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.

October 13, 1997

Ice Clouds over Mars
Credit: IMP Team, JPL, NASA

Explanation: Mars has clouds too. The above true color image taken in August by Mars Pathfinder shows clouds of ice high in the Martian atmosphere. Unlike Earth's atmosphere which is composed predominantly of nitrogen and oxygen, Mars' atmosphere is composed mostly of carbon dioxide. Nevertheless, a trace amount of water does freeze into visible clouds at night, which become particularly apparent during the day by reflection of sunlight. Contact was lost with Mars Pathfinder last Sunday but re-established later in the week.

Tomorrow's picture: Venus On The Horizon

< Archive | Index | Search | Calendar | Glossary | Education | About APOD >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.