Following the path of one of Jupiter's jet streams, a line of V-shaped chevrons travels west to east just above Jupiter's Great Red Spot. Most of the planet is unfolded here in a single, flat map made on December 11 and 12, 2000, when NASA's Cassini spacecraft flew past Jupiter. At the left, the chevrons run into another storm called the South Equatorial Disturbance (SED). Credit: NASA/JPL/Space Science Institute
New movies of Jupiter are the first to catch an invisible wave shaking up one of the giant planet’s jet streams, an interaction that also takes place in Earth’s atmosphere and influences the weather.
The movies, made from images taken by NASA’s Cassini spacecraft when it flew by Jupiter in 2000, are part of an in-depth study conducted by a team of scientists and amateur astronomers led by Amy Simon-Miller at NASA’s Goddard Space Flight Center in Greenbelt, Md., and published in the April 2012 issue of Icarus.
“This is the first time anyone has actually seen direct wave motion in one of Jupiter’s jet streams,” says Simon-Miller, the paper’s lead author. “And by comparing this type of interaction in Earth’s atmosphere to what happens on a planet as radically different as Jupiter, we can learn a lot about both planets.”
Like Earth, Jupiter has several fast-moving jet streams that circle the globe. Earth’s strongest and best known jet streams are those near the north and south poles; as these winds blow west to east, they take the scenic route, wandering north and south. What sets these jet streams on their meandering paths — and sometimes makes them blast Florida and other warm places with frigid air — are their encounters with slow-moving waves in Earth’s atmosphere, called Rossby waves.
The photo at left of Jupiter is from the NASA website: 