astronomy final 1010

The classical model of the hydrogen atom that explains its spectral line structure is due to:

Bohr.

Compare the atmospheres of Mars and Venus.

Both are chiefly carbon dioxide, but at Mars it can freeze as dry ice.

Which statement about Mars' two moons is FALSE?

Both are in retrograde orbits.

How does the magnetic tilt of Jupiter compare with our field?

Both are tilted about 10 degrees, but Jupiter is opposite in polarity.

Which statements about the magnetic fields of Uranus and Neptune is FALSE?

Both pass directly through the cores of their planets, like all other fields.

The type of asteroid that would appear darkest and reflect the least light is type: A) A. B) B. C) C. D) D. E) S.

C) C.

The type of asteroid that would appear darkest and reflect the least light is type

C.

What is the source of the material of a meteor shower? A. Solar wind B. Oort cloud C. Comets D. Collisions among asteroids

C. Comets

Which of the following is NOT one of the criteria necessary to classify an object as a major planet? A. It must have enough self-gravity to be approximately spherical. B. It has cleared its neighborhood around its orbit of other bodies. C. It must have at least one moon orbiting around it. D. It must orbit the Sun.

C. It must have at least one moon orbiting around it.

The orbits of most comets: A. are like the planets, fairly circular and in the ecliptic plane. B. are shorter than the 76 year period for Comet Halley. C. lie almost entirely beyond the orbit of Neptune. D. go no farther out than Pluto, then return to the Sun again. E. have perihelions within the orbits of Mercury.

C. lie almost entirely beyond the orbit of Neptune.

The tails of a comet A. curve from right to left. B. point opposite the direction of motion of the comet. C. point away from the Sun. D. curve clockwise with the interplanetary magnetic field.

C. point away from the Sun.

The Trojan asteroids have orbits that: A. cross the orbit of Earth at perihelion. B. stay out beyond Neptune. C. stay sixty degrees ahead of or behind Jupiter. D. cross the orbit of Mars, but not Earth, at perihelion. E. are, on average, closer to the Sun than we are.

C. stay sixty degrees ahead of or behind Jupiter.

Iron meteorites are believed to come from: A. the crust of a differentiated type C asteroid, now broken up. B. a broken up cometary nucleus, hence their shiny appearance. C. the core of a dense M-type asteroid, now broken up. D. deep space, far beyond the solar system, hence their unique crystal patterns. E. Mars, hence their reddish color.

C. the core of a dense M-type asteroid, now broken up.

Which of these spacecraft went into orbit about Saturn in July 2004?

Cassini

What is the space probe that is currently orbiting Saturn and is responsible for numerous discoveries of storms and weather patterns in Saturn's atmosphere called?

Cassini.

The three largest asteroids are

Ceres, Pallas, and Vesta.

The largest asteroid, and probably the only one to be a spherical "world" is

Ceres.

What is the defining property of the Trojan asteroids? A. They have orbits at the distance of Jupiter and 60 degrees ahead of or behind it. B. Like Pluto, they are in a 3:2 resonance with Neptune. C. Their orbital periods are exactly one year, like ours. D. They have orbits between Saturn and Uranus. E. They have orbits that cross the orbit of the Earth, but not that of Venus.

A. They have orbits at the distance of Jupiter and 60 degrees ahead of or behind it.

Spectral lines are often referred to as the stars' "fingerprints" because:

All of these are correct.

When a formal definition of a planet in the solar system was adopted, Pluto was reclassified as a dwarf planet. What characteristic of planets does NOT describe Pluto? A. Planets orbit in ellipses with low eccentricity. B. Planets have cleared the neighborhood around their orbit. C. Planets orbit the Sun. D. Planets are approximately spherical. E. Planets orbit in or very near the ecliptic plane.

B. Planets have cleared the neighborhood around their orbit.

The asteroids that cross the orbit of Earth belong to a group called the ________. A. Juno asteroids B. Kuiper asteroids C. Trojan asteroids D. Apollo asteroids E. Amor asteroids

D. Apollo asteroids

Which three Galilean moons were found by Galileo to have weak, changing magnetic fields?

Europa, Ganymede, and Callisto

What evidence suggests that Enceladus has ongoing geological activity?

Lack of impact craters on much of its surface and evidence of ice flows from possible volcanic activity.

Which of these is not a characteristic of the solar nebula theory?

Larger planets should form closer to their star, where there is more debris.

In what two ways is Titan's atmosphere like our own? Now name two differences. (SA)

Like the earth's, Titan's atmosphere is made chiefly of nitrogen, and it is at about the same barometric pressure as the earth at both surfaces. However, it is much colder, lacks any substantial oxygen, and its clouds are made of methane and other hydrocarbons, not water droplets like ours.

What material makes up most of Jupiter's volume, and why is it not found here? (SA)

Liquid metallic hydrogen can be formed only under tremendous pressure, not found even in the Earth's interior, much less on its surface.

What is the name of the theory that is currently used to describe the formation of the solar system?

Nebular theory

Which planet had the Great Dark Spot in 1989, but had lost it by 1995?

Neptune

In addition to Saturn's Titan, which other moon has a nitrogen atmosphere?

Neptune's Triton

Why will it be hard to determine the nature of Venus' interior?

No seismograph can last long enough at Venus' temperatures to pick up quakes.

Which of these was the first to cross the asteroid belt and head to Jupiter?

Pioneer 10

(SA) What is the evidence that suggests the past and present existence of surface water on Mars?

Runoff channels from old rivers and outflow channels from catastrophic flooding in the distant past. Recent mudflows down the sides of some canyons and crater walls suggest occasional eruptions of liquid water persist to this day, as imaged by the Global Surveyor. The Rovers in 2004 also found clear evidence of sedimentary rocks formed under water at both the landing sites, on opposite sides of the globe.

The only spacecraft to successfully land on Venus were:

Russian Veneras.

Which of these bodies has the lowest density?

Saturn

Which of the following played the most important role in the ring's formation?

Saturn's Roche limit

Contrast the compositions of Jupiter's belts and zones. (SA)

The zones are high, cold regions of ammonia ice crystals, white in color. But the lower, warmer belts are brownish from complex chemistry involving hydrogen sulfide, ammonia, and other chemicals.

What piece of evidence suggests that the martian moons did not form with Mars?

Their composition is significantly different from Mars and the terrestrial planets.

What is the role of irregularities in the solar system in terms of theories of its origin?

They introduce a need for flexibility in theories of the solar system's origin.

Why are the Jovian planets so large? (SA)

They were far enough from the Sun that low temperatures allowed most materials to condense out of the nebula, forming planetesimals so large that they attracted and held nebular helium and hydrogen.

How would sunspots appear if you could magically remove them from the Sun?

They would shine bright orange in color, like Arcturus.

The observed spectral lines of a star are all shifted towards the red end of the spectrum. Which statement is true?

This is an example of the Doppler effect.

In the time between two closest approaches to Earth, Venus rotates almost exactly five times relative to the sun. The consequence of this is that:

Venus always presents the same face to Earth at inferior conjunction.

The synodic period of Venus is the time it takes for:

Venus to complete a full cycle of phases.

The reason that the atmosphere of Venus is over 95% carbon dioxide is thought to be because:

Venus was much hotter than Earth when its atmosphere formed.

Which of these is not a consequence of resonance?

Venus' cloud and surface rotation rates

Venus' lack of magnetic field means that:

Venus' upper atmosphere is permanently ionized.

Rank these magnetic fields, from weakest to strongest.

Venus, Mars, Mercury, Earth

The first successful landers on the surface of Mars were:

Vikings 1 and 2 in 1976.

The NASA missions that landed on Mars in 1976 were the

Vikings I and II.

The only spacecraft to have visited Uranus and Neptune was:

Voyager 2

The "Grand Tour" of all four jovians was conducted by:

Voyager 2.

Is there evidence of life on Mars?

We have confusing and uncertain results to date.

Why couldn't you stand on the Sun's surface?

The Sun doesn't have a solid surface.

Which of the following is true about the seasons on Uranus?

The Uranian rotation axis produces some extreme seasonal effects.

Evidence of liquid water in Mars' distant past suggests that it had a substantial atmosphere compared to what it has presently. What happened to its water vapor?

The atmosphere has frozen out into the polar ice caps and permafrost as Mars has cooled.

Why was it thought that Titan may have oceans of methane?

The atmospheric pressure at Titan's surface and its surface temperature are such that methane should be liquid on Titan's surface.

If Venus once had an ocean, where did it go?

The water broke into hydrogen, which escaped to space, and oxygen, which became trapped in the planet's surface rocks.

What is thought to be the reason that there are no small impact craters on Mars?

The wind blows small dust particles, eroding the surface of Mars, erasing small impact craters faster than they can form.

A loop of gas following the magnetic field lines between sunspots' poles is

a prominence.

Which of these is the classic continuous spectrum?

a rainbow

Typical stellar spectra appear as:

a rainbow, but with some dark lines mixed in.

One of the discoveries made by the Voyager probes while near Jupiter was

a thin ring of dust around the equator.

A meteorite is

a chunk of space debris that has struck the ground.

The Kuiper Belt is

a collection of asteroid-sized icy bodies located outside the orbit of Neptune.

Venus has a feature named Aphrodite Terra. What is this feature?

a continental-sized plateau

The Cassini spacecraft found evidence that the E Ring is related to Enceladus through

a continual supply of icy particles spewed via volcanism on Enceladus.

An incandescent light (glowing tungsten filament) produces:

a continuous spectrum, with the peak giving the temperature of the filament.

Compared to Earth, Venus has:

a far greater percentage of its surface in low-level ocean basins.

A neon light (thin hot neon gas in a sealed tube) gives us:

a few bright emission lines, telling us the gas is neon.

In 1846, Johann Galle found Neptune

a few degrees from where it was predicted to be.

What is the typical size of most known asteroids?

a few kilometers

The nucleus, or main solid body, of a comet has a typical size of

a few kilometers.

Large meteoroids are thought to collide with Earth

a few times in every million-year period.

Cassini is:

a gap in the rings created by a resonance with Mimas. the French astronomer who first discovered a gap in Saturn's rings. NASA's orbiter now taking photos of Saturn. all of the above

Essentially, the Great Red Spot is

a large cyclonic storm (hurricane).

How many planet Earths could fit inside the Sun?

a little over a million

What is thought to lie at the center of Jupiter?

a massive core of rocky materials with some iron mixed in

Which form of electromagnetic radiation is absorbed by carbon dioxide and water vapor in our atmosphere?

infrared

The smallest sort of interplanetary matter is called

interplanetary dust.

The outward pressure of hot gas in the Sun

is balanced by the inward gravitational pressure.

If a wave's frequency doubles, its wavelength

is halved.

Charon's orbit

is highly inclined to Pluto's orbital plane.

During a period of high solar activity, the corona

is more irregular.

The atmospheric pressure on Venus:

is much higher than on Earth.

Titan is an interesting moon because:

it has a rich atmosphere that may resemble that of the early Earth.

Saturn is noticeably oblate because

it is a fluid body that is spinning rapidly.

Jupiter is noticeably oblate because:

it rotates rapidly.

The most prominent feature of Mars observable from Earth is

its bright polar caps.

Mars' magnetic field is so weak because

its core contains less iron than our own. it core may no longer be molten. Both B and C are probable.

A late collision with a large planetesimal may have caused what feature on Mars?

its curious north-south asymmetry

What physical feature of Mars are atypical compared with the other terrestrial planets?

its density

About 50 years after Uranus was discovered

its orbit was too far off of its predicted path to be explained by observational errors.

As the Sun evolves into a red giant in the distant future, then according to Wien's Law:

its peak on the Planck curve will move into the infrared.

Venus is only a little bit (5%) smaller than Earth, and its density is only slightly less than Earth's. Therefore, its mass is:

just a little bit less than Earth's.

Conservation of angular momentum means that a spinning body tends to

keep spinning.

Beyond our own solar system, the planets found to date have tended to be

large jovians with orbits more like terrestrial planets.

The reason Saturn lost very little of its original atmosphere is due to its

large mass.

The reason the jovian planets lost very little of their original atmosphere is due to their

large mass.

The rilles found in Ovda Regio are evidence of:

lava flows.

Volcanic activity on Venus is thought to be:

less frequent, but more violent than volcanic activity on Earth.

What percentage of the surface of Venus could be characterized as continental-sized highlands?

less than 10%

Uranus was discovered

less than 250 years ago.

The Balmer Beta absorption line is a result of a transition of an electron in a hydrogen atom from

level 2 to level 4

The orbits of most comets

lie almost entirely beyond the orbit of Neptune.

Objects in the Kuiper belt

lie beyond the orbit of Neptune, and close to the ecliptic.

The orbits of most asteroids

lie entirely beyond the orbit of Mars.

Compared to its rotational axis, Jupiter's magnetic field:

lies about 10 degrees off, much like our own rotation and magnetic field.

What is the source of Jupiter's intense radio waves and magnetism?

liquid metallic hydrogen swirling in the rapidly spinning mantle

What is erupting out of the geysers on Triton?

liquid nitrogen with carbon grit

Which characteristic listed below describes the jovian planets?

low density

Discuss the seasons of Uranus. (SA)

Flopped over with a 98 degree tilt, Uranus' pole was pointing toward the Sun at solstice in 1986 when Voyager 2 flew past. With one hemisphere in constant daylight, the atmosphere was very bland. But by equinox in 2008, the whole planet will get eight hours of day and night, and the heating patterns are already producing more normal Jovian belts and zones. At each pole, you would get 42 years of constant Sun, then 42 years of darkness.

What spacecraft was intentionally destroyed in 2003 so that it could not hit Europa?

Galileo

Our best close-up views of the jovian moons came from the many passes by:

Galileo.

The first spacecraft to drop a weather probe into Jupiter's atmosphere was:

Galileo.

The only spacecraft to be intentionally crashed into Jupiter was:

Galileo.

The only spacecraft to go into orbit around Jupiter was:

Galileo.

Which of the jovian moons is the largest and also the largest moon in the solar system, even bigger than Mercury?

Ganymede

Which two satellites of Jupiter are considered "fraternal twins"?

Ganymede and Callisto

In size, from largest to smallest, the correct order for the Galilean moons is:

Ganymede, Callisto, Io, Europa.

Of the Galilean moons, the one with striking grooved terrain and icy tectonic features as well as older craters is:

Ganymede.

On its way to Jupiter, Galileo also gave us close-ups of

Gaspra and Ida.

The main problem spacecraft have encountered in landing on Venus is:

the extremely high temperatures.

On Bode's advice, Herschel named his newly discovered planet after

the father of Saturn.

One piece of evidence against the possibility of water on Mars is

the few carbonate rock layers that would have formed on the bottoms of oceans.

The total energy radiated by a blackbody depends on

the fourth power of its temperature.

The number of waves passing the observer per second is:

the frequency in Hertz.

A dim, young star like Herbig-Haro 68 emits most of its light in which part of the electromagnetic spectrum?

the infrared

The vibrations of the Sun reveal information about

the interior structure of the Sun.

In terms of composition

the jovians are much more like the sun than the terrestrials are.

A characteristic of shield volcanoes is the formation of a crater at the summit which occurs when:

the lava withdraws and the surface collapses.

Shepherd moons were discovered because scientists hypothesized their existence after observing

the narrow F Ring.

The meteorites that strike Earth are

the oldest rocks known.

What are Dactyl, Gaspra, Mathilde, Eros, and Ida?

the only four asteroids explored by spacecraft to date

Unlike Earth, Mars' seasons are affected (enhanced and diminished) by the distance between Mars and the Sun. This is because

the orbit of Mars is significantly more elliptical.

If satellite A is in a 2:1 resonance with satellite B, this means that

the orbit of satellite B takes twice as long to complete as that of satellite A.

Very low temperature molecular clouds emit most of their light in which part of the electromagnetic spectrum?

the radio

How many moons does Mars have?

two

What mission landed on Titan in early 2005?

Huygens

While Galileo saw Saturn as a changing oval, the real nature of the rings was discovered by:

Huygens.

The most abundant component of the atmospheres of Uranus and Neptune is

Hydrogen

Together which two gases make up 99% of Jupiter's atmosphere?

Hydrogen and Helium

Which moon of Saturn constantly changes its rotational speed and rotational axis?

Hyperion

Which Saturnian moon has the leading hemisphere black as tar, the back side icy white?

Iapetus

What property of Mars is responsible for producing the great heights of its volcanos?

Its thick crust can support larger peaks, and lower surface gravity does not pull them down as much as on Earth.

The radiation our eyes are most sensitive to lies in the color

yellow-green at about 550 nm.

The absence of a magnetic field on Venus probably stems from its:

slow rotation.

Our most detailed knowledge of Uranus and Neptune comes from

spacecraft exploration.

Evidence for a permafrost layer of ice just a few meters below the surface of Mars include

"fluidized ejecta" craters.

At closest approach Venus is about how far from Earth?

0.3 AU

How many large moons does Saturn have?

1

What is the size of a typical granule or convection cell seen in the photosphere?

1,000 km

The speed of light is 3.00 × 10⁸m/s. If 2.00 kg of mass is converted to energy, how much energy will be produced?

1.80 × 10¹⁷ J

The critical temperature the core must reach for a star to shine by fusion is

10 million K.

The critical temperature to initiate the proton-proton cycle in the cores of stars is:

10 million K.

About what percent of all asteroids are C-type asteroids?

10%

The energy required to ionize a hydrogen atom whose electron is in the ground state (energy level 1) is

13.6 eV

About what percent of all asteroids are S-type asteroids?

15%

Increasing the temperature of a blackbody by a factor of 2 will increase its energy by a factor of

16

Pluto was discovered in

1930.

Pluto's bulk density is:

2,100 kg/m3, similar to Callisto's mix of rock and ice.

Halley's Comet last passed Earth in 1986. It will be due back in

2061.

How long is a day on Mars?

24 hours, 36 minutes

Venus orbits the Sun in 225 days. How long does it take to rotate on its axis?

243 days, even though the Earth's tidal pull is not involved

The percentage (by mass) of the Sun that is Helium is about

27%

The wind speeds found in the bands and zones of Saturn, compared to those on Jupiter, are about

3 times faster.

Venus is brightest as seen from Earth:

36 days before or after inferior conjunction, appearing as a large crescent.

Which is the net result of the proton-proton chain?

4 protons = 1 helium 4 + 2 neutrinos + gamma rays

The time between equinoxes on Uranus is about

42 years

The temperature of the layer of gas that produces the visible light of the Sun is:

5,800 K

About what percent of the incoming energy from the Sun' reaches Earth's surface?

50-70%

What resonance exists between Venus' rotational period and its synodic period?

5:1, with the Earth always closest to the same side of Venus when they pass

How many medium-sized moons does Saturn have?

6

At which of these Kelvin temperatures would a blackbody radiate mostly at visible wavelengths?

6000 K

The major impact in the Yucatan wiped out the dinosaurs about:

65 million years ago.

The percentage (by mass) of the Sun that is Hydrogen is about

71%

At the equator during the equinoxes on Uranus a day lasts

8 hours.

Increasing the temperature of a blackbody by a factor of 3 will increase its energy by a factor of

81

The percentage (by number of atoms) of the Sun that is Hydrogen is about

91%

(SA) A solar flare creates a radio disturbance on Earth a few minutes after going off and again several days later. Explain.

A flare will give off intense X-rays and ultraviolet light, which travels to Earth in about 8 minutes. But also given off is an intense burst of high energy particles which travel to the Earth at speeds much less than the speed of light. They can take several days to reach the Earth. Both forms of radiation create radio disturbances when they reach the Earth.

About what percent of all asteroids are S-type asteroids? A. 10% B. 15% C. 75% D. 5% E. 50%

A. 10%

Which of the following characterizes the Kuiper belt? A. It is a disk-like region between the outer planets and the Oort cloud. B. It is up to 100,000 AU in size and spherical in shape. C. It lies between the orbits of Mars and Jupiter. D. It is a stable region just ahead of Jupiter in its orbit. E. It is the region occupied by the Earth-crossing Apollo asteroids.

A. It is a disk-like region between the outer planets and the Oort cloud.

Trojan asteroids orbiting at Jupiter's Lagrangian points are located A. behind and in front of Jupiter, sharing its orbit. B. close to Jupiter. C. far outside Jupiter's orbit. D. between Mars and Jupiter.

A. behind and in front of Jupiter, sharing its orbit.

Spectroscopic studies indicate that the majority of asteroids contain large fractions of A. carbon. B. silicate rocks. C. ice. E. iron and nickel.

A. carbon.

The orbits of most asteroids: A. lie entirely beyond the orbit of Mars. B. cross the orbit of Mars. C. cross the orbit of Earth. D. cross the orbits of all four terrestrial planets. E. lie beyond Neptune.

A. lie entirely beyond the orbit of Mars.

Carbonaceous meteorites are believed to come from: A. the crust of a differentiated C type asteroid, now broken up. B. a broken up cometary nucleus, dark like Comet Halley's nucleus. C. deep space, far beyond the solar system, hence their very low density. D. the core of a differentiated type M asteroid, now broken up. E. coal formed on Mars, then blown into space by asteroid impacts.

A. the crust of a differentiated C type asteroid, now broken up.

Based on observations by the Dawn spacecraft, scientists have concluded that Vesta might be: A. the only remaining protoplanet in our solar system. B. a planetesimal leftover from the solar system's formation. C. a fragment of Mars. D. one of the remnants of the planet that broke up to form the asteroid belt. E. one of the dwarf planets in our solar system.

A. the only remaining protoplanet in our solar system.

Kuiper belt objects are not regarded as planets because A. their masses are too low to clear other bodies from their orbital paths. B. they orbit too far from the Sun. C. they are all irregular in shape without exception. D. they are predominantly icy in composition.

A. their masses are too low to clear other bodies from their orbital paths.

Which three played a role in the finding of Neptune?

Adams, Leverrier, and Galle

(SA) What do Pioneer 10 and 11 and Voyager 1 and 2 all have in common?

All four of them flew past Jupiter, and all but Pioneer 10 past Saturn as well. All are now moving so fast from the gravity assists that they are far beyond Pluto, and escaping the Sun's gravity entirely, to become eventually lost in interstellar space.

Which statement about Jupiter's moons is FALSE?

All have counterclockwise revolution around the giant planet.

How do the densities of the jovian and terrestrial planets compare?

All terrestrials are more dense than any of the jovians.

(SA) Why is studying the neutrino so vital to understanding the solar interior?

Alone of all the products of the proton-proton cycle, only the neutrino can easily escape the Sun and reach the Earth at almost the speed of light. The flux of neutrinos should be in agreement with the observed solar constant, if our model of solar energy production is correct.

In the atmospheres of the jovian planets, this component decreases, systematically, with distance from the Sun.

Ammonia

Which of the following objects never collide with the Earth?

Amor asteroids

The most famous asteroid impact scar on Earth is located in

Arizona.

Why does Venus appear so bright to the eye?

As seen from Earth, the disk of Venus can appear larger than any other planet's. The planet's cloud-cover is highly reflective, reflecting 60% of the sun's light. Venus is closer to the Sun, so gets more intense sunlight. It gets closer to us than any other planet does. All of the above are correct.

Nearly every aspect of astronomy is related in some way to the existence of gravity and to the motions which are responsible for a balance against gravity. How does this balance play a role for the miscellaneous objects of the solar system (i.e., the asteroids and comets)? How can some aspect of this be used as a tool to determine masses in the solar system? (SA)

Asteroids and comets all orbit the Sun, some with highly eccentric orbits. Some comets have periods of millions of years. Gravity acting on and between comets and asteroids can be used to determine their masses and the masses of bodies affecting them.

The Perseid meteor shower gives us about a meteor every minute in mid

August.

Large meteoroids are thought to collide with Earth: A. about once a century. B. a few times in every million-year period. C. at least once a decade. D. never; only comets are thought to collide with Earth. E. once every billion years.

B. a few times in every million-year period.

The tail of a comet always points: A. toward the Sun and disappears at perihelion. B. away from the Sun and becomes longest and brightest at perihelion. C. in the direction of the comet's motion. D. away from the Sun and disappears at perihelion. E. toward Earth and never varies.

B. away from the Sun and becomes longest and brightest at perihelion.

Compared with the orbits of the short-period comets, the orbits of long-period comets A. look like short-period orbits, but are simply much larger. B. can come from all directions. C. are much less eccentric. D. tend to lie in the plane of the ecliptic.

B. can come from all directions.

The Apollo and Aten asteroids have orbits that: A. cross the orbit of Mars, but not the Earth, at perihelion. B. cross the orbit of Earth at perihelion. C. remain between Mars and Jupiter, in the main belt. D. stay sixty degrees ahead of or behind Jupiter. E. stay out beyond Neptune.

B. cross the orbit of Earth at perihelion.

The Amor asteroids have orbits that: A. stay out beyond Neptune. B. cross the orbit of Mars, but not Earth, at perihelion. C. stay closer to the Sun, on average, than we do. D. stay sixty degrees ahead of or behind Jupiter. E. cross the orbit of Earth at perihelion.

B. cross the orbit of Mars, but not Earth, at perihelion.

The tail of a comet can consist of ________. A. rocky pebbles B. dust and gas C. rocky boulders D. ice chunks E. blonde hair

B. dust and gas

The Kuiper Belt objects have orbits that: A. stay sixty degrees ahead of or behind Jupiter. B. stay out just beyond Neptune and close to the ecliptic. C. carry them thousands of A.U. beyond the Sun. D. cross the orbit of Mars at perihelion. E. cross the orbit of Earth at perihelion.

B. stay out just beyond Neptune and close to the ecliptic.

Meteor shower debris is believed to come from: A. the asteroid belt when Mars deflects it toward us annually. B. the disintegration of a short period comet over many returns to the Sun. C. deep space, far beyond the solar system, deflected by the gravity of another star. D. the core of a differentiated type M asteroid, now broken up. E. the crust of a differentiated type C asteroid, now broken up.

B. the disintegration of a short period comet over many returns to the Sun.

(SA) Describe how conditions on Venus have produced a runaway Greenhouse Effect.

Because of Venus' proximity to the Sun, carbon dioxide never got absorbed by surface rocks due to higher temperature. Carbon dioxide is a greenhouse gas and traps heat, so this led to still higher temperature, leading to even more carbon dioxide released from rocks in a vicious cycle. The result is a surface temperature of 730 K.

Where is Jupiter's ring located? What is it made of, and why? (SA)

Between the top of Jupiter's clouds and the orbit of the closest moon; the ring also orbits just above Jupiter's equator. It may be in part debris from Io's violent volcanoes, and dust from the breakup of the tiny moons Tethys and Adrastea, both so close to Jupiter they are under great tidal stress. Ice particles like Saturn's rings cannot exist to close to hot Jupiter, which gives back into space twice the energy it gets from the Sun.

The Oort Cloud is thought to be: 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 spherical cloud of comets and some larger icy bodies surrounding the outer solar system. D. the cloud of gas and dust from which our solar system formed. E. the material in the ecliptic plane that creates the zodiacal light.

C. the spherical cloud of comets and some larger icy bodies surrounding the outer solar system.

Of the Galilean satellites, which has the oldest, most heavily cratered surface?

Callisto

Which of the four Galilean moons is not differentiated?

Callisto

Which of the following is considered "interplanetary matter"?

Comet Hale-Bopp

About how many potentially hazardous asteroids pass within 0.05 AU of the Earth per decade in modern times? A. None B. 5000-1000 C. 10-20 D. 200-300 E. A completely unknown quantity; it could easily be anywhere from just a few to millions.

D. 200-300

Pluto's density is most similar to: A. Saturn, but not Jupiter, Uranus, or Neptune. B. the jovian planets. C. the terrestrial planets. D. moons of the jovian planets. E. Mercury, but nor Venus, Earth, or Mars.

D. moons of the jovian planets.

The most common type of meteorite to strike Earth is ________. A. iron B. rocky iron C. carbonaceous D. rocky

D. rocky

A meteorite is a piece of interplanetary debris that A. burns up in Earth's atmosphere. B. misses Earth's surface. C. glances off Earth's atmosphere. D. survives the trip to the surface.

D. survives the trip to the surface.

Meteorites are valuable to astronomers because: A. they contain diamonds and gold. B. they originated in other solar systems. C. they prove that life can only exist on the Earth. D. they may provide evidence about the process in which the solar system was born. E. they reveal the contents of interstellar space.

D. they may provide evidence about the process in which the solar system was born.

What will happen to Triton in the distant future, based on its present orbit? (SA)

Due to its retrograde orbit, it will spiral into Neptune and be torn apart into a ring when it reaches Neptune's Roche Limit. Its tidal forces will probably also heat up Neptune still more; it is already warmer than Uranus

How does the melting and vaporization point of materials determine the composition of the planets?

Durable solids that are very hard to melt and vaporize form close to the Sun, making terrestrial planets.

What was the primary role of dust in the formation of the solar system?

Dust acted as condensation nuclei; platforms to which other particles could attach and form larger particles of matter.

About what percent of all asteroids are C-type asteroids? A. 10% B. 15% C. 5% D. 50% E. 75%

E. 75%

Which of the following objects never collide with the Earth? A. Aten asteroids B. short period comets C. long period comets D. Apollo asteroids E. Amor asteroids

E. Amor asteroids

The three largest asteroids are: A. Deimos, Phobos, and Athos. B. Halley, Hale-Bopp, and Hyakutake. C. Pluto, Sedna, and Quaoar. D. Ida, Gaspra, and Mathilde. E. Ceres, Pallas, and Vesta.

E. Ceres, Pallas, and Vesta.

From its orbit, we now recognize Pluto as one of the largest members of the: A. asteroid belt. B. moons of Neptune. C. Zodiacal Belt. D. Oort Cloud. E. Kuiper Belt.

E. Kuiper Belt.

The type of asteroid that would be the densest would be type: A. Z. B. V. C. C. D. S. E. M.

E. M

Most of the asteroids orbit the Sun in a belt between the orbits of ________. A. Earth and Mercury B. Mars and Earth C. Venus and Mars D. Jupiter and Saturn E. Mars and Jupiter

E. Mars and Jupiter

Long period comets are thought to reside mainly in the: A. Kirkwood gaps. B. Interstellar Medium. C. asteroid belt. D. Kuiper Belt. E. Oort Cloud.

E. Oort Cloud.

Which of the following gives direct information about the age of the solar system? A. Martian meteorites B. the oldest lunar basalts C. the solar wind D. the oldest Martian basalts E. meteorites from asteroidal debris

E. meteorites from asteroidal debris

While not yet observed in eruption, it is likely that ________ has active volcanoes; it certainly has one hemisphere greatly reworked by tectonic and volcanic forces.

Enceladus

(SA) Describe the transport of energy, from the deep interior of the Sun, to when it finally reaches the Earth. Include the various methods of transport.

Energy is produced in the core. It enters the radiative zone, where it moves as radiation. As it gets further out from the center, the gas gets less ionized and so more opaque to radiation. In this region the energy moves by convection, with hot gas physically rising through the Sun. When it reaches the surface, or photosphere, the low density makes the Sun transparent, and the energy escapes as light.

The largest Kuiper Belt body is

Eris.

The surface of which jovian moon most resembles the pack ice of the Arctic Ocean?

Europa

In 1989, Neptune was found to have a huge storm named the

Great Dark Spot

In 1989, Neptune was found to have a huge storm named the:

Great Dark Spot.

The most striking "cloudmark" in Jupiter's atmosphere is the:

Great Red Spot.

Why does Saturn radiate even more excess energy than Jupiter?

Helium rain gives off heat as it differentiates toward Saturn's center.

The deepest depression found on the surface of Mars is the

Hellas Basin of Mars.

The largest and deepest impact basin found on Mars is:

Hellas.

Which of the Galilean moons is the densest and most geologically active?

Io

On what basis did Herschel think he had found a comet?

It appeared to be moving slightly night by night. It was not a point of light, like a star should appear. The object appeared as a small greenish disk in his telescope. No star appeared in that position on his charts. All of the above are correct.

What did the Voyager mission discover about Cassini's Division?

It contains several ringlets.

What is true of Jupiter's magnetosphere?

It has a tail that extends at least to Saturn's orbit.

What is interesting about Saturn's large moon Titan?

It has an atmosphere.

What is the result of the Greenhouse effect on the surface environment of Venus?

It has raised the surface temperature by hundreds of degrees Celsius

What happens when a solar nebula contracts?

It heats up, It flattens out, It spins faster; all of the above

How large is Jupiter's magnetosphere?

It is a million times the volume of the Earth's, extending beyond the orbit of Saturn.

How does the axial tilt of Mars compare with our own?

It is almost identical to the Earth.

Which of these is true about the seasons of Uranus?

Its strange tilt produces extreme seasonal variations, especially at the poles.

In the proton-proton cycle, the helium atom and neutrino have less mass than the original hydrogen. What happens to the "lost" mass?

It is converted to energy.

What is so unusual about Pluto's orbit?

It is more inclined to the ecliptic than any of the eight planets.

(SA) If the corona is so hot, why must we wait for a total solar eclipse to glimpse it?

It is so hot that almost all the energy it gives off, by Wien's Law, is not going to be in the visible, but the X-ray portion of the spectrum. Also, it is very low density, so there are far more atoms at 5,800 K giving off a lot of visible light than the few out in the corona.

What is interesting about Jupiter's rotation period?

It is the fastest in the solar system.

Why is Galileo Regio, the large circular feature on Ganymede, so dark?

It is the result of micrometeorite dust settling onto it over several billion years.

How does the mass of Jupiter compare with that of the other planets?

It is twice as massive as all other planets combined.

Which of the following characterizes a shield volcano?

It sits above a hot spot in the planet's mantle.

What makes Mimas a distinct moon?

It suffered a huge meteorite impact that must have nearly shattered it.

Compared to Ida, Eros, and Gaspra, what was odd about Mathilde?

It was less dense than rock, but more than ice, suggesting a porous structure.

Which statement about Pluto's discovery is FALSE?

It was the massive jovian Lowell described as "Planet X" in his calculations.

What is the prediction for the future of Triton?

It will provide the raw material for a future Neptunian ring.

Which of the following contributes to Venus being so hot?

Its atmosphere is made chiefly of carbon dioxide. It is closer than Earth to the Sun. It has very little axial tilt so the equator is always directly exposed to the Sun. Its atmosphere is much denser than the Earth's. All of the above are factors.

How does the density of Jupiter compare to the terrestrial planets?

Its density is less than any terrestrial.

What is true of a blackbody?

Its energy peaks at the wavelength determined by its temperature.

From its orbit, we now recognize Pluto as the largest member of the

Kuiper Belt.

The density of the Sun is most similar to which object?

Jupiter

Which planet by itself contains the majority of mass of all the planets?

Jupiter

Which of the following discoveries was NOT made by Voyager 1 or 2?

Jupiter has cloud bands in its upper atmosphere.

How does the heat Jupiter radiates compare to the energy it receives from the Sun?

Jupiter radiates back into space about twice the energy it gets from the Sun.

What evidence do we have that Jupiter must have a substantial solid core under the thick clouds?

Jupiter's disk is less oblate than it should be, if it were only hydrogen and helium.

Which of the following are the Jovian planets?

Jupiter, Saturn, Uranus, and Neptune only

The temperature scale that places zero at the point where all atomic and molecular motion ceases is

Kelvin.

The three laws dealing with the creation of various spectra are due to:

Kirchhoff.

The orbital resonances with Jupiter are shown in the

Kirkwood Gaps.

Which objects in the solar system have been least modified since the formation of the solar system?

Kuiper Belt objects

What arguments are cited for the existence of the Oort Cloud of comets? (SA)

Long-period comets have very large orbits that carry them out tens of thousands of A.U. away from the Sun. Kepler's second law tells us that the comets spend most of their time at these great distances. Because the direction of the orbit and its inclination appear random, all this implies a vast cloud of cometary objects surrounding the solar system; i.e. the Oort Cloud. Then in 2004 came the discovery of huge Sedna, the biggest solar system body found since Pluto; its orbit lies far beyond the Kuiper Belt, so it seems to belong to the Oort Cloud as well.

The two names most associated with the discovery of Pluto are

Lowell and Tombaugh.

The type of asteroid that would be the densest would be type

M.

Our best data about the surface topography of Venus has come from:

Magellan radar data and radar observations of the planet from Earth.

The best present maps of the surface of Venus come from the:

Magellan.

The orbiter that gave us the most detailed maps of Venus to date was:

Magellan.

Which spacecraft gave us our best information about Mercury, until Messenger arrives in 2009?

Mariner 10

Which statement about Mercury is not correct?

Mariner 10 is now dead, but still in orbit about Mercury.

Which of these spacecraft did not go to Jupiter?

Mariner 9

Which of these is not now on the surface of Mars?

Mars Global Surveyor

(SA) Why do oppositions of Mars stir such interest among amateur astronomers?

Mars is small, and most of the time so distant from Earth that amateur telescopes have a problem seeing anything but an orange disk. But when the earth overtakes Mars every 2.2 years, Mars gets close enough to us to appear much larger and to show a good deal of surface features and atmospheric clouds, polar caps, and dust storms.

What makes the view of Mars in the summer of 2003 so spectacular?

Mars was both at perihelion and opposition, creating the perfect viewing conditions from Earth.

Why was the summer of 2003 a fine time for Mars observers?

Mars was closer to us than it has been in over 50,000 years.

Why are Mars' seasons more extreme than those of the earth?

Mars' weather is driven by evaporation from the polar ice in its summer. Mars' orbit is more eccentric than our almost circular one. Mars' seas dried up long ago. Mars' axial tilt is slightly more than our 23.5 degrees. All of these contribute to the huge barometric changes that Mars experiences.

The most striking example of solar variability as the

Maunder Minimum from 1645-1715.

The highest peak on Venus is called:

Maxwell.

In terms of its orbit, which of the terrestrials is oddest?

Mercury

The Mariner 10 spacecraft visited which bodies in the solar system?

Mercury and Venus

How did Mercury's location in the solar system affect its composition?

Mercury is rich in metals because only metallic grains could survive the high temperatures so near the Sun.

Which is the correct size order, from smallest to largest?

Mercury, Mars, Venus

In the atmospheres of the jovian planets, this component increases, systematically, with distance from the Sun

Methane

In the atmospheres of the jovian planets, this component increases, systematically, with distance from the Sun.

Methane

Although the atmospheres of Uranus and Neptune are very similar, the atmosphere of Neptune contains more

Methane.

How is Mimas responsible for the Cassini Division? (SA)

Mimas has an orbital period precisely twice that of matter in the Cassini Division. As such, it exerts a regular tug on particles there, pulling them to an orbit further out. The particles stay in the outer orbit once they collide with other particles and lose excess energy.

Which of the Uranian moons displays the widest range of surface terrains, suggesting some catastrophic disruption?

Miranda

Which moon of Uranus has the strangest terrain? What is a possible explanation for its jumbled appearance? (SA)

Miranda has a strange appearance, with layer, differentiated blocks turned edge on all over its surface in jumbled, haphazard fashion. Perhaps it was broken up by a huge collision with a Kuiper Belt body after it had formed into a sphere, and some of the pieces did not escape, but fell back together in this odd puzzle.

Why are molecular lines more complex than elemental spectral lines?

Molecules can vibrate and rotate as well.

What is thought to have caused the craters on Venus?

Most are volcanic in origin; some are due to meteoritic impacts.

Which statement about the motion of the planets is incorrect?

Most planets move in the Earth's equatorial plane.

Why does the atmosphere of Saturn appear to have only half the helium content of Jupiter?

Much of Saturn's helium has differentiated towards its center.

The NASA orbiter that ultimately landed on the surface of the asteroid Eros was

NEAR Shoemaker.

The Tharsis Bulge on Mars is roughly the size of

North America

Star A and star B have the same temperature, but different luminosities. What can you infer about these two stars?

Nothing can be inferred from the information given.

What is oblateness, and what does it tell us about Jupiter's interior? (SA)

Oblateness is the degree to which the planet's rotation causes its equator to bulge and poles to flatten. In Jupiter's case, it is more round than it would be, spinning as rapidly as it does, if it were made only of hydrogen and helium gas; it must have a more solid rocky core deep underneath the fluid clouds.

The largest shield volcano yet discovered is:

Olympus Mons on Mars.

Long period comets are thought to reside mainly in the

Oort Cloud.

When it was determined that Sedna, the largest body in the Solar System to be discovered since Pluto, has a perihelion distance that is three times further out than Pluto and such an eccentric orbit that it has a period of thousands of years, it was placed in the

Oort Cloud.

Describe the consequences of orbital resonances between the moons of Saturn and the particles that make up that planet's ring system. (SA)

Particles that would have orbital periods which are integral fractions of lunar orbits are constantly pulled out of these orbits and into elliptical orbits. Through particle collisions, these orbits become circular again. Thus orbital resonances are effective in moving ring particles out of certain orbits and into others.

The NASA lander which deployed the first rover, Sojourner, in 1997 was:

Pathfinder.

Why were the mass and density of Pluto unknown until Charon was found? (SA)

Pluto is so distant that its disk was not resolved well, and it had no discernable gravitational influence on Uranus and Neptune (Lowell's prediction was just luck). But Charon's orbit let us find the mass of both objects, and the series of eclipses allowed us to calculate the sizes of both bodies with great accuracy.

(SA) In the proton-proton cycle, two positrons are produced. What are they similar to, and how are the different? What happens to them?

Positrons are the antiparticle to the electron. They are like the electron in mass but positive in charge. When positrons inevitably meet electrons, both particle and antiparticle are annihilated and energy is given off.

Which statement about extrasolar planets found to date is true?

Some are so close to their stars that their periods are just a few days.

Why did a major planet not form out in the Kuiper Belt?

Some may have, but they have since migrated to orbits nearer the Sun.

Star A and star B have the same temperature, but star A is 5 times bigger than star B. Which statement below is correct?

Star A and star B have the same color, but star A is brighter.

Star A has a temperature 3 times that of star B. Both star A and star B are the same physical size. Which statement about star A and star B below is correct?

Star A is bluer and brighter than star B.

Star A has a temperature 1/2 that of star B, but star A is 5 times bigger than star B. Which statement below is correct?

Star A is redder and brighter than star B.

Star A has a temperature 1/2 that of star B, but star A is 3 times bigger than star B. Which statement below is correct?

Star A is redder and dimmer than star B.

Star A has a temperature 1/4 that of star B. Both star A and star B are the same physical size. Which statement below is correct?

Star A is redder and dimmer than star B.

Star A and star B have the same temperature, but star B is more luminous than star A. What can you infer about these two stars?

Star B must be bigger.

What is it about the Sun's corona that astronomers don't understand?

The corona is much hotter than layers of the Sun that are closer to the solar interior.

What is true about solar system densities?

The denser planets lie closer to the Sun.

In light of modern solar system theory, why do the orbits of the planets all lie in the same plane?

The early solar nebula flattened into a disk.

(SA) Explain the stage in which the solar system formed pretty much in a plane.

The flat shape of the solar system is explained by the contraction of a slowly spinning cloud in the solar nebula theory.

What is the origin of the jovian moons?

The four Galilean moons formed with Jupiter, most others were later captures.

When Voyager 2 was routed to fly by Saturn, it was originally the plan to have the satellite fly through the Cassini gap. Why would this have been a bad idea?

The gaps in Saturn's ring system (including the Cassini gap) are not actually empty space, rather they are an area of low density in the rings.

(SA) What are the chemical and physical properties of the solar system that any theory of its origin must explain?

The inner planets have high densities, moderate atmospheres, and a mostly rocky composition. The outer planets have low densities, thick atmospheres, and a composition of mostly hydrogen and helium. The asteroids are composed of primitive, unevolved material unlike planets and the comets are icy objects that have also remained unchanged since the formation of the solar system.

Why is Mars red?

The iron in the surface rocks have been oxidized over time.

Why do scientists think Titan has an atmosphere while the large moons of Jupiter (Ganymede, Callisto, Europa and Io) do not?

The jovian satellites never formed atmospheres because the solar nebula was too hot there.

(SA) Compare the days, seasons, and years of Mars and Earth.

The lengths of the days are very similar, with Mars being 40 minutes longer. The axial tilts are also almost identical, with Mars tilted only .5 degrees more. The year, with Mars' much larger orbit, is over twice as long as ours, however.

(SA) How can Mars, a planet with so little atmosphere, have so much wind?

The major component of Mars' atmosphere, carbon dioxide, freezes out as dry ice every winter, forming a huge but very thin polar cap. But in the opposite hemisphere, that cap is subliming back into the atmosphere, creating a high pressure area above it. With the changing seasons, the atmosphere "flip-flops" from pole to pole, with great barometric pressure changes and hurricane force winds and dust storms observable from earth.

What factor caused different planets to form out of different types of material?

The variation in temperature throughout the solar nebula; the higher the temperature, the lower the percentage of light elements in the forming planet.

In what ways do the magnetic fields of both Uranus and Neptune defy the conventional Dynamo Theory for planetary magnetic fields? (SA)

The planet's rotation, as the word dynamo implies, is paramount in generating the magnetic field, so the field should align itself with the rotational axis; in other words, the N needle on a compass should really point north. For Saturn, it is fine, but at Earth and Jupiter, the field is off by about 10 degrees. However, for Uranus this magnetic tilt is 59 degrees, and even for Neptune it is 47 degrees off. Also, the core of the planet should contain the electrically conductive fluid that generates the field, but for both green giants, the fields do not pass anywhere close to this core.

Why is the southern hemisphere of Mars believed to be older than the northern?

The southern hemisphere is more heavily cratered.

The Galileo mission put a spacecraft into orbit around Jupiter. Which statement about that spacecraft is true?

The spacecraft's probe measured windspeeds in Jupiter's atmosphere.

(SA) Explain what the granulation of the solar surface is related to.

The surface of the Sun is highly mottled or granulated. Each granule is about 1,000 km across. The granulation is produced by the convection (boiling) of the Sun's gases. Each granule is the top of a convection cell that is welling up.

Name two ways the magnetic fields of Uranus and Neptune defy the normal behavior of planetary magnetic fields. (SA)

Their fields are tilted very far off the rotation axes of both planets, most other planets have fields within 10 degrees of their poles. Neither field goes directly through the core of its planet, while all other fields seem to originate in the cores of their planets.

While observing the Sun, you note a large number of sunspots. What can you conclude?

There are likely to be an above average number of flares and prominences.

What are some of the properties of objects in the solar system that a theory of its origin DOES NOT need to account for? Explain. (SA)

There are many answers to this: Mercury's spin-orbit coupling, Venus' runaway greenhouse effect, the Moon's synchronous rotation, the emergence of life on Earth and its absence on Mars, the Kirkwood gaps in the asteroid belt, and the rings and atmospheric appearance of the outer planets.

(SA) For what reasons do we consider the planets of the solar system to be of two fundamentally different types?

There are multiple reasons we consider the planets of the solar system to be of two fundamentally different types. The two types of planets we divide our solar system into are: terrestrial planets and jovian planets. The terrestrial planets have low magnetic fields, small number of moons (if any), and are composed of heavier elements like iron. The jovian planets have very strong magnetic fields, a fairly large number of moons, and are composed of lighter elements like hydrogen and helium. These are the basic reasons as to why we categorize our planets into two different types of planets.

Which statement is true of Venus' surface?

There are two continent sized uplands.

Neptune's moon Triton appears to have a nearly uncratered surface. Explain. (SA)

There has been a large amount of surface activity that has obliterated the craters from much of Triton's surface. These are fissures, nitrogen geysers, and large frozen water ice lakes that are indicative of this activity. This probably is generated by the tidal stresses of its retrograde orbit close to Neptune.

What did the Voyager mission discover about the main rings of Saturn?

They are composed of tens of thousands of narrow ringlets.

Sunspots are dark splotches on the Sun. Which statement is true?

They are extremely hot, but cooler than the surrounding areas of the Sun.

Which statement gives the relationship between the waves in the electric and magnetic fields in an electromagnetic wave?

They are in phase but perpendicular to each other in space.

Which statement about Jupiter's rings is false?

They are made of ice, like Saturn's.

Why are Saturn's rings so noticeable?

They are made of lots of fresh, bright icy particles from a recent breakup.

What could explain the darker appearance of moons and rings in the outer solar system?

They are made of small, sooty particles and radiation darkening with loss of volatile bright ices.

What are the Kirkwood Gaps? What role does Jupiter play? (SA)

They are regions within the asteroid belt where resonances with Jupiter, particularly at the 2:1 region, have cleared asteroids from that period and distance.

Why are the jovian planets so large?

They formed from the largest protoplanets which swept gas from the solar nebula.

What is the defining property of the Trojan asteroids?

They have orbits at the distance of Jupiter and 60 degrees ahead of or behind it.

Why is it reasonable to conclude that the internal structure and evolution of Venus are basically Earthlike?

They have similar masses and sizes.

The most striking valley in the solar system is:

Valles Marineris on Mars.

How did scientists use Titan to guide Cassini on a tour of Saturn's moon system? (SA)

Titan was used to give gravitational assists to increase and decrease the semi-major axis of the probe's orbit. When Cassini passes Titan inside its orbit of Saturn, Cassini's orbital semi-major axis is decreased. When Cassini passes Titan outside its orbit of Saturn, Cassini's orbital semi-major axis is increased. Using this, Cassini's controllers are able to guide the spacecraft on a tour of Saturn's moon system even though the spacecraft doesn't have much of its own power.

While Cassini was launched toward Saturn in 2004, its Huygens probe in 2005 went to:

Titan.

Why do scientists think the Cassini spacecraft did not observe "spokes" on the rings during the first year of its visit with Saturn?

To see the "spokes", a particular alignment of the rings with the Sun is necessary and it took one year for that alignment to reoccur.

Pluto is most similar to

Triton.

Which of these landed on Venus?

Venera 7

Adams and Leverrier both predicted the position of Neptune, based on its effects on

Uranus

Adams and Leverrier both predicted the position of Neptune, based on its effects on:

Uranus

Adams and Leverrier predicted the position of Neptune, based on its perturbations of

Uranus

At which planet can the pole remain in darkness for 42 years, then have 42 years of constant daylight?

Uranus

In terms of axial tilt, which of the jovians shows us the largest inclination?

Uranus

The planet whose pole was facing the Sun when Voyager 2 approached in 1986 was

Uranus

William Herschel thought he had found a comet when he spotted the green disk of

Uranus

The magnetic field tilts of which two bodies are the most unusual?

Uranus and Neptune

William Herschel thought he had found a comet when he spotted the green disk of:

Uranus.

Describe the interaction between Jupiter and Comet Shoemaker-Levy 9. (SA)

When the comet passed close to Jupiter in 1992, gravitational tidal forces tore the nucleus apart, leaving it in fragments. On it's approach in 1994 it struck the planet. Vibrations in the interior and atmospheric effects lasted for days. Huge fireballs were observed from Earth. Debris from the comet spread completely around the planet, taking years to settle out.

How does the discovery of a comet typically differ from that of an asteroid? (SA)

While both bodies are in motion, and thus noted as streaks on time exposure photos and CCD images, comets typically do not become visible until they approach the Sun and develop a coma, so their images are often fuzzy. Many amateur discoveries of comets depend on this fuzzy appearance in telescopes.

The hottest objects with temperatures in the millions of degrees Kelvin, give off most of their radiation in which part of the electromagnetic spectrum?

X-ray

Which of the following type of electromagnetic radiation has the highest energy?

X-ray

There are no X-ray telescopes on Earth because

X-rays don't penetrate Earth's atmosphere

X-ray telescopes are located in orbit around the Earth because

X-rays don't reach the surface of Earth.

The most detailed look we've had of an asteroid comes from

spacecraft sent to an asteroid.

As the solar nebula contracts it

spins faster due to conservation of angular momentum.

How long does the sunspot cycle last, on average?

about 11 years

The synodic period of Venus is about how many Earth years?

about 3.5 years

At the surface of Saturn's atmosphere the strength of the magnetic field is

about the same as Earth's magnetic field at its surface.

Where is Jupiter's ring located?

above Jupiter's cloud tops and inside the orbit of its inner-most moon

The rings of Uranus and Neptune are found

above their equators.

The rings of Uranus and Neptune are found:

above their equators.

The Fraunhofer lines in the solar spectrum are actually:

absorption lines due to the thin outer layer above the photosphere.

Magellan did not find which of these on Venus?

actual volcanic eruptions in progress

To have a negative ion, you must have:

added an electron to the outer electron shell.

The jovian planets

all have rings around their equators.

A successful theory of the formation of the solar system must explain

all observed properties of the solar system.

What information about an astronomical object can be determined by observing its spectrum?

all of the these: its chemical composition its radial motion whether it has a strong magnetic field its temperature

The white zones of Jupiter are probably made of:

ammonia ice.

What is spectroscopy?

an analysis of the way in which atoms absorb and emit light

In the proton-proton cycle, the positron is

an anti-electron.

As the solar nebula contracts due to gravitation, the cloud

spins faster.

What did the Huygens and Cassini probes find on the surface of Titan?

an ocean of some unknown liquid and methane lakes

Planetary orbits

are almost circular, with low eccentricities.

The body which wiped out the dinosaurs was about

as big as one of Mars' moons.

Before it arrived in orbit about Eros, the NEAR spacecraft also flew past

asteroid Mathilde.

Which of the following is not icy in composition?

asteroids

Asteroid 2004 FH passed within a tenth of the Earth-Moon distance in March 2004. When its period was found to be about nine months, it was classified as a(n)

aten asteroid.

An emission spectrum can be used to identify a(n)

atom

The shepherd moons keep the ring particles in their rings by

attracting the ring particles, causing them to speed up or slow down.

What do our magnetic field and Jupiter's share?

auroral displays in the polar regions

The tail of a comet always points

away from the Sun and becomes longest and brightest at perihelion.

The planet Uranus is

barely visible with the naked eye.

Why does Mars appear fainter than Venus, as seen from Earth?

because it is smaller, farther away and less reflective

What is the name used to describe the dark bands encircling Jupiter?

belts

Most asteroids are found:

between the orbits of Mars and Jupiter.

The Kuiper Belt is found where in the solar system?

beyond the orbit of Neptune

If a light source is approaching you at a speed very close to the speed of light, it will appear

bluer than it is.

How was the rotation rate of Jupiter's core determined?

by radio observations of Jupiter's rapidly spinning magnetosphere

Electromagnetic radiation

can behave both as a wave and as a particle.

Which of the following is NOT a property of neutrinos?

cannot interact at all with normal matter

What is the main constituent of the atmosphere of Venus?

carbon dioxide

The main constituent of the Martian atmosphere is

carbon dioxide.

If water caused the huge outflow channels on Mars, what was the most likely process that formed them?

catastrophic but rare flooding

A gravitational "sling-shot":

changes the speed and direction of a spacecraft nearing a massive planet.

Because the atmosphere of Venus is so dense,

clouds cannot form.

Sunspots

come in pairs, representing the north and south magnetic fields.

Which of the following have an icy composition?

comets

By what mechanism does solar energy reach the Sun's photosphere from the layer just underneath it?

convection

Saturn's bands, oval storm systems, and turbulent flow patterns are powered by:

convective motion and rapid rotation.

What phase of planet formation caused the jovian planets to form?

core-accretion

With rapid collapse from icy planetesimals, what theory would have the jovians growing quickly into giants?

core-accretion

The largest volcanic structures on Venus are called:

coronae.

From where does most of the solar wind flow?

coronal holes

The solar winds blow outward from

coronal holes.

Alternating zones of rising and sinking gas in Jupiter's atmosphere

create light and dark bands.

The Apollo and Aten asteroids have orbits that

cross the orbit of Earth at perihelion.

The Amor asteroids have orbits that

cross the orbit of Mars, but not Earth, at perihelion.

What are comets made of?

dark colored complex hydrocarbons silicates and rocky dust metallic dust particles methane, ammonia, and water ice all of the above

According to Wein's Law, if the surface temperature is increased by a factor of 2, its peak wavelength will

decrease by a factor of 2.

What is the probable source of the day-to-day variations in Jupiter's belts and zones?

differential rotation and the underlying zonal flow

Which of these were observed from Earth, prior to spacecraft missions to Mars?

dust storms capable of covering the entire planet seasonal changes in the polar caps Both A and C are correct.

Carbonaceous Chondrites are believed to come from

the crust of a differentiated C type asteroid, now broken up.

The asymmetrical surface markings on some of Saturn's moons are probably due to:

in most cases, the moons are tidally locked by Saturn's gravity into synchronous rotation.

Meteor shower debris is believed to come from

the disintegration of a short period comet over many returns to the Sun.

The plane in which almost all planets orbit the sun is called the:

ecliptic.

What natural barrier tried to prevent two protons from combining?

electromagnetic repulsion

In space, positive ions are the result of:

electrons being stripped off the outer electron shell for hot atoms.

The particles which enter into chemical reactions are the atom's:

electrons.

The numbers of sunspots and their activity peak about every:

eleven years.

The outflow channels on Mars indicate a flood period in the history of Mars. During this time, based on the width and depth of the remaining riverbed, it is thought that the flow rate must have been

enormous, as much as 100 times the flow rate of the Amazon River.

Saturn's rings are edge-on and vanish when it is at:

equinox.

Our understanding of the solar system has come in a way that can best be described as:

explosive, with us learning more in the past few decades than in all previous history.

As a rotating gas cloud contracts, it spins

faster due to conservation of angular momentum.

Compared to Jupiter, the motions observed in Saturn's atmosphere are

faster with fewer zone-belt alternations.

The first hint of the role of asteroids in extinction of the dinosaurs came from

finding a layer of worldwide iridium enriched dust.

If you could find a bathtub big enough for Saturn, the planet would:

float.

Colors appear different to us because of their photons' different:

frequencies.

A wave's velocity is the product of the

frequency times the wavelength of the wave.

The fact that Venus' atmosphere contains carbon dioxide was discovered:

in early spectroscopic studies.

A moon that goes inside the Roche Limit will

get heated by the strong magnetic fields.

Which of these are not associated with the active Sun?

granulation

Visible sunspots lie in the

granulation in the photosphere.

The pattern of rising hot gas cells all over the photosphere is called:

granulation.

Hydrostatic equilibrium in our Sun is the balance between

gravitation and pressure.

Allowing for more time for the jovians to form, what theory would rely more on gas and less on solid materials?

gravitational instability

The seasonal changes on Mars create:

great changes in the barometric pressure as the atmosphere freezes and sublimes. remarkable changes in size of the two dry ice polar caps. huge dust storms that can enshroud the planet's disk. changes in the dark features noted from Earth by telescopes long ago. All of these are correct.

What is the process of accretion?

growth of an object by the accumulation of matter

Unlike the other jovian planets, Uranus

has no internal energy source

According to the photoelectric effect in order to release electrons from a solid, the light incident upon it must

have a short wavelength

Rhea, Saturn's second largest moon, might best be described as:

having a very reflective, icy surface that is heavily cratered.

The element first found in the Sun's spectrum, then on Earth 30 years later, is

helium

What causes the changing dark and light features visible on the Martian surface from Earth?

highly cratered and eroded areas that are frequently covered and uncovered by dust

In comparing our own solar system with others found to date, we find:

hot Jupiters, even closer to their stars than Mercury is to our Sun. multiple planets are found in some systems. jovians often lie much closer to their suns than ours do. that most orbits are less circular than planets around our Sun. all of the above

Dust is an important part of the nebular theory of solar system formation because dust is needed to explain

how the inner planets came to be rocky bodies.

The atmosphere of Saturn is composed mostly of:

hydrogen and helium.

The most abundant element in Saturn's atmosphere is

hydrogen.

The "wispy terrain" on Rhea was revealed by the Cassini spacecraft to be

ice cliffs created by tectonic fractures.

The Kuiper Belt is an "outer asteroid belt" consisting of what types of solar system bodies?

icy cometlike bodies

Small deviations in a planet's orbital motion

imply the nearby presence of a massive body.

What is the source of Jupiter's nonthermal radio radiation?

metallic hydrogen swirling in the planet's interior

Which of the following objects would be found on the Moon's surface?

meteorites

Which of the following gives direct information about the age of the solar system?

meteorites from asteroidal debris

Uranus and Neptune appear bluish in color because

methane gas in their atmospheres absorbs red light well.

Pluto's density is most similar to

moons of the jovian planets.

Shepherd satellites are defined as:

moons that confine a narrow ring.

In order to determine the mass of a planet by applying Newton's laws of motion and gravity, the planet must have

moons.

Compared to Jupiter, Saturn's atmosphere is

more calm with fewer disturbances or storms.

What would Jupiter have needed to have become a star?

more mass

The particle which adds mass but no charge to the atomic nucleus is the:

neutron.

The atmosphere of Titan is composed mostly of:

nitrogen.

The light from an object moving tangentially (to your left or right) will exhibit

no shift.

The detection of most extra-solar planets is done by

noting Doppler shifts due to their gravitational influence on their star's motion.

Most of the extrasolar planets found so far were detected by

noting the Doppler shifts of the star as the planet orbits it from side to side.

What part of a comet has only been seen by a space probe?

nucleus

The rings of Neptune:

number five, with three narrow, two more diffuse. often appear as clumpy ring arcs, rather than complete and symmetrical. were confirmed by the Voyager 2 in 1989. all lie within Neptune's Roche Limit. All of these are correct.

The masses of Neptune and Uranus were first determined by

observations of the motions of their satellites.

In Bohr's model of the atom, electrons

only make transitions between orbitals of specific energies.

The planet Neptune is

only visible with a small telescope or binoculars.

Mars is best viewed from Earth when it is at

opposition.

Comparing the clouds of Earth and Venus, we find that:

ours lie in the troposphere, within 10 kilometer of our surface, but Venus has a higher troposphere, with its clouds about 40 kilometers high.

How were the rings of Uranus discovered?

photometric observations of the occultation of a star made from Earth

The light we see from the Sun comes from which layer?

photosphere

In composition and density, the asteroids most resemble:

pieces of terrestrial planets.

Objects that are in a 3:2 orbital resonance with Neptune are called

plutinos.

Which of the characteristics below describes the terrestrial planets?

possessing weak magnetic fields

The solar constant is a measure of

the energy received by the Sun at the location of Earth.

What are Saturn's rings?

small icy particles moving in orbit around Saturn

Because of its slow rotation period, Venus:

presents the same side to Earth at each closest approach.

Loops of glowing hydrogen seen hanging over the solar limb during totality are:

prominences.

A hydrogen atom consists of an electron and a(n)

proton.

In the atom, which particles gives the element its identify (atomic number)?

protons

The surface of Venus can be observed with:

radar observations from Arecibo.

The Doppler Effect is a phenomenon that allows one to measure an object's

radial motion.

What two energy transport mechanisms, in order from outside the core to the surface, is found in the Sun?

radiative diffusion, convection

From inside out, which is in the correct order for the structure of the Sun?

radiative zone, convective zone, chromosphere

The Earth's ionosphere partially blocks which form of electromagnetic radiation?

radio

Which of the following type of electromagnetic radiation has the lowest energy?

radio

Since the difference in energy between the different rotational states in a molecule is very small, many molecular lines can be observed with:

radio or microwave telescopes.

There are no radio telescopes in space because

radio waves penetrate Earth's atmosphere so there is no need to put one in space

Of all the forms of electromagnetic radiation, the one with the lowest frequency is

radio waves.

Electromagnetic radiation with a wavelength of 700 nm would be:

red light.

When we glimpse the chromosphere at the start and end of totality, its color is

red, due to ionized hydrogen at lower pressure.

When the chromosphere can be seen during a solar eclipse, it appears:

red.

The belts of Jupiter are best described as follows:

regions of downward moving material and low pressure.

Valles Marineris is the most striking example of a(n)

rift valley.

Through radar observations it was found that Venus'

rotation on its axis is retrograde.

Studying the magnetospheres of the jovians has allowed us to measure their

rotation rates.

Compared with the other jovian planets, Neptune is

small with features similar to Jupiter.

The Roche limit is the point at which

the external tidal forces on an object become greater than the internal forces that hold it together.

Saturn's rings are widest open, doubling the planet's brightness, when it is at:

solstice.

Various observations suggest there may be recent or even continuing volcanic activity on Venus. Which of the following has NOT been observed?

spacecraft detection over a period of days of flowing lava on Venus

What aspects of the planets orbits are nearly the same for most planets?

shape and tilt from the ecliptic

Maxwell Mons on Venus is a huge:

shield volcano.

Olympus Mons and Maxwell Mons are both

shield volcanoes.

According to the Solar Nebula theory, planets

should be a common result of star formation.

In strength, the magnetic fields of Uranus and Neptune are:

similar, with both about 100 times stronger than our own.

Suppose a large flare is detected optically. How long until radio interference arrives?

simultaneously

Earth and Venus are often called sister planets; in which ways are they most alike?

size, density, and surface gravity

The difference between a meteoroid and an asteroid is the object's

size.

The Kuiper Belt objects have orbits that

stay out just beyond Neptune and close to the ecliptic.

The Trojan asteroids have orbits that

stay sixty degrees ahead of or behind Jupiter.

That the Tharsis region on Mars has so few craters

suggests it is the youngest region on the planet.

What is the major component of Io's volcanic flows?

sulfur and its compounds

What is the composition of the clouds of Venus?

sulfur and sulfuric acid droplets

Venus' full phase occurs when Venus is at:

superior conjunction.

Venus' rotation:

takes longer than its orbit around the Sun.

The wavelength at which a blackbody radiates most depends on its

temperature.

In composition, asteroids and meteoroids are most like

terrestrial planets.

Stefan's Law says:

that if the Sun's temperature were doubled, it would give off 16X more energy.

The unique feature of Neptune is

that its atmosphere rotates more slowly than its interior

One of the most unexpected aspects of Mars' atmosphere is

that its troposphere changes altitude.

Hubble Space Telescope photos have shown us

the Great Dark Spot of Neptune vanished in 1995. the rings of Uranus show up better in infrared than in visible light. Uranus weather has produced more prominent patterns as equinox approaches. Neptune still has more activity than Uranus, despite its distance from the Sun. All of the above are correct.

Hubble Space Telescope photos have shown us:

the Great Dark Spot of Neptune vanished in 1995. the rings of Uranus show up better in infrared than in visible light. Uranus weather has produced more prominent patterns as equinox approaches. Neptune still has more activity than Uranus, despite its distance from the Sun. All of the above.

Our most detailed maps of Venus come from:

the Magellan spaceprobe.

In composition and mass and density, Jupiter is most like:

the Sun.

The difference between the Grand Canyon and the Valles Marineris is

the Valles Marineris has craters in and around it. the Grand Canyon was formed by water. the Valles Marineris has tectonic features surrounding it. the Valles Marineris is much larger than the Grand Canyon. all of the above

To see the Sun's hot corona (a temperature of 1,000,000 K, which part of the electromagnetic spectrum should one observe?

the X-ray

"Catastrophes" are NOT needed to explain

the asteroid belt.

Saturn's cloud surface appears more uniform than Jupiter's because

the cloud layers are thicker, allowing fewer holes to see the colorful layers.

A surprise from the Pioneer Venus photos was that:

the clouds rotate around the planet in only four days, very unlike the slow surface rotation.

Iron meteorites are believed to come from

the core of a dense M-type asteroid, now broken up.

The reason the rings of Saturn exist is because:

the ring material lies within the Roche limit of Saturn.

Mercury's most unusual orbital feature, as compared to the other planets, is

the shape of its orbit.

What might have made the original solar nebula begin to contract?

the shock wave from a nearby exploding star

Jupiter gives back into space twice the energy it gets from the distant Sun. Where is this energy coming from, for the most part?

the slow escape of gravitational energy left from its formation

What is the source of Jupiter's excess energy?

the slow escape of gravitational energy released during the planet's formation

The relatively small number of impact craters and the near absence of small craters on the surface of Venus is thought to be a result of:

the soft and resilient nature of the Venusian surface.

Where do the names for the moons of Mars (Phobos and Deimos) come from?

the sons of Ares and Aphrodite

The largest difference between Mars' northern and southern hemispheres is that:

the southern appears older, with more impact craters.

The Oort Cloud is thought to be

the spherical cloud of comets and some larger icy bodies surrounding the outer solar system.

The primary source of the Sun's energy is

the strong force fusing hydrogen into helium.

The planet's orbital period is:

the time it takes to return to the same location in the sky, relative to the Sun.

The luminosity of the Sun is a measure of

the total energy emitted by the Sun in all directions.

Very hot, young stars, like those in Messier 2 emit most of their light in which part of the electromagnetic spectrum?

the ultraviolet

Stars like our Sun emit most of their light in which part of the electromagnetic spectrum?

the visible

What does the phenomenon of diffraction demonstrate?

the wave nature of light

What does the phenomenon of interference demonstrate?

the wave nature of light

Neptune and Uranus have a bluish tint because

their atmospheres contain methane, which absorbs red light

Neptune and Uranus have a bluish tint because:

their atmospheres contain methane, which absorbs red light.

The rotation periods of Venus, Jupiter, Saturn, Uranus and Neptune are difficult to determine because

their surface features are obscured by their atmospheres.

Masses of the planets are easiest to determine if:

they have natural satellites whose motions can be precisely measured.

Meteorites are valuable to astronomers because

they may provide evidence about the process in which the solar system was born.

Venus and Mars probably evolved differently from Earth because:

they orbit at different distances from the Sun.

What is thought to be the cause of Io's volcanoes?

tidal stresses from both Jupiter and Europa

What is the goal of comparative planetology?

to determine the origin and evolution of the solar system

The area in the Sun's atmosphere located above the chromosphere (1500-10,000 km) where the temperature rises dramatically is called the

transition zone.

As the Sun rotates, an individual sunspot can be tracked across its face. From eastern to western limb, this takes about

two weeks.

Which form of electromagnetic radiation would be blocked in the stratosphere by ozone?

ultraviolet

Which of these is constant for ALL types of electromagnetic radiation in a vacuum?

velocity

The visible color of electromagnetic radiation that has the shortest wavelength is

violet.

Which type of radiation can be observed well from Earth's surface?

visible

The two forms of electromagnetic radiation that penetrate the atmosphere best are:

visible and radio waves.

Most of the dark regions on Mars visible from Earth are

volcanic planes like the lunar maria.

The average density of each planet in the solar system is determined by taking its mass and dividing that by its

volume

When we are lucky enough to see an extra-solar planet transit its star

we can by the drop in light find the planet's size, mass, and density.