zorg.ch
19:05 Uhr
Events
Forum
Games
Wetten
Rezepte
Tauschbörse
Books
Space
User
Übersicht
Astronomy Picture of the Day
The Missing Craters of Asteroid Itokawa
Bild Note: 0
(0 Votes)
⏴ previous
Bild Upload von 18.02.2016 21:43
next ⏵
zorg.ch
#81869
by
[z]Barbara Harris
@
22.11.2005 00:00
- nach oben -
The Missing Craters of Asteroid Itokawa
Explanation:
Where are the craters on asteroid Itokawa? No one knows.
The Japanese robot
probe Hayabusa
recently
approached
the
Earth-crossing asteroid
and is
returning pictures
showing a surface unlike any other
Solar System
body yet photographed -- a surface possibly devoid of
craters
.
One possibility for the lack of
common circular indentations
is that
asteroid Itokawa
is a
rubble pile
-- a bunch of rocks and ice chunks only loosely held together
by a small amount of gravity.
If so, craters might be filled in whenever the
asteroid
gets jiggled by a passing planet --
Earth in this case.
Alternatively, surface particles may become
electrically charged by the Sun
, levitate in the
microgravity
field,
and move to fill in craters.
Over the weekend,
Hayabusa lowered
itself to the surface of the
strange asteroid
in an
effort to study the unusual body and collect surface
samples that could be returned to Earth in 2007.
Credit & Copyright