Changing weather report on Jupiter


  • Michael Carlowicz


With two months to further refine their data sets according to corrections in instrument calibrations, principal investigators for the Galileo probe of Jupiter are revising their report on the chemistry and weather of the gas giant.

The composition of Jupiter's upper atmosphere is more Sun-like than scientists suggested at a January presentation of probe results (Eos, January 30, 1996). A more comprehensive analysis of data from the helium abundance detector—as well as correlation with the neutral mass spectrometer—reveals that the percentage of helium in the Jovian atmosphere is roughly 24%. That figure is significantly higher than the 13.7% announced in January and is quite close to the composition of the Sun.