Affordable Access

Publisher Website

New Observational Results Concerning Jupiter's Great Red Spot

Authors
Journal
Icarus
0019-1035
Publisher
Elsevier
Publication Date
Volume
158
Issue
1
Identifiers
DOI: 10.1006/icar.2002.6867

Abstract

Abstract The changing size and aspect ratio of the Great Red Spot from 1880 to 2000 are reviewed, indicating that the length of the system has decreased significantly over the last 100 years and continues to decrease at present at a rate of 0.19 degrees per year. Voyager IRIS maps of para hydrogen fraction and potential temperature over the system are presented, showing the internal structure and surrounding areas at pressures from 100 to 500 mbars. In these maps, the GRS appears as a cold temperature anomaly and a low para fraction anomaly. Vertical structure analyses and wind velocity measurements are presented from data acquired by the Galileo spacecraft in 1996 and 2000, respectively. The vertical structure data suggest a very thick, white, cloud deck with a top near 800±100 mbars and an extended, blue-absorbing, optically thick haze up to about 200 mbars with a thin stratospheric haze above it. The wind field shows a substantial increase in the maximum tangential velocity from 150 to 190 m s −1 over the Galileo time period. The vertical structure analyses from Galileo data and the wind and temperature fields from Voyager data all show evidence of a tilt to the Great Red Spot at the cloud deck from north to south and more subtly from east to west. The data support the hypothesis of the GRS as a tilted “pancake” with temporal variability to the tilt.

There are no comments yet on this publication. Be the first to share your thoughts.