Weather on Jupiter
Written by Fraser Cain
Although Jupiter is mostly made of hydrogen and helium, it's uppermost cloud tops are composed of ammonia crystals. These clouds are broken up into bands at different latitudes of the planet, which whirl around the planet in opposite directions.
They do change slightly over time, but these bands have remained so remarkably stable that astronomers have been able to give them names and designations. There are six major belts (the dark stripes), with names like the North and South Equatorial belts. And then there are seven zones (the light stripes), with names like the North and Tropical zone.
NASA's Galileo spacecraft recorded wind speeds of up to 220 m/s (800 km/h), and getting faster as you do deeper down within the planet.
The powerful weather patterns on Jupiter come from its dense atmosphere, and rapid rotation. It's the rotation that creates the Coriolis Effect, which separates the planet into the various circulation cells.
There are many storms that whirl inside the bands, but the most famous of these is the Great Red Spot; a feature on the border of the South Equatorial belt and has been seen on the planet for at least 300 years. A second storm, Oval BA, was first seen in 2000 after three small white storms collided together. It has been growing in size and recently turned red as well. Astronomers have taken to calling it Red Jr.
Here's an article from Universe Today about how the Hubble Space Telescope has watched Jupiter change over time, and how gigantic storms on Jupiter can grow in a single day.
Here's an article from NASA about storms converging on Jupiter, and an article about how Jupiter's heat creates the storms.
We've also recorded an entire show just on Jupiter for Astronomy Cast. Listen to it here, Episode 56: Jupiter, and Episode 57: Jupiter's Moons.
Filed under: Astronomy
