Geotimes
Published by the American Geological Institute |
News
and Trends in the Geosciences
April 2000 |
The presence of storms, and even lightning, on Jupiter has been known since the Voyager missions of the late 1970s. However, the new data are more complete and reveal previously unobserved details of cloud structure and dynamics.
The researchers — from Caltech, Cornell, UCLA,
NASA’s Jet Propulsion Laboratory and Ames Research Center, ITRES Research,
and the Galileo team — deduced from Galileo’s images that storms
on Jupiter produce both water condensation and lightning. In comparing
this information to other parameters, such as lightning depth, the research
team concluded that convection of internal heat produces the storms.
Above: Galileo mapped
these images of two jovian storms.
Top: Superimposing images with different wavelengths and ability to absorb methane created the top color image. The different colors represent different depths (or pressures) sunlight can penetrate the atmosphere: blue (about 0.5 bar), green (3 bar) and red (deeper than 3 bar). Middle: Blue lightning strikes, photographed from nighttime images of the storm, are overlaid on a black-and-white image of the storm during the day. Bottom: Wind vectors overlaid on the bottom image show counterclockwise rotation just east of the storm at 265 degrees west longitude. This anticyclonic vorticity contrasts with a strong cyclonic shear at 269 degrees west longitude, slightly northwest of the storm. Image courtesy of NASA/JPL/Cornell |
Josh Chamot
Geotimes contributing
writer