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.

September 2, 1998
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Saturn from Earth
Credit & Copyright: Nordic Optical Telescope

Explanation: Saturn is the second largest planet in our Solar System. Saturn has been easily visible in the sky since history has been recorded. Galileo used one of the first telescopes in 1610 to discover Saturn's rings, which he first thought were moons. Maxwell showed in 1856 that Saturn's rings couldn't be a single solid, since Saturn's own gravity would break it up. Were Saturn's rings assembled into a single body, it would measure less than 100 kilometers across. The origin of Saturn's rings, and of unusual radial patterns that appear on them called spokes, are still unknown. The above representative-color picture was taken from Earth in infrared light. A robot spacecraft Cassini launched in 1997 will reach Saturn in 2004.

Tomorrow's picture: SGR: Magnetar

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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.