APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Io's Sodium Cloud
Explanation: Explanation : Io has its own cloud. Jupiter 's most active moon is visible on the left of the above false-color photograph , with its left side illuminated by sunlight. But what is happening on Io 's right side? Here a plume of gas from the active volcano Prometheus also reflects sunlight. A second active volcano, Pele , is also visible: marked by the red spot just below Io 's center. Surrounding the moon is a yellow haze originating from gas ejected by Io's volcanos . Sodium atoms in the gas cloud are particulary efficient at reflecting yellow light . Several points of light are background stars.
| Date | April 28, 1997 |
|---|---|
| Credit |
Io's Sodium Cloud Credit: Galileo Project, JPL, NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |