The two planets are more alike than researchers first suspected

Mar 14, 2012 07:43 GMT  ·  By
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
   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

A series of short video clips depicting the cloud cover above Jupiter indicates that an invisible wave is influencing the gas giant's atmosphere in a pattern similar to what planetary scientists have already observed here on Earth.

The recently-found wave is influencing one of Jupiter's largest jet streams, investigators say. Most of the short clips were put together from data collected during a slow Cassini flyby in 2000. The probe was on its way to Saturn at that time, which it reached in July 2004.

On Earth, invisible atmospheric waves called Rossby waves are known to influence weather patterns. What researchers want to learn is what effects the passing of these waves has on Jupiter's jet streams.

The question is a very pertinent one, considering the huge array of differences between the two worlds. For starters, there is no land on the gas giant, and seasons are also absent. Yet, researchers are seeing cyclones and anticyclones on both planets.

These similarities are precisely the reason why studying Jupiter's atmosphere is so important. By understanding how various phenomena occur above multiple planets, scientists may be able to figure out what is normal for an atmosphere to do, and what is not.

Ultimately, this could lead to a better understanding of our own planet, and the extent to which Rossby waves influence weather and climate here. Experts publish details of their new study in Jupiter's atmosphere in the April 2012 issue of the scientific journal Icarus.

“This is the first time anyone has actually seen direct wave motion in one of Jupiter's jet streams. 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,” Amy Simon-Miller explains.

The scientist, who was the lead author on the new paper, is based at the NASA Goddard Space Flight Center (GSFC), in Greenbelt, Maryland.

“A planet's atmosphere is a lot like the string of an instrument,” explains Michael D. Allison, a coauthor of the new research paper, and a researcher at the NASA Goddard Institute for Space Studies (GISS), in New York.

“If you pluck the string, it can resonate at different frequencies, which we hear as different notes. In the same way, an atmosphere can resonate with different modes, which is why we find different kinds of waves,” he adds.

Thus far, studies of Earth's atmosphere have largely been conducted for their own sake. In other words, very few investigations have focused on analyzing the atmosphere by comparison to the gaseous layers around other planets.