1) Long period comets are thought to reside mainly in the 1) A) Interstellar Medium. B) asteroid belt. C) Oort Cloud. D) Kirkwood gaps. E) Kuiper Belt. 2) Pluto is most similar to 2) A) Mercury. B) Triton. C) Europa. D) Miranda. E) our Moon. 3) What might have made the original solar nebula begin to contract? 3) A) the shock wave from a nearby exploding star B) interstellar magnetism generated by pulsars C) the Big Bang D) the formation of our arm of the Milky Way E) the large amount of angular momentum in the nebula 4) The first hint of the role of asteroids in extinction of the dinosaurs came from 4) A) finding dinosaur fossils with meteorites imbedded in them. B) finding the huge crater in the Yucatan. C) finding that no volcanic eruptions were linked to their disappearance. D) finding a layer of worldwide iridium enriched dust. E) finding that dinosaurs were warm-blooded and smart. 5) Why did a major planet not form out in the Kuiper Belt? 5) A) Sedna disrupted the objects closer in to the Sun. B) Comets bombarded these bodies violently, breaking them apart. C) Some may have, but they have since migrated to orbits nearer the Sun. D) It was not in the ecliptic like the planets; there was no material out there. E) One did, and its name is Pluto. 6) On its way to Jupiter, Galileo also gave us close-ups of 6) A) Mercury and Venus. B) Gaspra and Ida. C) Ceres and Vesta. D) Mathilde and Eros. E) Mars and Venus. 7) As the terrestrial protoplanets grew in size, their strengthening gravitational fields produced many high-speed collisions between planetsimals and protoplanets which led to what process? 7) A) collision B) condensation C) fragmentation D) core-accretion E) differentiation 8) What is the role of irregularities in the solar system in terms of theories of its origin? 8) - 1 -
A) They are too minor to play a role; astronomers ignore them. B) The solar system has no irregularities; it is perfectly regular and orderly. C) They introduce a need for flexibility in theories of the solar system's origin. D) Theories of the solar system are entirely based on the many irregularities found among the planets and moons. E) The solar system is chaotic, with irregularities the rule. 9) The Oort Cloud is thought to be 9) A) a cloud of debris that occasionally encounters the Earth, causing a meteor shower. B) a cloud of asteroids moving between the orbits of Mars and Jupiter. C) the material in the ecliptic plane that creates the zodiacal light. D) the spherical cloud of comets and some larger icy bodies surrounding the outer solar system. E) the cloud of gas and dust from which our solar system formed. 10) What is a distinguishing characteristic of planetesimals which was critical to planetary formation? 10) A) They were large enough so that their gravity could attract more material and grow still larger. B) They started as round balls, and grew from there. C) They were the results of fragmentation. D) They are the final stage in planetary formation, before the accretion of gas. E) They were "sticky" enough to hold clumps of matter they encountered. 11) Carbonaceous Chondrites are believed to come from 11) A) a broken up cometary nucleus, dark like Comet Halley's nucleus. B) coal formed on Mars, then blown into space by asteroid impacts. C) the crust of a differentiated C type asteroid, now broken up. D) the core of a differentiated type M asteroid, now broken up. E) deep space, far beyond the solar system, hence their very low density. 12) Pluto's bulk density is: 12) A) 700 kg/, like Saturn a mix of hydrogen and helium slush. B) 2,100 kg/, similar to Callisto's mix of rock and ice. C) 400 kg/, like Comet Halley's nucleus, a ice ball with many gas pockets. D) 3,400 kg/, comparable to our Moon's. E) 1,200 kg/, like Mimas, made of almost pure ice. 13) Conservation of angular momentum means that a spinning body tends to 13) A) keep spinning. B) fly apart. C) gravitationally collapse. D) slow down. E) wobble into an eccentric orbit. 14) Planetary orbits 14) A) have the Sun at their exact center. B) are evenly spaced throughout the solar system. C) are spaced more closely together as they get further from the Sun. D) are highly inclined to the ecliptic. - 2 -
E) are almost circular, with low eccentricities. 15) According to the Solar Nebula theory, planets 15) A) should be randomly oriented to their star's equator. B) will revolve opposite the star's rotation. C) should be a common result of star formation. D) should be extremely rare. E) should orbit perpendicular to their star's equator. 16) Which of these is not a characteristic of the solar nebula theory? 16) A) All the planets should follow the ecliptic plane. B) Larger planets should form closer to their star, where there is more debris. C) Planets should rotate counterclockwise as well. D) All the planets should orbit the sun counterclockwise. E) The ecliptic is the equator for the Sun. 17) The NASA orbiter that ultimately landed on the surface of the asteroid Eros was 17) A) New Horizons. B) Clementine. C) Stardust. D) Giotto. E) NEAR Shoemaker. 18) Before it arrived in orbit about Eros, the NEAR spacecraft also flew past 18) A) Comet Halley. B) Comet Wild. C) Mars. D) asteroid Mathilde. E) Venus. 19) A successful theory of the formation of the solar system must explain 19) A) that all planets have elliptical orbits with high eccentricities. B) the existence of the asteroid belt between Jupiter and Neptune. C) that the inner planets have more hydrogen and helium in their atmospheres than do the outer planets. D) that all planets rotate in a prograde sense. E) all observed properties of the solar system. 20) In comparing our own solar system with others found to date, we find: 20) A) hot Jupiters, even closer to their stars than Mercury is to our Sun. B) jovians often lie much closer to their suns than ours do. C) that most orbits are less circular than planets around our Sun. D) multiple planets are found in some systems. E) all of the above 21) The type of asteroid that would be the densest would be type 21) A) M. B) V. C) Z. D) C. E) S. 22) Pluto's density is most similar to 22) A) Mercury, but nor Venus, Earth, or Mars. - 3 -
B) the terrestrial planets. C) moons of the jovian planets. D) the jovian planets. E) Saturn, but not Jupiter, Uranus, or Neptune. 23) The Trojan asteroids have orbits that 23) A) cross the orbit of Earth at perihelion. B) cross the orbit of Mars, but not Earth, at perihelion. C) stay out beyond Neptune. D) are, on average, closer to the Sun than we are. E) stay sixty degrees ahead of or behind Jupiter. 24) What phase of planet formation caused the jovian planets to form? 24) A) core-accretion B) collision C) condensation D) fragmentation E) differentiation 25) In terms of composition 25) A) the terrestrials are similar to the sun, for they formed closer to it. B) the jovians are much more like the sun than the terrestrials are. C) each planet is unique, with no similarities among them. D) the sun is unique in having far more light elements than any of the planets do. E) all the planets are made of the same elements, and in the same proportions. 26) The most famous asteroid impact scar on Earth is located in 26) A) Antarctica. B) Florida. C) northern Canada. D) northern Yucatan. E) Arizona. 27) What factor caused different planets to form out of different types of material? 27) A) The quantity of dust particles in the solar nebula; more dust caused some planets to contain heavier elements. B) The angular momentum of the solar nebula pushed the heavy elements towards the outer regions of the nebula. C) The variation in temperature throughout the solar nebula; the higher the temperature, the lower the percentage of light elements in the forming planet. D) The innate variation of chemical composition of the original nebula; the outer parts of the nebula contained a greater abundance of heavy elements. E) The angular momentum of the forming planet; faster rotating planets lost the lightest elements. 28) When we are lucky enough to see an extra-solar planet transit its star 28) A) we can determine its shape. B) we can be certain it is a terrestrial, not a jovian. C) we can determine what elements are in its atmosphere. D) it will cause the star to vanish for several hours. E) we can by the drop in light find the planet's size, mass, and density. - 4 -
29) As the solar nebula contracts it 29) A) flattens out into the ecliptic plane around the Sun's poles. B) spins faster due to conservation of angular momentum. C) reverses it direction of rotation. D) loses angular momentum. E) cools due to condensation. 30) The meteorites that strike Earth are 30) A) the oldest rocks known. B) pieces of comets that fall to Earth. C) mostly made of iron. D) the remains of the planet between Mars and Jupiter. E) material from outside our solar system. 31) Compared to Ida, Eros, and Gaspra, what was odd about Mathilde? 31) A) It was less dense than rock, but more than ice, suggesting a porous structure. B) It had a small moon, so we could more accurately find its mass. C) It was much denser, probably made of iron and nickel, a class M asteroid. D) It was less dense than water, indicating it was a comet nucleus, rather than an asteroid. E) It was the same density as the Earth's moon, indicating it had been knocked off our moon. 32) What is true about solar system densities? 32) A) The denser planets lie closer to the Sun. B) Saturn has the same density as water. C) Planetary density increases with increasing distance from the Sun. D) In differentiated bodies, the denser materials lie near their surfaces. E) The asteroids all have about the same density. 33) Meteor shower debris is believed to come from 33) A) the disintegration of a short period comet over many returns to the Sun. B) the core of a differentiated type M asteroid, now broken up. C) the asteroid belt when Mars deflects it toward us annually. D) the crust of a differentiated type C asteroid, now broken up. E) deep space, far beyond the solar system, deflected by the gravity of another star. 34) Pluto was discovered in 34) A) ancient times. B) 1789. C) 1859. D) 1930. E) 1992. 35) In terms of composition 35) A) the Sun is unique, made of nothing but hydrogen and helium. B) the terrestrials are more like the Sun, since they formed close to it. C) the jovian planets are made only of ice, and the terrestrials only of rock. D) the jovian planets are more like the Sun than are the terrestrials. E) all planets condensed from the same nebula, and have similar compositions. - 5 -
36) The two names most associated with the discovery of Pluto are 36) A) Herschel and Bode. B) Adams and Leverrier. C) Kuiper and Whipple. D) Lowell and Tombaugh. E) Shoemaker and Levy. 37) The orbits of most asteroids 37) A) lie beyond Neptune. B) cross the orbit of Earth. C) lie entirely beyond the orbit of Mars. D) cross the orbit of Mars. E) cross the orbits of all four terrestrial planets. 38) How did Mercury's location in the solar system affect its composition? 38) A) Mercury is rich in metals because only metallic grains could survive the high temperatures so near the Sun. B) Because Mercury is so near the Sun, its composition is similar to the Sun; mostly hydrogen and helium. C) The nearby Sun caused ice in Mercury's interior to melt into liquid water. D) Mercury is poor in metals because metallic grains could not survive the high temperatures so near the Sun. E) Mercury is more volatile than most metals, so formed closer to the hot Sun. 39) The body which wiped out the dinosaurs was about 39) A) as big as an SUV. B) as big as a 747. C) a few hundred meters across. D) as big as our Moon. E) as big as one of Mars' moons. 40) Iron meteorites are believed to come from 40) A) the core of a dense M-type asteroid, now broken up. B) the crust of a differentiated type C asteroid, now broken up. C) Mars, hence their reddish color. D) a broken up cometary nucleus, hence their shiny appearance. E) deep space, far beyond the solar system, hence their unique crystal patterns. - 6 -