[meteorite-list] Asteroid Vesta A Speck in Space, But It's Visible

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed Dec 28 13:14:28 2005
Message-ID: <200512281812.jBSICop28413_at_zagami.jpl.nasa.gov>

http://www.signonsandiego.com/news/science/20051228-9999-1c28star.html

Asteroid Vesta a speck in space, but it's visible
San Diego Unon-Tribune
December 28, 2005

In the void between Mars and Jupiter lie millions - perhaps billions -
of rocks known as asteroids. Most range in size from tiny pebbles to
chunks the size of mountains. The largest of these, known as Ceres, is a
mere 600 miles across, yet contains nearly half the mass of all
asteroids combined. It was also the first such body to be found - on New
Year's Day, 1801.

The fourth to be discovered was Vesta. With a diameter of 326 miles -
about the size of Arizona - Vesta appears to even the largest telescopes
as a speck of light the size of a dime seen from five miles away.

Astronomers have learned that Vesta reflects 25 percent of all sunlight
falling onto its surface, and this accounts for its brightness. (The
moon, by comparison, reflects only 12 percent.) Vesta holds the
distinction of being the brightest of all asteroids, occasionally
appearing to binoculars - even the unaided eye - from a dark rural site.
Right now is one of those times - a time known as Vesta's "opposition."

Opposition, as regular readers might recall, is a time when a celestial
object appears opposite in the sky from the sun. It's during this time
that a body lies closest to Earth and reaches its brightest. Vesta
officially reaches this point Jan. 5, when it lies "only" 143,781,413
miles away.

Dedicated stargazers may wish to brave the cold winter evenings to scan
the eastern sky for Vesta. After dark, find Gemini, the twins, marked by
the bright stars Castor and Pollux. Below is a more-faint star known as
Kappa Geminorum. Aim binoculars toward this star, sliding them downward
so the star is near the top of your field of view. You should see a star
pattern like that in the accompanying illustration, with Vesta near the
center.

To be sure it's Vesta, make a sketch of the stars you see and return
night after night. You should soon notice that one of these "stars" is
moving through this stellar pattern.

This, of course, is no star. It's Vesta.
Received on Wed 28 Dec 2005 01:12:49 PM PST