The Solar System

H

H

H H

L

L

100

• 100


• 200

200

• 300 – 200 – 100 0 100 212

0

Altitude (km)

Temperature (°F)

Temperature (K)

100 200 300 400

Clear hydrogen

atmosphere

Ammonia

Ammonia hydrosulfide

Water

To liquid interior

L

L

L

L

H

H

H

North Equator

Altitude

Belt Zone

NASA/ESA/A. Simon-Miller NASA/GSFC/ I. de Pater/UC Berkeley

Zones are brighter than belts

because rising gas forms

clouds high in the atmosphere,

where sunlight is strong.

Great Red Spot

Red Jr.

Enhanced visible + infrared

2

3

The visible clouds on Jupiter are composed of
ammonia crystals, but models predict that deeper
layers of clouds contain ammonia hydrosulfide crystals,
and deeper still lies a cloud layer of water droplets.
These compounds are normally white, so planetary
scientists think the colors arise from small amounts of
other molecules formed in reactions powered by
lightning or sunlight.

If you could put thermometers in Jupiter’s atmosphere at
different levels, you would discover that the temperature
rises below the uppermost clouds.

Far below the clouds, the temperature and pressure
climb so high the gaseous atmosphere merges
gradually with the liquid hydrogen interior and there is
no surface.

4 Three circulating storms visible

as white ovals since the 1930s

merged in 1998 to form a single white

oval. In 2006, the storm intensified and

turned red like the Great Red Spot. The

reason for the red color is unknown, but it

may show that the storm is bringing material

up from lower in the atmosphere.

Storms in Jupiter’s atmosphere may be stable

for decades or centuries, but astronomers had

never before witnessed the appearance of a new

red spot. It may eventually vanish or develop further.

Even the Great Red Spot may someday vanish.

On both

Earth and

Jupiter, winds

circulate

clockwise around

the high-pressure

areas in the northern

hemisphere and

counterclockwise south of the

equator.

The

poles and

equator on

Jupiter are about the

same temperature,

perhaps because of

heat rising from the

interior. Consequently,

there are no

wave-shaped winds, and

the planet’s rapid rotation

stretches the high- and

low-pressure areas into belts and

zones that circle the planet.

On

Earth, the

temperature

difference

between

the poles and equator drives a

wave-shaped high-speed wind

that organizes the high- and

low-pressure areas into

cyclonic circulations familiar

from weather maps.