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.

March 12, 1998

Moon Shadow
Credit: GOES Project, GSFC, NASA

Explanation: When the Moon's shadow reached out and touched the Earth last month, the result was a Solar Eclipse. Such an eclipse is total only for observers located along a narrow path corresponding to the ground track of the shadow's dark central portion or "umbra". For this eclipse, racing along at nearly 1,200 miles per hour, the Moon's umbra obligingly crossed over land along pleasant tropical locales in South America and the Caribbean islands. Totality lasted for about 3 minutes or less at a given location. Sizable fractions of North and South America fell within the lighter but much wider outer shadow region, the "penumbra", and witnessed a partial eclipse. This movie gif follows the Moon's shadow from Central and South America eastward across the Atlantic - as seen from the vantage point of an orbiting Geostationary Operational Environmental Satellite (GOES), 22,000 miles above Earth. The three frame animation spans about 2 hours. GOES satellite images are a corner stone of U.S. weather monitoring and forecast operations.

Tomorrow's picture: Asteroids

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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.