For the version with the correct answers indicated, click here.
The format for our final will be like for the other tests, 30 multiple-choice and 10 short-answer questions.

University of Mississippi
ASTR 103 Sections 09-12, Fall 2003

Test 3 (Final Exam)

Mark your choice of answer for each question on your scantron card. When you are finished, make sure that your name and the test number and version are written on the scantron card. Once you have handed in the scantron card and the instructor has checked your test version, you can take this test with you.

(1) How far is Mars from the Sun?
a. 5 times as far as the Earth.
b. 20 times as far as the Earth.
c. Half of our distance from the Sun.
d. 1.5 times our distance from the Sun.

(2) Does Mars have volcanoes?
a. No, at least not as far as we know.
b. Yes, but much smaller than the Earth's, dead and eroded.
c. Yes, they are smaller than the Earth's, but very active.
d. Yes, some are much larger than the Earth's, but seem to be inactive.

(3) Does any meteoroid ever enter the Earth's atmosphere?
a. Yes, but they all burn up before reaching the ground.
b. Yes, most burn in the atmosphere but some larger ones hit the surface.
c. No, we have been lucky; any meteoroid would cause major destruction.
d. No, all meteoroids disappeared millions of years ago.

(4) What was the Tunguska event?
a. The impact of a large asteroid that killed the dinosaurs 65 million years ago.
b. A comet that exploded in the atmosphere in 1908, flattening a large area in Siberia.
c. One of the brightest meteor showers in recorded history, which happened in 1833.
d. An asteroid that came so close to Earth in 1054 that it looked bigger than the Moon.

(5) Why is Antarctica a good place to look for meteorites?
a. Because most of them have not been already taken away by people.
b. Because they are easier to see in the ice.
c. Because most of the meteorites that come to Earth fall there.
d. Because the ice prevents them from burning up or melting away.

(6) What causes a meteor shower?
a. Charged particles from the Sun entering the atmosphere.
b. The Earth going through comet debris.
c. A star exploding into many pieces that reach our atmosphere.
d. The Earth going through the asteroid belt.

(7) Where did the planet Jupiter get its name from?
a. The supreme god of the Romans.
b. The Norse god of abundance.
c. The Roman god of war.
d. The Roman god of the sea.

(8) How does Jupiter's radius compare to that of the Earth?
a. It is slightly smaller than the Earth's.
b. It is about twice as large as the Earth's.
c. It is about 11 times as large as the Earth's.
d. It is about 50 times as large as the Earth's.

(9) How big is the Great Red Spot on Jupiter?
a. Bigger than the whole Earth.
b. Bigger than the whole planet Saturn.
c. About the size of a large city.
d. About 600 miles across.

(10) What is special about Saturn's moon Titan?
a. It is the only moon entirely made of gas.
b. There is liquid water under its icy surface.
c. It has an unusually thick atmosphere.
d. There are active volcanoes on its surface.

(11) Does Jupiter have moons?
a. No.
b. Yes, one, the largest in the solar system.
c. Yes, four, first seen by Galileo.
d. Yes, at least 61.

(12) Why are Saturn's rings sometimes very bright, other times barely visible?
a. Because the distance between the Earth and Saturn changes.
b. Because they are activated by the solar wind, which varies.
c. Because they are tilted and we see them at different angles.
d. Because their brightness depends on the number of stars behind them.

(13) Does Saturn have volcanoes?
a. We haven't seen any yet, but the Cassini spacecraft will look.
b. No, there can be volcanoes only on planets with solid surfaces.
c. Yes, in fact material ejected by the volcanoes formed the rings.
d. Yes, but because Saturn is so massive, the volcanos are small.

(14) What are Saturn's rings made of?
a. A dense plasma of hot gas kept in place by a magnetic field.
b. A large amount of loose ice particles and small dirty ice balls.
c. A thin, shiny sheet of liquid water surrounding the planet.
d. A smooth, spinning solid disk of metal covered with dust.

(15) What effect has the moon Mimas had on Saturn's rings?
a. Its resonance with ring particles produces the gap called the Cassini division.
b. It collides with ring particles and prevents them from extending further out.
c. Its orbit crosses the rings and produces holes in them when Mimas goes through.
d. The rings were produced when Mimas broke up long ago into small fragments.

(16) What does Uranus' surface look like?
a. Like an orange-brown gas ball with turbulent cloud bands.
b. Like a smooth blue-green gas sphere.
c. Like a ball of cracked ice with frozen swirls from impacts.
d. Like a cratered, dark and rocky body.

(17) What is the main difference between comets and asteroids?
a. An asteroid is called a comet if it develops a tail.
b. Comets shine because they emit light, asteroids don't.
c. Asteroids are made of rocky material, comets are icy.
d. Comets sometimes come near the Earth, asteroids don't.

(18) How large are the largest asteroids?
a. The largest known ones are football-sized.
b. Like boulders, at most 2-3 meters.
c. Between 100 and 200 m wide.
d. Several hundreds of km wide.

(19) Why are most asteroids not round like planets are?
a. Because they are exposed to a larger amount of radiation and solar wind.
b. Because they don't rotate as fast as planets do.
c. Because they have been carved by many collisions.
d. Because their gravity is not strong enough to make them round.

(20) Can asteroids have their own moons/satellites?
a. Yes, we have already seen several which do.
b. It's possible, but we haven't yet seen any that do.
c. No, they are way too small to have satellites.
d. No, because they themselves orbit other objects.

(21) Which of these does Neptune most resemble, in terms of appearance and size?
a. Venus.
b. Jupiter.
c. Uranus.
d. Pluto.

(22) Is Uranus visible to the naked eye?
a. No, you need a telescope to see it.
b. Yes, it is not as bright as Venus but brighter than any star.
c. Yes, it is the brightest of all planets in the sky.
d. Yes, but barely, with very good viewing conditions.

(23) Does Uranus have rings?
a. No.
b. Yes, but fewer, darker and dimmer than Saturn's.
c. Yes, even brighter and more extensive than Saturn's.
d. We don't know yet, because we haven't sent a mission to explore Uranus.

(24) How far is Neptune from the Sun?
a. About 70 AU.
b. About 30 AU.
c. About 150 AU.
d. About 10 AU.

(25) Why do stars twinkle?
a. Because of fluctuations in starlight caused by Earth’s atmosphere.
b. Because their great distance weakens the light we get from them.
c. Because they are burning spheres of hot gas.
d. Because of their slow motion across the sky.

(26) How large is the radius of the Celestial Sphere?
a. 1 AU.
b. 2 million light years.
c. We don't know because none of our spacecraft have reached its boundary yet.
d. This is not a meaningful question, the celestial sphere is an imaginary object.

(27) Do stars rise exactly at the same time every day?
a. No, every day they rise a few minutes earlier, in terms of solar time.
b. No, every day they rise a few minutes later, in terms of solar time.
c. Yes, because the Earth goes around one full rotation.
d. Stars do not rise and set, only the Sun and the Moon do.

(28) Suppose that the Moon is new today. How long will it be until full Moon?
a. The length of time varies because of the tilt of the Moon's orbit.
b. About 2 days.
c. About 2 weeks.
d. About 2 months.

(29) Why didn't ancient astronomers see parallax for the stars?
a. The fact that the Earth moves prevents us from seeing the parallax.
b. To see the parallax we would have to be located at the Sun's position.
c. Stars are so distant that one needs a telescope to see their parallax.
d. Stars are too dim for us to see their parallax with our naked eyes.

(30) Which of these terms describes the present view we have of the solar system?
a. Geocentric.
b. Heliocentric.
c. Ptolemaic.
d. Epicyclic.

(31) Who was the first person who realized that the orbits of planets should not be thought of as circles?
a. Kepler.
b. Galileo.
c. Ptolemy.
d. Aristotle.

(32) Do planets really orbit the Sun along ellipses?
a. No, they follow small circles on top of big circles, and the result just appears to be an ellipse.
b. No, in reality only the Sun moves along an ellipse.
c. Almost, but their orbits are slightly perturbed by additional forces from objects other than the Sun.
d. Yes, because that is what Kepler's laws tell us.

(33) Which of the following objects can be found inside the Solar System?
a. Meteoroids.
b. Planetary nebulae.
c. Pulsars.
d. Quasars.

(34) What is the main difference between Terrestrial planets and Jovian ones?
a. Terrestrial ones have moons, Jovian ones don't but have rings instead.
b. Jovian ones orbit the Sun in the opposite direction to Terrestrial ones.
c. Terrestrial ones are smaller and rocky, Jovian ones larger and gaseous.
d. Terrestrial ones were all formed at the same time, Jovian ones were captured later.

(35) Where in the solar system (other than Earth) do we think there is liquid water?
a. Europa.
b. Mimas.
c. Venus.
d. Jupiter.

(36) Other than planets, which objects have spacecraft from Earth landed on?
a. None.
b. Only the Earth's Moon.
c. Our Moon and two of Jupiter's moons.
d. Our Moon and one asteroid.

(37) Why does Mercury have wide temperature variations, from extremely hot to extremely cold?
a. Because it rotates slower than the Earth.
b. Because of the runaway greenhouse effect.
c. Because it is closer to the Sun than the Earth.
d. Because it doesn't have an atmosphere.

(38) How was the solar system formed?
a. The planets formed out of debris from a violent collision suffered by the Sun.
b. The Sun and the planets formed together from a cloud of gas and dust.
c. The Sun ejected the material that formed the planets over billions of years.
d. The planets were captured by the Sun as they were drifting in space.

(39) How many stars are in our Solar System?
a. None.
b. One, the Sun.
c. At least 50.
d. About 100 billion.

(40) What is a planetesimal?
a. A planet which is drifting in space without orbiting a star.
b. One of the layers into which a planet's interior is divided.
c. An object formed by accretion which may later become part of a planet.
d. One of the pieces into which a planet breaks when hit by an asteroid.

(41) What happens during the process of fragmentation?
a. Atoms and molecules in a gas join to form solid particles.
b. Smaller clumps of solid matter stick together to form larger ones.
c. Matter falls toward the center of a nebula and forms a star.
d. Planetesimals in the early solar system collide and break up.

(42) Is there a tenth planet in the solar system?
a. Maybe, some astronomers have reported a Neptune-sized one at 60 AU.
b. Yes, a tenth planet (so far unnamed) was discovered last year.
c. Not any more, but there used to be a planet where the asteroid belt is now.
d. No; the only possibility would be a very distant one, at thousands of AU.

(43) To what extent have our spacecraft explored Mercury?
a. It has only been visited by spacecraft flybys in the 1970's.
b. Some of the Mariner spacecraft landed and took pictures.
c. A Soviet manned spacecraft landed and brought back samples.
d. One of the Apollo missions took three astronauts there.

(44) Why would we see a wobble in the motion of a star that has planets around it?
a. Because the star feels a gravitational pull from the planets.
b. Because of the magnetic field produced by the planets.
c. Because the presence of planets is what makes the star twinkle.
d. Because of the explosions that occur when those planets collide.

(45) How many extrasolar planets have we discovered so far?
a. Two, they have just been discovered last year by the Hubble Telescope.
b. More than 100 have been reported, and the list keeps growing.
c. Thousands; every star that has been carefully checked has planets.
d. None, but technology will soon reach a point where we will find them.

(46) How do the known extrasolar planets differ from the solar ones?
a. Most are smaller than the solar planets.
b. They don't all revolve in the same direction around their star.
c. Most are larger than the solar planets.
d. Most of them are wandering in space, instead of orbiting a star.

(47) Which of these planets is most similar to Earth in size?
a. Venus.
b. Mars.
c. Mercury.
d. Jupiter.

(48) What consequences has the greenhouse effect had on Venus?
a. Little or no effect, because the atmosphere is too thin.
b. It has made the planet colder by about 300 degrees Kelvin.
c. It has made the planet much hotter by trapping the released heat.
d. It had initially allowed plants to grow, before it became too cold.

(49) How long does it take for the Moon to rotate once around its axis?
a. One (lunar) month.
b. The Moon does not rotate.
c. 365 days.
d. 24 hours.

(50) Why does the far side of the Moon have more craters than the near side, and fewer "maria"?
a. Because the far side has been hit more often by asteroids.
b. Because the core of the Moon if off-center, and the crust is thicker on the far side.
c. Because heat from the Earth has melted the surface on the near side.
d. Because the Moon's atmosphere has eroded the craters on the near side.

(51) Why does Neptune's surface look bluish in photographs?
a. Because its light is blueshifted by the Doppler effect.
b. The blue is just a false color in pictures taken from a distance.
c. Because light from it has to travel a long distance to reach us.
d. Because of the frozen methane clouds in its cold atmosphere.

(52) What is unusual about Pluto's orbit?
a. It is retrograde.
b. It is smaller than the orbit of Neptune.
c. It does not follow Kepler's laws.
d. It is considerably tilted and eccentric.

(53) Why don't we have any good pictures of Pluto's surface?
a. It is always covered by a thick cloud layer.
b. No spacecraft from Earth has been near it.
c. The camera on the orbiting spacecraft is damaged.
d. It is too dark out there for our cameras.

(54) If we didn't consider Pluto a planet, how could it be classified?
a. Asteroid.
b. Meteorite.
c. Kuiper belt object.
d. Oort cloud object.

(55) Which of these objects is larger than Pluto?
a. The asteroid Ceres.
b. The Earth's Moon.
c. Halley's comet.
d. None of the above.

(56) What is the Kuiper belt?
a. A ring around an impact crater on an asteroid's surface.
b. The region around a planet inside which tidal forces are strongest.
c. One of the gaps in the asteroid belt produced by resonances with Jupiter.
d. A part of the Solar System beyond Neptune where many comets come from.

(57) How large are the largest comets?
a. About 50-100 meters.
b. Comets are at most a few feet wide.
c. More than 100 km wide.
d. No larger than a grain of sand.

(58) In what direction does the tail of a comet point?
a. Backwards, away from the direction in which the comet moves.
b. Away from the Sun, because it is pushed away by the solar wind
c. Toward the Sun, because it is attracted by its gravity.
d. Toward the Lagrange point of Jupiter's orbit.

(59) Where did all the water on the Earth's surface come from?
a. It was collected from a cloud of gas and dust during the Earth's formation.
b. Probably from many comets arriving on Earth over a long period of time.
c. From a heavy rain carried by the solar wind 4 billion years ago.
d. It rose to the surface when the heavier material sank to the core.

(60) Which are the farthest known objects in the solar system?
a. The asteroids in the asteroid belt.
b. The comets in the Oort cloud.
c. The comets in the Kuiper belt.
d. Pluto and its moon.