[meteorite-list] Ceres, The Biggest Asteroid, Will Be At Its Most Visible Soon

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri Jul 28 13:32:15 2006
Message-ID: <200607281729.KAA20417_at_zagami.jpl.nasa.gov>

http://www.mlive.com/features/aanews/index.ssf?/base/features-1/1154009429278160.xml&coll=2

Ceres, the biggest asteroid, will be at its most visible soon
BY ANNE RUETER
Ann Arbor News
July 27, 2006

Asteroids are great examples of the truism that intriguing gifts come in
small packages. "Minor planets'' is one term astronomers use for these
rocky objects that orbit within the inner solar system, mostly between
Mars and Jupiter.

Very minor: The biggest, Ceres, is only 595 miles across. Ceres makes
its best appearance in the next few weeks. On Aug. 12, Ceres will be as
visible as it gets when it reaches opposition. Even then, it will be
tricky to spot it with binoculars or a small telescope. Your luck will
be better if you attend a star party where bigger telescopes may be
trained on Ceres. The asteroid is traveling through the constellation
Piscis Austrinus (the Southern Fish), which is low in the southern sky.

Such small space objects can still kick up quite a bit of fuss. The idea
that a wandering asteroid could smack into Earth has spawned scary movie
plots and serious scientific efforts to track asteroids that come
relatively close - there are about 783 labeled "potentially hazardous
asteroids'' - and devise ways to steer them off course.

To Dan Scheeres, asteroids are also fascinating relics from the age when
planets formed in our solar system about 4.6 billion years ago. Scheeres
is a University of Michigan aerospace engineering professor skilled at
ways to maneuver around asteroids. He recently took part in the Japanese
space probe Hayabusa's mission to the asteroid Itokawa. The probe
orbited Itokawa last fall for three months and went down to the surface
twice to sample what the asteroid made of.

Close-up pictures of Itokawa reveal "it's really just a big rubble
pile,'' says Scheeres. "It's a really neat looking asteroid.''

On its small surface - only a half-kilometer long on its longest axis -
Itokawa has amazingly varied terrain, from building-sized boulders to
small bits of gravel. "It is really a little world unto itself,''
Scheeres says, one where if you were to visit, you would have to tread
very slowly and carefully. "If you sneeze, you might go into orbit.''

The Itokawa images suggest it's made of material that glommed together
after an earlier asteroid got shattered in a collision. Knowing that
asteroids are not necessarily solid rocks should help scientists figure
out how to nudge asteroids away if they appear headed toward a collision
with us.

For more information about the Hayabusa probe, including images noting
Itokawa's resemblance to a sea otter, visit
www.isas.ac.jp/e/enterp/missions/hayabusa/today.shtml.

For more on asteroids that come close to Earth, visit NASA's site on
near-Earth objects, neo.jpl.nasa.gov/neo.
Received on Fri 28 Jul 2006 01:29:34 PM PDT