Origin of the Solar System & Exrasolar Planets
According to the solar nebula theory, which of the following is true?
According to the theory, planets form from the gases surrounding a star after it forms.
How did the solar nebula get cleared of material?
All of these choices are correct.
How does the solar nebula theory account for the drastic differences between Terrestrial and Jovian planets?
All of these choices are correct.
How is the solar nebula theory supported by the motion of solar system bodies?
All of these choices are correct.
What evidence can you cite that disks of gas are common around young stars?
All of these choices are correct.
What evidence can you cite that planets orbit other stars?
All of these choices are correct.
What evidence do we have that planets form along with other stars?
All of these choices are correct.
Which is the process that cleared the solar nebula away and ended planet building?
All of these choices are correct.
Which properties of the solar system are accounted for in this simple series of three diagrams depicting the solar nebula hypothesis?
All of these choices are correct.
Why would you expect the process of the separation of material in a planet to occur?
All of these choices are correct.
Which was an objection to the passing star hypothesis?
All of these were objections.
Which sentence(s) below is(are) correct? Planets that form at the highest temperature are ________ the sun and are made of ________.
Both "closest to; metals and their oxides" and "farthest from; ammonia, water, and methane" are correct.
How do asteroids and comets differ
Comets contain ices.
What is the difference between the processes of condensation and accretion?
Condensation is the building of larger particles one atom (or molecule) at a time, whereas accretion is the sticking together of larger particles.
Based on how planets form, select all of the correct statements from the following list
Due to higher temperatures, planets forming close to the sun could only include rocks and metals.A heavily cratered surface is an old surface.Farther from the sun, ices could collect on the rocky, metallic cores.Exactly how planets differentiated is not completely clear.
Which of the following accurately describes the differentiation process?
High-density materials sink toward the center and low-density materials rise toward the surface of a molten body.
How do you think the age of another planetary system would compare to the age of our solar system?
It could be any of these.
How do you think the age of another planetary system would compare to the age of our solar system? What is the evidence for this?
It could be any of these: our solar system is about halfway through its evolution, and our sun is probably a second- or third-generation star.
What indicates that this planet formed far from the sun?
It has rings and therefore must be massive, and massive planets form far from the sun.
Why do astronomers assume the surface of the planet in the figure is old?
It is covered with craters.
What produced the helium in the sun's atmosphere?
It was among the gases from which it formed.
What produced the helium in Jupiter's atmosphere?
It was captured directly from the solar nebula.
Which one of the Jovian planets is largest?
Jupiter
According to the solar nebula theory, why are Jupiter and Saturn much more massive than Uranus and Neptune?
Jupiter and Saturn formed earlier and captured nebular gas before it was cleared out.
How does the solar nebula theory explain the formation of an asteroid belt between Mars and Jupiter rather than a planet at this location?
Jupiter formed early and its gravitational influence altered the orbits of nearby accreting planetesimals such that their collisions became destructive rather than constructive.
Which one of the following groups of objects is farthest from the sun?
Kuiper belt
Why do we reject the formation of planets as proposed by Buffon (the passing star hypothesis)?
Material pulled out of the sun would be too hot to condense and planetary systems are common, whereas near star collisions are rare.
Which planet is shown the figure?
Mercury
Which list below ranks the Terrestrial planets in order of increasing size, from left to right?
Mercury, Mars, Venus, Earth
Rank the Terrestrial planets in order of distance from the sun, closest to farthest, from left to right.
Mercury, Venus, Earth, Mars
Based on the properties of the solar system that any formation theory must explain, select all of the correct statements from the following list.
Meteoroids are objects that fall to planets. Most of the objects in the solar system fit into a giant disk. Planets like Earth have few or no moons and no rings.
Based on the discovery of planets orbiting other stars, select all of the correct statements from the following list.
Most extrasolar planets discovered so far are massive Jupiter-like planets Doppler shifts in the spectrum and variations in the brightness of a star can both be used to detect unseen planets in orbit. Most exoplanets are not detected by direct observation. Disks of hot gas and dust from which planets could form have been observed.
Planet Composition. What composition might you expect for a planet that formed in a region of the solar nebula where the temperature was about 100 K? Choose the best answer.
NOT Metals or Ices
Which one of the Jovian planets is farthest from the sun?
Neptune
Based on theories of Earth's origin, select all of the correct statements from the following list.
Our solar system is believed to have formed from a disk of gas and dust. An early theory of solar system origin was catastrophic. An early theory of solar system origin was evolutionary. The sun and the solar system must have formed from the remains of earlier generations of stars.
Why haven't we detected low-mass planets close to their stars and high-mass planets far from their stars?
Our techniques are not yet sensitive enough and we have not been observing for a long enough time.
According to the solar nebula hypothesis, which of the following is true?
Planetary systems should be common.
Which planet is shown in the figure?
Saturn
Which planets are more dense?
Terrestrial planets
Which was an objection to the nebular hypothesis?
The angular momentum problem.
What is the origin of the atoms of hydrogen, oxygen, and sodium in the perspiration that exits your body during an astronomy exam?
The hydrogen nuclei were produced a few minutes after the big bang event 13.7 billion years ago, and the oxygen and sodium nuclei were synthesized inside stars more than 4.6 billion years ago.
What was the major problem for the solar nebula hypothesis that was proposed by Pierre-Simon de Laplace?
The sun contains little of the angular momentum of the solar system.
Why are there so many cratered surfaces in the solar system?
There was much debris left over from the formation of the planets and moons, and many collisions in the early solar system.
What are the general characteristics of the extrasolar planets discovered so far?
They have high mass and orbit close to their stars.
Compare the two radial velocity curves shown here for the stars 51 Pegasi and Upsilon Andromedae. Why is the curve for Upsilon Andromedae more complex than that of 51 Pegasi?
Upsilon Andromedae has more than one planet.
How do we know that extrasolar planets are orbiting other stars?
We see a star's light dim as a planet passes in front of the star and detect alternating Doppler shifts in the spectra of some stars.
If you visited another solar system in the act of planetary formation, would you expect to see the condensation sequence at work?
Yes, since it is based on temperature and therefore on distance from the star.
Is there any evidence for what the solar nebula theory suggests?
Yes; disks of gas and dust and actual planets have been discovered orbiting other stars.
Which kind of planet has rings?
a Jovian planet
Which is in the early stages of planet formation?
a cold dust or debris disk
Solid particles sticking together is called which of the following?
accretion
How old do astronomers think the solar system is?
almost 5 billion years old
Where are most asteroids located?
between the orbits of Mars and Jupiter
Particles growing by adding matter from surrounding gas is called which of the following?
condensation
When did the majority of the craters on the planet in the figure form?
early in the history of the solar system, when there was more debris for collisions
What composition might we expect for a planet that formed in a region of the solar nebula where the temperature was about 1,050 K?
feldspars
How do astronomers estimate the age of the solar system?
from radioactive dating
What are most craters in the solar system caused by?
impacts from space
Where are craters found?
most solid surfaces in the solar system
According to the condensation sequence, which substance would condense out of the solar nebula first?
nickel
What produced the helium in the sun's core?
nuclear fusion
What produced the iron in Earth's core?
some nuclear fusion in a massive star's core, spread to interstellar space via supernovae explosions
What produced the gold and silver in Earth's crust?
supernovae
In the table shown, which object's observed density differs least from its uncompressed density?
the moon
According to which theory should the sun's equator be nearly in the plane of Earth's orbit?
the solar nebula hypothesis
