Beyond the Realm of the Giants
Science writer and space
artist Mark Garlick tries to envision things we can't always see. This view
is of a pair of boulders orbiting each other in the outer solar system, beyond
the giant planets Uranus and Neptune.
They're called Kuiper Belt
Objects (KBOs). Astronomers don't know much about them, but they're thought
to be chunks of ice and rock that formed when the planets took shape, more than
4 billion years ago. The most powerful telescopes show them only as points of
reflected sunlight.
Larger KBOs should be round,
because gravity would make them so. An example might be the recently discovered
object named Sedna,
which resides beyond Pluto but whose origins are not precisely known.
"The two objects here are
small and therefore irregularly shaped," Garlick explained.
Even round objects in the
Kuiper Belt -- the source of some comets -- are likely somewhat ragged. Two
apparent examples include Saturn's moon Phoebe,
which is thought to be a captured KBO. And Comet Wild
2, recently photographed by the Stardust spacecraft, looks wildly different
from Phoebe but may have similar origins.
What's perhaps most amazing
about KBOs is that, like asteroids and just about everything else we know of
in the universe, they sometimes have orbiting companions. Garlick envisioned
this orbiting pair after their discovery
in 2001. Neptune
is in the background, eclipsing the Sun.
More of Garlick's artwork
can be viewed on his web site.
-- Robert
Roy Britt
Credit and Copyright:
Mark Garlick
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