EMBARGOED for
Mars' moon Phobos is unlike Earth's Moon in most ways. For starters, it zips
around Mars three times a day. Phobos practically hugs its host -- orbiting
just 3,728 miles (6,000 kilometers) away. Our Moon averages 238,900 miles (384,402
kilometers) of distance.
From Mars, Phobos would appear about one-third as big as Earth's Moon. If you
stood on Phobos, Mars would fill almost the entire sky, astronomers say.
Phobos is shaped like a potato, measuring roughly 17x14x11 miles (27x22x18
kilometers). It's a mere 0.006 times the size of Earth's Moon.
This new picture, released June 1, was taken by NASA's Mars Global Surveyor.
One thing both moons have in common: they've been
rocked by impacts. See the pits and groves that are lined up on Phobos? Astronomers
figure those were created when another space rock hit Phobos on the other side,
leaving a crater called Stickney that can't be seen in this picture. Once there's
an impact, stuff flies around and all sorts of other collisions occur. You can
see Stickney and learn more about Phobos (and Deimos, Mars' other moon) here.
-- Robert
Roy Britt
Credit: NASA/JPL/Malin Space Science Systems
| 
