Astronomy 109 Ch. 13

What was the first planet discovered by mathematical prediction? A. Neptune B. Uranus C. Vulcan D. Pluto E. None of these

A. Neptune

Compared with Uranus, the planet Neptune is A. roughly the same size. B. much smaller. C. much larger. D. tilted on its side.

A. roughly the same size.

Radiation darkening is a likely explanation of: A. why Uranus' moons are less reflective than Saturn's. B. why Uranus' rings are so much fainter than Saturn's. C. the lack of distinct, visible bands in Uranus' atmosphere. D. Uranus' extreme axial tilt. E. the tilt of Uranus' magnetic field relative to the rotation axis.

A. why Uranus' moons are less reflective than Saturn's.

What has created Uranus's magnetic field? A. A layer of metallic hydrogen B. A layer of conducting water C. The presence of heavy metals in its core D. An imprint of its primordial magnetic field

B. A layer of conducting water

Which statement about the magnetic fields of Uranus and Neptune is FALSE? A. Uranus' field is tilted 60 degrees off its already tilted rotational axis. B. Both pass directly through the cores of their planets, like all other fields. C. Neptune's field is tilted 47 degrees to its more conventional rotational axis. D. Both may have ammonia water replacing the liquid metallic hydrogen. E. Neither fits the Dynamo model very well.

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

Which of these is true about the seasons of Uranus? A. There are no seasons at the poles. B. Its strange tilt produces extreme seasonal variations, especially at the poles. C. At the Uranian equator, the Sun would pass overhead every sixteen hours. D. With a tilt of 29 degrees, they are not that different from our solstices and equinoxes. E. At the Uranian pole the Sun sets every 16 hours during the summer and winter.

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

Which planet had the Great Dark Spot in 1989, but had lost it by 1995? A. Jupiter B. Neptune C. Mars D. Saturn E. Uranus

B. Neptune

The extreme seasonal variations on Uranus over the course of a complete orbit around the Sun are due to which of the following? A. Variations in the Sun's intensity B. The 98° tilt of its rotation axis to its orbital plane C. Variations in its rotational rate about its axis D. Periodic shadowing of sunlight by the other jovian planets E. Variations in its distance from the Sun

B. The 98° tilt of its rotation axis to its orbital plane

Why are the moons of Uranus and Neptune so dark? A. They are covered with extensive dried lava beds. B. They are subject to radiation darkening. C. They are covered in soot. D. They are too far from the Sun to receive and reflect much light.

B. They are subject to radiation darkening.

The planet Uranus is: A. only visible with a large, high quality telescope. B. barely visible with the naked eye. C. only visible with a space-based telescope. D. only visible with a small telescope or binoculars. E. easily visible with the naked eye.

B. barely visible with the naked eye.

What is erupting out of the geysers on Triton? A. liquid hydrogen with dark helium ash B. liquid nitrogen with carbon grit C. liquid water with basalt D. liquid carbon dioxide with graphite E. liquid methane with a dark hydrocarbon slush

B. liquid nitrogen with carbon grit

The unique feature of Neptune is: A. its banded cloud surface. B. that its atmosphere rotates more slowly than its interior. C. that it has no ring system. D. that its rotational axis is tilted 98 degrees. E. that it rotates in a retrograde sense.

B. that its atmosphere rotates more slowly than its interior.

Why did astronomers suspect there was an eighth planet beyond Uranus? A. Herschel actually saw two objects when he discovered Uranus, but he was uncertain about the fainter of the two. B. It had been glimpsed on several photographs. C. Irregularities in the motion of Uranus suggested that gravity from another planet was affecting it. D. After the seventh planet was found, it was natural to assume there would be more.

C. Irregularities in the motion of Uranus suggested that gravity from another planet was affecting it.

Why is Neptune bluer than Uranus? A. It has less ammonia. B. It has more helium. C. It has more methane. D. It has more water ice.

C. It has more methane.

Although the atmospheres of Uranus and Neptune are very similar, the atmosphere of Neptune contains more: A. Hydrogen. B. Helium. C. Methane. D. Ammonia. E. Nitrogen.

C. Methane

In the atmospheres of the jovian planets, this component increases, systematically, with distance from the Sun. A. Hydrogen B. Helium C. Methane D. Ammonia E. Nitrogen

C. Methane

What is the most significant difference between the Great Dark Spot of Neptune and the Great Red Spot of Jupiter? A. The Great Dark Spot is not a large storm system but rather a sort of hole in the atmosphere. B. The clouds travel in opposite directions. C. The Great Dark Spot has disappeared, whereas the Great Red Spot has been seen for hundreds of years. D. Relative to its planet's size, the Great Dark Spot is much larger than the Great Red Spot.

C. The Great Dark Spot has disappeared, whereas the Great Red Spot has been seen for hundreds of years.

All but one of the following properties of Uranus's rings makes them different from the rings of Saturn. Which property is the same for both planets? A. They are very dark. B. They are widely spaced. C. They are very thin. D. They are very narrow.

C. They are very thin.

In terms of axial tilt, which of the jovians shows us the largest inclination? A. Jupiter B. Neptune C. Uranus D. Saturn E. Pluto

C. Uranus

On which planet can the pole remain in darkness for 42 years, and then have 42 years of constant daylight? A. Pluto B. Jupiter C. Uranus D. Saturn E. Neptune

C. Uranus

Which planet has the greatest tilt of its rotation axis? A. Neptune B. Jupiter C. Uranus D. Saturn

C. Uranus

The rings of Uranus and Neptune are found: A. in the ecliptic plane. B. outside the Roche limit. C. above their equators. D. by the Hubble Space Telescope. E. All of the above.

C. above the equators.

Unlike the other jovian planets, Uranus: A. has only a few satellites. B. rotates slowly. C. has no internal energy source. D. has a featureless atmosphere. E. has no ring system.

C. has no internal energy source.

How were the rings of Uranus discovered? A. by William Herschel, while he also found the two largest moons B. by Percival Lowell, who observed two "bumps" on either side of Uranus C. photometric observations of the occultation of a star made from Earth D. by the Hubble Space Telescope in the infrared E. by Voyager 2 when it passed by Uranus in 1986

C. photometric observations of the occultation of a star made from Earth

Studying the magnetospheres of the jovians has allowed us to measure their: A. orbital period. B. gravity. C. rotation rates. D. orbital radius. E. ring system diameters.

C. rotation rates

In the atmospheres of the jovian planets, this component decreases, systematically, with distance from the Sun. A. Hydrogen B. Helium C. Methane D. Ammonia E. Nitrogen

D. Ammonia

Unlike the atmospheres of Jupiter and Saturn, Uranus and Neptune have almost no: A. Hydrogen. B. Helium. C. Methane. D. Ammonia. E. Nitrogen.

D. Ammonia

As a percentage of their total volumes, how do the cores of Uranus and Neptune compare with those of Saturn and Jupiter? A. Their cores are much smaller than those of Jupiter and Saturn. B. Scientists are still not sure of the exact sizes of the cores of any of the jovian planets. C. Their cores are exactly the same size as Jupiter's and Saturn's. D. Their cores are larger than those of Jupiter and Saturn.

D. Their cores are larger than those of Jupiter and Saturn.

In 1781, Uranus was the first new planet to be discovered in how many years? A. 16 B. 127 C. 48 D. more than 2000

D. more than 2000

In addition to Saturn's Titan, which other moon has a nitrogen atmosphere? A. Jupiter's Europa B. Jupiter's Ganymede C. Pluto's Charon D. Uranus' Titania E. Neptune's Triton

E. Neptune's Triton

Uranus' large axial tilt is thought to be the result of: A. the same orbital irregularities that led to the discovery of Neptune. B. a single collision or impact event early in the solar system's history. C. the captures of one or more of Uranus' moons. D. multiple catastrophic events, such as glancing collisions. E. giant planet migration.

D. multiple catastrophic events, such as glancing collisions

Neptune and Uranus have a bluish tint because: A. they are far away and distance makes objects appear bluish. B. their atmospheres contain hydrogen and helium. C. ammonia ice reflects blue light better than any other color. D. their atmospheres contain methane, which absorbs red light. E. at their distances, the Sun appears blue, the red absorbed by dust in the ecliptic.

D. their atmospheres contain methane, which absorbs red light.

The time between equinoxes on Uranus is about: A. 7 hours. B. 84 years. C. 21 years. D. 8 hours. E. 42 years.

E. 42 years

What is the prediction for the future of Triton? A. It will crash into Nereid when the smaller moon comes too close. B. It will develop active volcanoes as Neptune's tidal stresses become greater. C. Its retrograde orbit will throw it back out into the Kuiper Belt again, with Pluto. D. Its orbit, while retrograde, is very stable and will not change. E. It will provide the raw material for a future Neptunian ring.

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

In 1989, Neptune was found to have a huge storm named the: A. Great Red Spot. B. Galileo Regio. C. Hellas Basin. D. South Tropical Disturbance. E. Great Dark Spot.

E. The Great Dark Spot

The magnetic field tilts of which two bodies are the most unusual? A. Mars and Saturn B. Mercury and Earth C. Saturn and Venus D. Jupiter and Saturn E. Uranus and Neptune

E. Uranus and Neptune

The planet Neptune is: A. barely visible with the naked eye. B. only visible with a large, high-quality telescope. C. only visible with a space-based telescope. D. easily visible with the naked eye. E. visible with at least small telescopes or binoculars.

E. visible with at least small telescopes or binoculars.