THE ATMOSPHERE of JUPITER

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Jupiter’s stunning appearance is due to its atmosphere of swirling clouds and colorful bands, which alternately flow east and west. The atmosphere is mostly hydrogen and helium, but the visible clouds are ammonia. Underneath, there are water clouds. Even after over 200 years, the winds have largely remained unchanged, although the intensity of the colors and width of the bands have varied.

The famous Great Red Spot, as big as two Earths, is at least 300 years old. The reds, oranges and other colors arise from chemical reactions, which are probably driven by processes like lightning. 

JUPITER’S ATMOSPHERE IS MOSTLY HYDROGEN AND HELIUM, WHICH ARE THE LIGHTEST AND MOST ABUNDANT GASES IN THE UNIVERSE.

The weather on Earth is mainly driven by heat from the sun. But the sunlight on Jupiter is 25 times weaker than that on Earth, yet its winds are three to four times stronger. In some places, the wind whips through the atmosphere at 575 kilometers (360 miles) per hour.

One of Juno’s most important tasks is to use its Microwave Radiometer to measure how much of Jupiter’s atmosphere is composed of water. Since water is made from oxygen and hydrogen, measuring Jupiter’s water content is a way to determine how much oxygen there is in the planet – a crucial piece of information needed to understand how Jupiter formed.

Jupiter contains a fair amount of heavy elements, and no one is sure how they got there. One idea is that these elements hitched a ride on chunks of ice that crashed into Jupiter. Knowing how much water there is on Jupiter will help us determine whether this picture is accurate and understand what the solar system was like while the planet was forming.

Juno will also learn whether Jupiter’s atmospheric features – like its famous bands and Great Red Spot – are connected to the structure and motions of gas deep in its interior, or if they’re shallow patterns on the outermost layer of the atmosphere, like drops of oil on a pool of water. To find out, Juno will use its Microwave Radiometer and infrared camera to measure interior temperature, structure and motion.

Explore

Interact with the hotspots below to learn more.
  • HOT SPOTS

    These dark regions in Jupiter’s atmosphere are mostly cloud-free, providing a window into Jupiter’s hot interior.


  • CLOUDS AND LIGHTNING

    With clouds made out of chemicals we use for cleaning fluid, and with lightning three times brighter than on Earth, the weather on Jupiter is wild.


  • WHAT’S IT MADE OF?

    For the most part, Jupiter’s composition is similar to that of the Sun – but there are some puzzling differences.


  • HOW DEEP IS THE ATMOSPHERE?

    Jupiter’s atmosphere is actually quite thin.


  • THE GREAT RED SPOT

    Jupiter’s most famous feature is a red oval several times wider than our entire planet.


  • IS THERE LIFE ON JUPITER?

    As far as we know, Jupiter is not a place suitable for life.


  • THE STRIPE THAT DISAPPEARED

    One of Jupiter’s prominent dark belts vanished. What happened?


  • THE WEATHER ON JUPITER

    What will Juno tell us about the weather on Jupiter?