Jupiter is the largest planet in our solar system. It is largely composed of gases (primarily hydrogen and helium, with small amounts of methane, water, ammonia, and other compounds) and contains more than twice the mass of all the other planets in the solar system combined. Its well-known bands of colors are clouds that reveal the weather in its outer atmosphere. Adjacent bands of wind blow in opposite directions, and they vary in color because of differences in chemical composition and temperature. Vortices—rotating structures similar to whirlpools or hurricanes—develop in the turbulent boundary regions between bands. Depending on the direction of rotation, the vortices may be called cyclones or anticyclones.

The Great Red Spot is Jupiter's largest anticyclone—it is a giant, persistent storm that is large enough to be visible through ground-based telescopes and has captured the interest of people for centuries. Storms on Jupiter can last much longer than they do on Earth because they have a continuous source of energy. On Earth, hurricanes form when water evaporates from warm oceans and rises into the air as water vapor. As the vapor rises and cools, it condenses to form clouds and precipitation, a process that releases heat which further drives the evaporation process. Storms feed off of this evaporation and condensation loop but they lose strength when their source of energy and the evaporation lessens, such as when they hit land. On Jupiter, storms can last a very long time because there is no land and weather is driven largely by the consistent internal heat of the planet. This is different from Earth's weather, which is fueled by solar energy heating the Earth.

However, Jupiter's weather is always changing. New storms form and storms may dissipate or combine with other vortices. As seen in the video, recent changes in Jupiter's atmospheric activity may be indicative of a changing climate. Vortices are a way to transport heat to keep the temperature of Jupiter relatively uniform. The merger of storms and the emergence of new storms may be related to a major global climate change in which the planet's poles are cooling while the mid-latitudes are warming.

Both ground-based and space-based observations (such as from the Galileo and Cassini spacecraft) provide key data. While spacecraft provide detailed observations, the observations are limited by the timeline and longevity of the mission. Scientists rely on observations from telescopes on Earth for more continuous data. Observations at infrared wavelengths (infrared radiation is a range in the electromagnetic spectrum beyond the red wavelengths of visible light) are especially useful in studying Jupiter's weather because they reveal temperature differences and details of cloud structures that are not seen in other wavelengths.

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