Kepler's Hunt for Another Planet Earth in Space

The United Nations has named 2009 thethe last two decades. The Kepler probe will be
International Year of Astronomy. The year waslaunched into an Earth-trailing orbit around the Sun
chosen by the United Nations because it marksby a Delta booster rocket. Its telescope is being
the four hundred year anniversary of Italiandesigned to precisely measure the light from stars
astronomer Galileo Galilei's first observations usingin a one hundred square degree part of the sky in
a telescope.the constellation of Cygnus to discover both the
The International Year of Astronomy will featuresize and orbit of undetected new worlds.
a number of interesting international spaceIt is estimated that the target area of the
projects and events. The European Spacetelescope's observation is home to more than one
Agency has plans to launch a roving laboratory tohundred thousand stars. The spacecraft's
Mars. Richard Branson's Virgin Galactic servicephotometer will be able to detect small decreases
plans to offer commercial sub-orbital space flightsin stellar brightness when a planet "transits" its
that should commence in 2009. Russia should bestar. Three transits with a consistent period,
able to launch its laboratory module for thebrightness change, and duration will provide NASA
International Space Station.scientists with evidence of the detection of an
However, the most exciting mission in theextra-solar planet. Kepler is scheduled to focus
International Year of Astronomy may well be theexclusively on the constellation Cygnus target
NASA Discovery Mission called Kepler. NASAarea for four years with a possible two-year
intends to send a probe into space capable ofextension.
finding small planets like Earth that have theThe Kepler probe is important not only for what it
possibility of supporting life. The Kepler telescopemay find, but also for what it may not find. For
is looking for planets in the "habitable zone" ofexample, if Kepler can't locate smaller planets like
their star or at distances that would allow oceansEarth, it may be that planets with "habitable
to exist.zones" are rare in space. Earth may indeed be
To date, more than two hundred extra solartruly unique. However, if planets with a size and
planets have been found, but none of theselocation similar to Earth are discovered, there
discoveries is a planet similar to the Earth. Thewould be Earth-like planets to target for
fact is that it is very difficult to detect a planet assubsequent NASA space missions.
small as Earth in orbit around a distant star. A tinyThe launch of Kepler is now only one year away
planet like Earth only reflects the light from theand will mark an effort to discover our place in
star and does not shine on its own. In addition,the universe. If you believe unidentified flying
this faint planet light appears to be so close to theobjects (UFO) exist or simply that life indeed
much brighter star that they are almostmust exist elsewhere, NASA’s Kepler mission
impossible to tell apart. The 2009 Kepler Spaceshould be a highlight in the International Year of
Laboratory is being designed to go beyond theAstronomy.
Hubble Telescope and traditional Earth-boundOf course, the ultimate question in space
telescopes to locate rocky Earth-sized planets.exploration is the question, are we alone in the
Kepler will be a space-based probe with a cost ofuniverse? In 2009, the Kepler Space Laboratory
over five hundred fifty million dollars. It will usebegins the journey to find out the answer, as it
state of the art technology (opticalfulfills its mission to hunt for life supporting planets
interferometry) that has been refined only withinlike Earth in space.