Discover the cosmos!
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Explanation:
Why are parts of this asteroid’s surface so smooth?
The answer seems likely to do with the dynamics of an
asteroid that is a loose
pile of rubble rather than a solid rock.
The unusual asteroid
Itokawa was visited by the
Japanese spacecraft
Hayabusa in 2005 which imaged and
documented its unusual structure and mysterious
lack of craters.
Analyses of the border regions between smooth and rugged sections indicate that jostling of the asteroid might be creating segregation between large and small rocks near the surface, like the
Brazil nut effect.
The robotic Hayabusa actually
touched down
on one of the smooth patches, dubbed the
MUSES Sea, and collected
soil samples.
These samples were
returned to Earth and are not only
giving clues to the ancient history of
this unusual asteroid,
but also about the early years of our entire
Solar System.
Computer simulations show that 500-meter asteroid Itokawa may
impact the Earth within the next few million years.
