Explanation:
How common are planetary systems like our own?
Perhaps quite
common, as the first system of planets like our own Solar System has been
discovered
using a newly adapted technique that, so far, has probed only six
planetary systems.
The technique, called
gravitational microlensing,
looks for telling brightness changes in measured starlight when a foreground
star with planets
chances almost directly in front of a more distant star.
The distant star's light is slightly
deflected in predictable ways by the
gravity of the closer system.
Recently a detailed analysis of
microlensing system
OGLE-2006-BLG-109 has related
brightness variations to two planets that are similar to
Jupiter and
Saturn of our own Solar System.
This discovery carries the tantalizing implication that interior planets, possibly including
Earth-like planets,
might also be common.
Pictured above is an artistic conception of how the BLG-109 planetary system might look.
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