ASTRO 150 Final quizzes

What is the most likely way that pieces of asteroids end up on the surface of Earth? a. Large impacts break pieces off and send them hurtling toward Earth b. Impacts disrupt the asteroids. Interactions with Jupiter send the pieces to Earth c. Pieces of asteroids never land on Earth d. We actually have no idea how this happens

b

What is the origin of the cratering population of the outer Solar System? a. Rocky bodies from the Asteroid Belt b. Icy bodies from the Kuiper Belt c. Icy bodies from the Oort Cloud d. Rocky bodies flung to the outer Solar System by the Jupiter

b

Which of the following has not contributed to the depletion of Mars' atmosphere? a. Solar stripping b. Fast rotation c. Large impacts d. Low surface gravity

b

Why are the surfaces of worlds in the outer Solar System made mostly of ice? a. Rock and iron do not exist outside of the Snow Line. b. Ice is more abundant than rock and iron outside of the Snow Line c. Only ices can form outside of the Snow Line. d. All of the rocky bodies accreted to form the planets, leaving only icy bodies behind

b

An exoplanet with a mass 10 times that of Jupiter would have a size (radius) a. 10 times larger than Jupiter b. 10 times smaller than Jupiter c. about the same as Jupiter d. that is just about any value

c

Asteroids larger that 500 km are spherical because a. they are made of mechanically weak materials b. they were spinning fast when they formed which shaped them into a sphere. c. their central pressure is greater than the strength of rocks d. they suffered numerous impacts that circularized their shape

c

If a planet formed well inside of the orbit of Mercury, what would be its most likely composition? a. Hydrogen b. Methane Ice c. Iron d. Rock

c

In the figure above, again pretend that the yellow object is a star with the same mass as the Sun and the blue object is a planet orbiting this star. The blue planet is located at 3 AU from the star. What is the blue planet's approximate orbital period in years? a. 2.8 b. 3.4 c. 5.2 d. 9.0

c

All of the giant planets are generating more energy in their interiors than is expected. The energy generation mechanism is a. gravitational contraction b. radioactive decay c. nuclear fusion d. tidal kneading

a

Asteroids in a 2:1 resonance with Jupiter a. have their orbits changed dramatically. b. are kicked out, but are constantly replenished by Trojan Asteroids c. are too large for Jupiter to change their orbits d. remain in the Asteroid Belt because Jupiter keeps 'missing' them.

a

Astronomers estimate that there may be as many as a trillion cometary objects (KBOs) in the Kuiper Belt. Despite their large numbers, the majority of known KBOs have only been discovered in the last decade. Why is this? a. Most KBOs are small and have very low albedos so they are hard to detect b. Most KBOs travel too close to the Sun to be detected c. It has taken many years for spacecraft to reach the Kuiper Belt to take images of these objects d. Most KBOs are bright and icy, but they are moving too fast to be detected

a

Geologic activity on the surface of asteroids a. occurred long ago b. ended yesterday c. is ongoing d. never occurred

a

How did pieces of Vesta (the parent body of Achondrites) end up on Earth? a. They occasionally wander into resonance with Jupiter and are ejected from the Asteroid Belt. b. They constantly collide with larger bodeis that send them toward Earth. c. Resonances with Mars pushes them toward the Earth d. Large impacts on Vesta's surface eject them from the Asteroid Belt

a

If geologic activity scales with size, why do small satellites (smaller than the Moon) like Ariel and Titania show signs of very recent geologic activity and the Moon does not? a. Their surfaces are different composition than the Moon b. Their moment of inertia is different than the Moon c. They are heavily cratered and are actually rubble piles d. They have larger rocky cores than the Moon so geologic activity can last longer.

a

If you could drag Jupiter to within Mercury's orbit (very close to the Sun), what would happen to it? a. It would get hotter, but that's about it b. It would completely lose it's atmosphere via thermal escape c. It would lose a significant fraction of it's atmosphere via thermal escape d. It would turn into a rocky, terrestrial-like planet

a

Io's orbit is in 2:1 resonance with the orbit of Europa and in 4:1 resonance with the orbit of Ganymede. The period of Io's orbit is 1.8 days. What then, must be the orbital periods of Europa and Ganymede? a. Europa = 3.6 days and Ganymede = 7.2 days b. Europa = 36 days and Ganymede = 72 days c. Europa = 7.2 days and Ganymede = 3.6 days d. Europa = 28 days and Ganymede = 72 days

a

Jupiter takes 12 years to orbit the Sun. An asteroid in a 4:1 resonance with Jupiter would take how many years to orbit the Sun? a. 3 years b. 4 years c. 12 years d. 48 years

a

Long period comets come from a. the Oort Cloud b. the Kuiper Belt c. the Asteroid Belt d. Saturn's rings

a

Neptune's moon, Triton, has active volcanoes on the surface. The most probable energy source for these volcanoes is a. the Sun b. tidal heating c. the radioactive decay of elements in Triton's interior d. giant impact cratering

a

No asteroid rotates faster than a few hours. Why is this? a. Most asteroids are not solid objects. If they rotate faster they would fly apart. b. All asteroids rotate at these speeds when they form c. Most asteroids are not big enough to rotate very fast d. Asteroids are made of weak materials. They would break into pieces if they rotated faster

a

Saturn has a satellite that you have not yet learned about, called Enceladus. Enceladus is just a little over 500km in diameter. What shape do you expect Enceladus to be a. Spherical b. Oblate c. Potato-shaped d. Not enough information - its shape depends on its composition

a

The Widmanstatten pattern found in iron meteorites forms under what conditions? a. Slow cooling and high pressure b. Large impacts that shatter the parent body c. Exposure to radioactive elements d. Rapid cooling at very low pressures

a

The color in the clouds of giant planet atmospheres is due mainly to a. trace gasses present in their atmospheres b. Hydrogen and Helium in their atmospheres c. strong interactions with their magnetic fields d. material magnetically stripped from their satellite surfaces

a

The composition of the satellites of the giant planets is best described as a. primarily ice with a little rock b. primarily rock with a little ice c. mostly rock d. a mix of iron and ice

a

The orbits of the irregular satellites of the giant planets are all high eccentricity. What does the term eccentricity mean? a. Their orbits are non-circular. b. Their orbits are nearly circular c. They orbit in the opposite direction to the spin of the planet. d. Their orbits are completely random

a

The regular satellites of the giant planets formed via the process of a.Co-Accretion b. Capture c. Giant Impact d. Fission

a

The total amount mass contained in Saturn's rings is equivalent in mass to a. a small asteroid b. the Earth's Moon c. all of Saturn's satellites combined d. Mercury

a

What type of parent body must Carbonaceous Chondrite meteorites come from? a. A small, undifferentiated object b. A large, differentiated object c. A small, slightly differentiated object d. It could come from any of the objects listed above

a

Why do satellites not form within the Roche Limit of a planet? a. Particles are pulled apart by the extreme tidal forces close to the planet. b. There isn't enough material to form a moon near the giant planets c. Moons do form within the Roche Limit but migrate out to their current positions over time. d. The moons are icy and they can't form next to hot objects like the giant planets.

a

Carbonaceous Chondrite meteorites all contain chondrules. What are chondrules? a. Liquid water trapped in bubbles beneath the surface of the meteorite b. Carbon-rich spherical matrices c. Small spheres of amino acids d. Micro-meteorite impact craters on the meteorite's surface

b

Compared to the surfaces of asteroids, the surfaces of Kuiper Belt Objects are a. lacking in volatile materials b. much more volatile rich c. much brighter d. more heavily cratered

b

Crater counting the surfaces of the outer Solar System satellites yields a. absolute ages for these worlds. b. relative ages for these worlds c. no useful information for these worlds d. ages older than any we have found in the inner Solar System

b

Halley's comet takes about 75 years to orbit the Sun. Why do we believe that Haley's comet was not on its present course 4 billion years ago? a. Halley's comet is too large to have a stable orbit for 4 Byrs b. It would have completely disintegrated if had been in this orbit for 4 Byrs c. Jupiter would have kicked it out to the Oort Cloud by now d. Comets could not have formed as early as 4 Byrs ago

b

How do we know that the Solar System is 4.5 Byrs old? a. Most samples from the lunar surface are 4.5 Byrs old b. Carbonaceous Chondrites are 4.5 Byrs old c. Martian meteorites are 4.5 Byrs old d. The oldest Earth rocks are 4.5 Byrs old

b

In sections, you learned about a common characteristic of exoplanets discovered by the radial velocity method. What was it? a. The planets are generally very small and orbit very far from their parent star b. The planets are generally very large and orbit very close to their parent star c. The planets are generally very large and orbit very far from their parent star d. The planets are generally very small and orbit very close to their parent star

b

In the figure above, pretend that the yellow object is a star with the same mass as our Sun. The blue object is a planet orbiting this star. You determine the planet's orbital period to be 4 years. Approximately how far (ie. its semi-major axis) from the star is this planet (in AU)? a. 2.0 b. 2.5 c. 3.5 d. 16

b

In the original model for the formation of planets by accretion, one of the main problems is that the formation of Neptune a. is hindered by resonances with Jupiter b. takes longer than the age of the Solar System c. happens too quickly where it is located d. results in a planet that is too large

b

Mars no longer has a magnetic field. Why (what is it lacking)? a. An electrically conducting material (like iron). b. An internal heat source to liquify the conducting material c. A moderately fast rotation d. It's lacking all of the above properties

b

Neptune's satellite, Triton, looks like a common "regular" giant planet satellite, but you learned that it is actually an irregular satellite. Which of the following is one of the reasons we suspect that Triton is not a regular satellite? a. It has very short orbital period compared to other satellites. b. It is in a retrograde orbit c. It is geologically active d. It is synchronously locked to Neptune

b

Stony meteorites have a density of about ________ g/cm3. a. 1 b. 3 c. 5 d. 8

b

The surface composition of all of the worlds of the outer Solar System is predominantly a. methane ice b. water ice c. dry ice (carbon dioxide ice) d. a combination of rock and water ice

b

The surfaces of the satellites of the giant planets are crater saturated. What does saturation mean in this context? a. Liquid water trapped beneath the surface oozes out after large impacts. b. The destruction of old craters happens as fast as new ones form c. Ice melts and fills the basins of the impact craters on icy satellites d. The filling in of craters on a surface by lava flows

b

Venus no longer has a strong magnetic field. Why (what is it lacking)? a. It does not have a conducting core. b. It does not rotate fast c. It has no internal heat source d. It does not have prograde rotation

b

What is the Snow Line? a. The distance from the Sun where it can snow on a world with an atmosphere b. The distance from the Sun where Rocks, Iron and Ices can condense c. The distance from the Sun where Rocks, Iron and Ices can flow like a liquid. d. The distance from the Sun where icy polar caps can form on a world

b

Why does the methane in Titan's atmosphere need a constant source? a. Methane is radioactive and decays to a more stable element. b. Methane strongly interacts with the sun and is easily broken apart c. Methane bonds easily to nitrogen which makes new compounds in the atmosphere d. Ammonia and methane combine easily to create hydrocarbons

b

Why is Io the only solid surface in the Solar system that is completely devoid of impact craters? a. Jupiter's gravity deflects most impactors from Io's surface b. The surface is constantly being resurfaced, covering all impact craters c. The surface is completely molten so impactors disappear like pebbles thrown into a pond. d. Io is too far from the Sun to get hit by impactors

b

In what way are the giant planets Jupiter and Saturn more like stars than terrestrial planets? a. Like stars, Jupiter and Saturn have atmospheric storms b. Unlike any terrestrial planets, Jupiter and Saturn have magnetic fields that are generated in their interiors c. Like stars, Jupiter and Saturn are big balls of gas composed primarily of Hydrogen and Helium d. Unlike terrestrial planets, Jupiter and Saturn are impacted by comets

c

Jupiter's regular satellites, Io and Europa, are geologically active today because their interiors are heated by a. gravitational contraction of their interiors b. radioactive decay of elements in their cores c. gravitational interactions with Jupiter and its other satellites d. high energy particles from the Sun

c

Jupiter's rings are not like Saturn's rings. Which statement best describes our reasons for believing that Jupiter's rings formed through a different process than Saturn's rings? a. They exist outside of Jupiter's Roche Limit. b. They are made primarily of water ice. c. They are much smaller and darker than typical ring particles d. They orbit at high inclination, unlike other ring systems

c

Nearly 50% of the mass of the Asteroid Belt a. is contained in a single asteroid b. is found in the Trojan asteroid groups c. is contained in about four large asteroids d. is in resonance with Jupiter

c

The Hyugen's probe detected a spike in methane as it touched down on a solid surface on Titan. What did this imply about the area in which the probe landed? a. It landed near the source of the atmospheric methane b. It actually landed in a methane lake, not on a solid surface. c. It landed at low tide d. It landed on a the shore of a lake

c

The abundance of Ices in the Solar System a. is very low compared to metal abundances. b. is about the same as metal abundances c. is much higher than the abundance of metals d. The abundances are so low that there is no comparing them to metals

c

The belts and zones of circulation evident in Jupiter's atmosphere are a consequence of a. strong tidal forces b. strong magnetic field generation c. rapid rotation d. atmospheric composition

c

The gaps in Saturn's rings are caused by a. resonances with Jupiter changing the ring particles orbits b. large satellites accreting the material from within those regions c. resonances with Saturn's satellites changing the ring particles orbits d. large impacts on small moons within the gaps that clear out the particles

c

Why do we think the water on Earth had to come from the outer Solar System? a. Water is not dense enough to form in the inner Solar System b. Comets do not come into the inner Solar System c. Water can not exist as a solid inside of the Snow Line d. Water molecules can easily escape the Earth's atmosphere

c

Why does the core of a giant planet have to form quickly (in ~10 Myrs or less)? a. All available material will be quickly accreted by other objects in the vicinity b. Available material outside the snow line will evaporate before it has a chance to form the core c. Available material will be blown out of the vicinity when the Sun "turns on" d. Available material will be quickly ejected from the area by resonances with other objects

c

Why is it unlikely that Saturn's volcanically active moon, Enceladus, is being powered by tidal heating? a. Enceladus is way too small to be tidally heated b. Enceladus is heated by radioactive decay of K, Th and U. c. Enceladus is not in resonance with any other satellites d. Enceladus lacks a rocky core to power tidal heating

c

You find a meteorite with a density of 7.5 g/cm3. Which type is your meteorite? a. Carbonaceous Chondrite b. Achondrite c. Stony-Iron d. Iron

c

You now understand a great deal more about tidal forces than when we first encountered them while discussing the Earth's Moon. Recall that I said that the tidal force on the Earth due to the Moon is twice that of the tidal force on Earth due to the Sun. How can this be when the Sun is much, much more massive than the Earth's Moon? a. The Moon has a higher density than the Sun. b. The Moon rotates on its axis much faster than the Sun c. The Moon is much closer to the Earth than the Sun d. The Earth is more massive than the Sun

c

Atoms in the Solar System heavier than Iron (Fe) are created during a. the Big Bang b. star formation c. stellar nucleosynthesis d. supernovae explosions

d

How do we know that the Asteroid Belt was not from a single planet that was shattered by some catastrophic event? a. There is too much material in the Asteroid Belt to form just one planet b. We have been unable to find the impactor that shattered the planet c. The pieces of the shattered planet would not have remained in a belt around the Sun d. We found carbonaceous chondrite meteorites on Earth

d

Late Heavy Bombardment was triggered by a. resonances between Neptune and the Kuiper Belt b. resonances between Jupiter and the Asteroid Belt c. Uranus' and Neptune's formation far outside of the Snow Line d. Jupiter's migration and resulting 1:2 resonance with Saturn

d

Most asteroids are a. very young b. geologically active. c. large and spherical d. small and irregular shaped

d

Nitrogen and methane are the main constituents of Titan's atmosphere. Titan's atmosphere is opaque to visible light, but nitrogen and methane are colorless gasses. Why can't we see the surface of Titan in visible wavelengths? a. Trace amounts of ammonia create a smog layer b. Nitrogen reacts strongly with ammonia to produce smog c. Photodissociation of water produces smog d. Photodissociation of methane produces smog

d

Regular satellites of the giant planets all have prograde orbits. What does prograde mean? a. Their orbits are inclined to the equator of the planet b. Their orbits are highly eccentric c. Their orbits are nearly circular d. They orbit in the same direction the planet spins

d

Six billion years from now the Earth will likely be a. a little warmer than it is today b. kicked out of the Solar System as Jupiter continues to migrate toward the Sun c. sucked into the black hole that was the Sun d. engulfed by the dying Sun

d

The Kuiper Belt is a disk of icy material that a. was once one large object, but was disrupted/destroyed by a giant impact b. orbits in a sphere many thousands of AU from the Sun c. was flung to the outer Solar System by Jupiter d. has not had time to accrete into a single object

d

The Roche Limit for Saturn is about 2.5 planetary radii away from the center of the planet. This distance is a. near the inner edge of the rings b. within the largest gap in the rings c. just beyond the outermost satellite of Saturn's system d. near the outer edge of the rings

d

The Snow Line is located at ~3 AU from the Sun. At what distance would you most likely find Carbonaceous Chondrite parent bodies in the Asteroid Belt? a. 1 AU b. 2 AU c. 3 AU d. 4 AU

d

The surface of Saturn's moon, Rhea, is about 4 Byrs old because it has a crater density that is similar to the crater density of the lunar highlands. Why might this statement be completely wrong? a. Rhea is smaller than the Moon so there is no way it can have the same crater density b. Rhea is a protected by a larger planet (Saturn), which deflects many impactors. c. Crater density has absolutely no relation to the age of a satellite's surface d. Rhea may not have been hit by the same population of impactors as the Moon

d

What do meteorites tell us about the Asteroid Belt? a. It is composed of mostly objects covered in basalt b. It is composed of mostly large objects c. It is composed of mostly icy objects d. It is composed of mostly small objects

d

What is unusual about the position of Uranus and Neptune in the Nice Model of Solar System formation? a. They formed in another system and were captured by the Sun b. They formed at a much farther distance and migrated in to their present positions c. They formed at their present positions but their order is reversed d. They formed at a much closer distance and were kicked out to their present positions

d

Which of the following is not necessary for planetary magnetic field generation? a. Electrically conducting material in the core b. Internal source of energy (heating) c. Moderately fast rotation d. Rocky mantle material

d

Which of the following was probably not Jupiter's fault? a. The impact of the Earth by a 10 km asteroid 65 Myrs ago b. The volcanoes on Io c. The structure of the Asteroid Belt d. The retrograde orbit of Triton

d

You find an asteroid in the Asteroid Belt that is highly differentiated. Which type of meteorite could not have come from this asteroid? a. Achondrite b. Stony-Iron c. Iron d. Carbonaceous Chondrite

d