Over the
last 10 years
astronomers have
discovered more than
800 rocky exoplanets,
that is, planets
roughly the size of
Earth. The resulting
statistics indicate
every star hosts ~1 or
more of these worlds
-- so, our galaxy is
filled with them. Just
as astonishing, we
know little else about
these planets. The
data we currently have
only constrain the
planetary radius, and
occasionally the bulk
mass, of most rocky
exoplanets. For
comparison, that is
like talking about the
Solar System if all we
knew about Mercury
versus Venus versus
Earth is how big they
were. In this talk I
will review what is
currently known (and
not known) about rocky
exoplanets. There are
still many fundamental
questions about these
worlds, perhaps the
most important one
being whether most
rocky exoplanets even
have an atmosphere.
Luckily, thanks to a
number of recent
telescope
developments, we
should be able to
settle the question in
the next 1-2 years.
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