Astronomy Ch. 13 - Uranus And Neptune

Uranus

above their equators.

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

has no internal energy source

that its atmosphere rotates more slowly than its interior

Miranda

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

Great Dark Spot

their atmospheres contain methane, which absorbs red light

Ammonia

Uranus

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

Hydrogen

Uranus and Neptune

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

Methane.

methane gas in their atmospheres absorbs red light well.

Uranus

Adams, Leverrier, and Galle

The Uranian rotation axis produces some extreme seasonal effects.

Uranus.

Great Dark Spot.

above their equators.

small with features similar to Jupiter.

less than 250 years ago.

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.

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

8 hours.

spacecraft exploration.

rotation rates.

Voyager 2

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.

imply the nearby presence of a massive body.

photometric observations of the occultation of a star made from Earth

Neptune

barely visible with the naked eye.

Uranus

Uranus

the father of Saturn.

only visible with a small telescope or binoculars.

a few degrees from where it was predicted to be.

Uranus

42 years

Methane

liquid nitrogen with carbon grit

Neptune's Triton

observations of the motions of their satellites.

Uranus

Methane

their atmospheres contain methane, which absorbs red light.

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.

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.

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

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

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.

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.

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.

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.

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.