Explanation:
What's that unusual looking spot on asteroid Itokawa? It's the shadow of the
robot spacecraft Hayabusa
that took the image.
Japan's
Hayabusa mission
arrived at the
asteroid
in early September and has been imaging and maneuvering around the
floating space mountain ever since.
The above picture was taken earlier this month.
Asteroid Itokawa
spans about 300 meters.
One scientific goal of the
Hayabusa mission
is to determine out how much ice, rock and trace elements reside on the
asteroid's surface, which should give indications about how asteroids and
planets formed in the early Solar System.
A can-sized robot MINERVA that was scheduled to hop
around the asteroid's surface has
not, so far, functioned as hoped.
Later this month,
Hayabusa is scheduled to descend to asteroid Itokawa and collect surface samples in a
return capsule.
In December, Hayabusa will fire its rockets toward Earth and drop the
return capsule down to Earth's
Australian outback in 2007 June.