[meteorite-list] Hayabusa Spacecraft Rounds Earth and Heads for Near-Earth Asteroid

[Ron Baalke]

Hayabusa Spacecraft Rounds Earth and Heads for Near-Earth Asteroid
Don Yeomans and Paul Chodas
May 19, 2004

At 6:23 am (Greenwich time) on May 19, the Japanese Hayabusa 
spacecraft successfully made a close Earth approach 
(altitude = 3725 km), thereby gaining the velocity it needs 
to reach the near-Earth asteroid Itokawa, named for the 
father of Japanese rocketry.

During the Earth swingby, the spacecraft took images of the 
Earth and moon to test and calibrate the on board camera 
called AMICA (Asteroid Multi-band Imaging Camera).  These Earth 
and lunar images can be viewed at:
 
http://www.isas.ac.jp/e/snews/2004/0519.shtml
 
Upon its arrival at the asteroid in the summer of 2005, the 
Hayabusa spacecraft will hover near the asteroid's surface for 
about four months.  Its instruments will study the surface in 
detail, determine the asteroid's mass and bulk density and 
determine which minerals are present.  A small coffee-can-sized 
surface hopper, called MINERVA, will leap about the asteroid 
taking surface temperature measurements and high-resolution 
images with each of its three miniature cameras.  

The spacecraft will collect up to three surface samples as its 
sample horn captures small pieces of the asteroid ejected when 
tantalum pellets are fired into its surface at 300 meters per 
second.  With these surface samples tucked safely into the 
spacecraft's sample capsule, the spacecraft will return to 
Earth, arriving on June 10, 2007, and the sample capsule will 
parachute to the ground in Australia.  The samples will be 
analyzed in various laboratories to study their detailed 
chemical composition and determine which meteorite examples in 
Earth-based collections provide the best match for Itokawa's 
particular composition.

Hayabusa, which is Japanese for "falcon", will act much like 
its namesake, descending to the asteroid's surface, capturing 
its prey and returning it to Earth.  While the scientific 
knowledge of near-Earth asteroids will be significantly 
advanced by the Hayabusa mission, the primary goals are to 
test four advanced technology systems:  the electric propulsion 
(ion drive) engines; an autonomous navigation system; the 
sample collection system; and the sample capsule that re-enters 
the Earth's atmosphere.    

Additional information:

Hayabusa Project (JAXA main site)
http://www.jaxa.jp/missions/projects/sat/exploration/muses_c/index_e.html

SPACE NEWS (ISAS) -- Hayabusa acquired images of the earth and the moon.
http://www.isas.jaxa.jp/e/snews/2004/0519.shtml

Planetary Society:
http://planetary.org/news/2004/hayabusa_earth-swingby_preview.html