[meteorite-list] Hayabusa Touched Asteroid Itokawa After All

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed Nov 23 17:04:25 2005
Message-ID: <200511232202.jANM2vc20388_at_zagami.jpl.nasa.gov>

http://www.newscientistspace.com/article/dn8362-hayabusa-touched-asteroid-itokawa-after-all.html

Hayabusa touched asteroid Itokawa after all
Will Knight and Maggie McKee
New Scientist
23 November 2005

The Japanese space agency has announced that its Hayabusa spacecraft
successfully touched down on asteroid Itokawa during a rendezvous on
Sunday, although it failed to collect samples from its surface.

Hayabusa suffered a communications glitch while approaching Itokawa and,
by the time the link was re-established with Earth several hours later,
had drifted away from its target.

The Japan Aerospace Exploration Agency (JAXA) had to wait until the
spacecraft's high gain antenna was pointed back towards Earth before it
could say for certain whether Hayabusa had landed as hoped. This was so
that the spacecraft could transmit detailed data from the sensors and
navigation equipment.

This data has now shown that Hayabusa managed to drop onto the
asteroid's surface for about 30 minutes, even though it was only meant
to make contact with the asteroid for about 1 second.

Inadvertent sample

The probe apparently failed to fire a pellet into the rocky body's
surface so that it could collect the resulting dust and debris. But the
spacecraft's navigation data reveals that it collided with the
asteroid's surface several times. One mission team member says this
means it might have disturbed enough surface debris for some to be
collected in its sample capture instrument.

JAXA will decide on Thursday whether to make a second attempt to land
and collect a surface sample. The probe is not thought to have suffered
any major damage, but some of its sensors need to be checked, the agency
says.

If the mission succeeds it would be the first time that material from an
asteroid has been brought back to Earth. The sample could help
scientists learn more about the formation of the solar system -
asteroids are thought to be made of primordial planetary matter.

Series of hiccups

Prior to Sunday's rendezvous, Hayabusa released a small metal
ball-shaped "target marker" onto the asteroid to mark the point where it
would touch down. The marker contains an aluminium plate bearing the
names of 880,000 people from 149 countries around the world, among them
US filmmaker Steven Spielberg and British science fiction author Arthur
C Clarke.

The mission has already suffered a series of hiccups. On 12 November,
Hayabusa lost contact with a small robotic rover - called Minerva - that
was designed to hop around the surface of the asteroid capturing images
and taking temperature readings. Mission controllers believe Minerva
missed the asteroid entirely and drifted off into space.

A practice descent was also aborted on 4 November when the
probe sent an "anomalous signal" back to mission control.

The spacecraft is scheduled to return to Earth mid-2007 but must leave
the asteroid by early December 2005 in order to make it safely. If it
fails to collect a sample from the asteroid, mission controllers are not
sure they will call the craft home.
Received on Wed 23 Nov 2005 05:02:56 PM PST