Astronomy Ch. 11 – Jupiter

Jupiter is noticeably oblate because:

it rotates rapidly.

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

It is twice as massive as all other planets combined.

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

Its density is less than any terrestrial.

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

by radio observations of Jupiter’s rapidly spinning magnetosphere

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.

What is interesting about Jupiter’s rotation period?

It is the fastest in the solar system.

Essentially, the Great Red Spot is

a large cyclonic storm (hurricane).

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

belts

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

Great Red Spot.

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

differential rotation and the underlying zonal flow

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

Galileo.

The white zones of Jupiter are probably made of:

ammonia ice.

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

large mass.

The only spacecraft to go into orbit around Jupiter was:

Galileo.

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.

The belts of Jupiter are best described as follows:

regions of downward moving material and low pressure.

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

Hydrogen and Helium

Which of these spacecraft did not go to Jupiter?

Mariner 9

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

create light and dark bands.

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 is the source of Jupiter’s nonthermal radio radiation?

metallic hydrogen swirling in the planet’s interior

What is the source of Jupiter’s excess energy?

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

What would Jupiter have needed to have become a star?

more mass

What is thought to lie at the center of Jupiter?

a massive core of rocky materials with some iron mixed in

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 true of Jupiter’s magnetosphere?

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

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

liquid metallic hydrogen swirling in the rapidly spinning mantle

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

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

How large is Jupiter’s magnetosphere?

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

What do our magnetic field and Jupiter’s share?

auroral displays in the polar regions

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

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

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

tidal stresses from both Jupiter and Europa

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

Io

What is the origin of the jovian moons?

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

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

Europa

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

Callisto

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

Galileo

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

Ganymede.

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

Ganymede

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

sulfur and its compounds

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.

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

Europa, Ganymede, and Callisto

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

Ganymede, Callisto, Io, Europa.

Which statement about Jupiter’s moons is FALSE?

All have counterclockwise revolution around the giant planet.

Which of the four Galilean moons is not differentiated?

Callisto

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

Ganymede and Callisto

Where is Jupiter’s ring located?

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

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

a thin ring of dust around the equator.

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

Jupiter has cloud bands in its upper atmosphere.

Which statement about Jupiter’s rings is false?

They are made of ice, like Saturn’s.

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.

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.

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 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.

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.