Scientists have for the first time observed waves in one of Jupiter's jet streams.
The researchers observed the waves on videos Cassini made from Jupiter in 2000. The films are being thoroughly studied at the moment. And apparently there is still plenty to discover.
The situation on earth. Image: NASA / GSFC.
There are various fast-moving jet streams around Jupiter. On earth we also have those jet streams, the strongest and best known can be found at the poles. These jet streams move in principle from west to east. But when they encounter slower waves in the atmosphere (called Rossby waves), they can also move north or south (see the picture on the right). The jet streams and Rossby waves together exert a considerable influence on the weather.
The jet streams on Jupiter did not initially seem that capricious. It is already known that Jupiter also has Rossby waves. Only it had never been observed that these played with the southern jet streams. Until now. For the first time, researchers are witnessing that the jet streams on Jupiter sometimes stray.
Researchers are happy with the information they have collected. "Understanding the similarities and differences between earth and Jupiter helps us to figure out what an atmosphere is and how it can behave," says Gianluigi Adamoli, among others. Researcher Amy Simon-Miller adds: "And by comparing this interaction (between Rossby waves and jet streams) in the Earth's atmosphere with what happens on a totally different planet such as Jupiter, we can learn a lot about both planets."