in temperature in a somewhat surprising way. Arrange these four layers in ascending order, based on the temperature at the upper boundary of each. (lowest temperature to highest temperature) • Stratosphere • Troposphere • Thermosphere • Mesosphere
1. Mesosphere 2. Troposphere 3. Stratosphere 4. Thermosphere
Place these volatiles in order of the temperatures at which each will condense to form a cloud layer on one of the four Jovian planets. (lowest to highest temperature) - Ammonia droplets - Methane ice - Water ice - Ammonium hydrosulfide ice - Ammonia ice
1. Methane ice 2. Ammonia ice 3. Ammonium hydrosulfide ice 4. Water ice 5. Ammonia droplets
Astronomers have determined that the gas giants are made mostly of hydrogen and helium. Given what you have learned about planetesimal formation through accretion, and the types of materials that condensed at certain distances from the Sun, which of the following is the most likely way that the gas giants formed? Choose one: A. Rock, metal, and ices made of materials such as water, ammonia, and methane, condensed into a solid and grew large enough to gravitationally attract hydrogen and helium gas from the Solar Nebula. B. Hydrogen and helium condensed into a solid and accreted to form the gas giants. C. Because hydrogen and helium could not condense into a solid at the temperature of the Solar Nebula, the gas giants must have formed elsewhere and been captured by the Sun's gravity.
A. Rock, metal, and ices made of materials such as water, ammonia, and methane, condensed into a solid and grew large enough to gravitationally attract hydrogen and helium gas from the Solar Nebula.
Comparing objects in a related group can reveal patterns among them. These patterns in turn can help us learn more about those objects than we could by studying each individually. With this goal in mind, watch this animation of the planets in the Solar System and select all of the following choices that describe the patterns that you've observed. As you do so, think about the implications of how the Solar System may have formed. Choose one or more: A. The orbits of the outer planets (those most distant from the Sun) are spaced farther apart from one another than the orbits of the inner planets. B. Planets orbit the Sun in random directions. C. All planets orbit the Sun in the same direction. D. The size of all planets increases with distance from the Sun. E. The orbits of the planets are evenly distributed in distance from the Sun. F. All planets orbit the Sun in a roughly flat plane. G. The closest planets to the Sun are much smaller than the planets that are farther away. H. All planets orbit the Sun in a spherical distribution.
A. The orbits of the outer planets (those most distant from the Sun) are spaced farther apart from one another than the orbits of the inner planets. C. All planets orbit the Sun in the same direction. F. All planets orbit the Sun in a roughly flat plane. G. The closest planets to the Sun are much smaller than the planets that are farther away.
Which of the following are characteristics of regular moons? Choose one or more: A. They have orbits that lie nearly in the equatorial planes of their planets. B. They revolve around their planets in the same direction as the planets rotate. C. They are much smaller than all of the known planets. D. They are usually tidally locked to their parent planets.
A. They have orbits that lie nearly in the equatorial planes of their planets. B. They revolve around their planets in the same direction as the planets rotate. D. They are usually tidally locked to their parent planets.
What was the evidence that indicated volcanic activity ended a billion years ago? Choose one: A. Astronomers analyzed the depth of the regolith (the layer of dust) on the surface of the Moon. B. Astronomers counted the number of craters for a given region on the surface. C. Astronomers analyzed some ice buried deep in a crater and detected microbes billions of years old, but nothing more recent. D. Astronomers counted the number of mare for a given region on the surface.
B. Astronomers counted the number of craters for a given region on the surface.
Remnants of volcanic activity on the asteroid Vesta indicate that members of the asteroid belt Choose one: A. were once part of a single protoplanet that was shattered by collisions. B. occasionally grow large enough to become differentiated and geologically active. C. used to be volcanic moons orbiting other planets. D. have all undergone significant chemical evolution since formation.
B. occasionally grow large enough to become differentiated and geologically active.
At least 75% of asteroids are primordial C-type. What does this imply about how the asteroid belt was formed? Choose one: A. It was formed entirely of the pieces of a shattered planet. B. It was formed mostly from pieces of objects that were large enough to differentiate and were later shattered, but it also contains some planetesimals that were prevented from getting large enough to differentiate. C. It was formed entirely of pieces of planetesimals that were prevented from getting large enough to differentiate, and thus were never part of a planet. D. It was formed mostly from pieces of planetesimals that were prevented from getting large enough to differentiate, but it also contains some pieces of objects that were large enough to differentiate and were later shattered.
D. It was formed mostly from pieces of planetesimals that were prevented from getting large enough to differentiate, but it also contains some pieces of objects that were large enough to differentiate and were later shattered.
What is the most likely reason for the different levels of geological activity between the Galilean moons? Choose one: A. Larger moons will have more geological activity than smaller ones. B. Each moon is randomly unique in its properties. C. The composition of the moons is different. D. Moons farther away from Jupiter experience weaker tidal heating.
D. Moons farther away from Jupiter experience weaker tidal heating.
Due to the mutual synchronous rotation of Pluto and Charon, choose the statement below that best describes what an observer on Pluto would see when looking toward Charon. Choose one: A. The observer would always see the same side of Charon, which would make circles around a point in the sky but never rise or set below the horizon. B. The observer would always see the same side of Charon, which would rise and set as it orbits Pluto. C. The observer would see different sides of Charon as it rotates on its axis and would see it rise and set as it orbits Pluto. D. The observer would always see the same side of Charon, which would appear to hang motionlessly in the same spot in the sky all the time.
D. The observer would always see the same side of Charon, which would appear to hang motionlessly in the same spot in the sky all the time.
How do astronomers measure the size of the Great Red Spot? Choose one: A. They send spacecraft to the top of the spot to physically measure the size of it. B. They use the Doppler shift in reflected light from the cloud tops. C. They time the spot as it makes a rotation around the planet. D. They compare its dimensions to the known diameter of Jupiter.
D. They compare its dimensions to the known diameter of Jupiter.
Impacts on the terrestrial worlds Choose one: A. periodically become more common and then are less common for a while. B. have occurred at approximately the same rate since the formation of the Solar System. C. never occur any more. D. are less common than they used to be. E. are more common than they used to be.
D. are less common than they used to be.
Io has the most volcanic activity in the Solar System because Choose one: A. it is continually being bombarded by material from Saturn's E Ring. B. of gravitational friction caused by the moon Enceladus. C. it is one of the largest moons and its interior is heated by radioactive decay. D. its interior is tidally heated as it orbits Jupiter. E. the ice on the surface creates tremendous pressure on the water below.
D. its interior is tidally heated as it orbits Jupiter.
Zonal winds on the giant planets are stronger than those on the terrestrial planets because Choose one: A. the giant planets have more thermal energy. B. the moons of a giant planet feed energy to their planet through the magnetosphere. C. the moons of the giant planets provide additional pull. D. the giant planets rotate faster.
D. the giant planets rotate faster.
In this video, angular momentum is only approximately conserved. This is because Choose one: A. the measurement of angular momentum depends on your reference frame. B. the person on the platform is exerting a force when she pulls her arms in and pushes them out. C. no quantities are ever really conserved. D. there are small external forces acting—friction and air resistance, for example.
D. there are small external forces acting—friction and air resistance, for example.
If you wanted to search for faint rings around a giant planet by sending a spacecraft on a flyby, it would be best to make your observations Choose one: A. as the spacecraft approached the planet. B. while orbiting the planet. C. while orbiting one of its moons. D. during the closest flyby. E. after the spacecraft passed the planet.
E. after the spacecraft passed the planet.
Earth's interior is heated by Choose one: A. gravity and tidal effects. B. radioactive decay and gravity. C. angular momentum and gravity. D. angular momentum and tidal effects. E. radioactive decay and tidal effects.
E. radioactive decay and tidal effects.
