An
international team of professional and amateur
astronomers, using simple off-the-shelf equipment to
trawl the skies for planets outside our solar system,
has hauled in its first "catch."
The astronomers discovered a Jupiter-sized planet
orbiting a Sun-like star 600 light-years from Earth in
the constellation Corona Borealis. The team, led by
Peter McCullough of the Space Telescope Science
Institute in Baltimore, Md., includes four amateur
astronomers from North America and Europe.
Using modest telescopes to search for extrasolar
planets allows for a productive collaboration between
professional and amateur astronomers that could
accelerate the planet quest.
"This discovery suggests that a fleet of modest
telescopes and the help of amateur astronomers can
search for transiting extrasolar planets many times
faster than we are now," McCullough said. The finding
has been accepted for publication in the Astrophysical
Journal.
McCullough deployed a
relatively inexpensive telescope made from commercial
equipment to scan the skies for extrasolar planets.
Called the XO telescope, it consists of two
200-millimeter telephoto camera lenses and looks like a
pair of binoculars. The telescope is on the summit of
the Haleakala volcano, in Hawaii.
"To replicate the XO prototype telescope would cost
$60,000," McCullough explained. "We have spent far more
than that on software, in particular on designing and
operating the system and extracting this planet from the
data."
McCullough's team found the planet, dubbed X0-1b, by
noticing slight dips in the star's light output when the
planet passed in front of the star, called a transit.
The light from the star, called XO-1, dips by
approximately 2 percent when the planet XO-1b passes in
front of it. The observation also revealed that X0-1b is
in a tight four-day orbit around its parent star.
Although astronomers have detected more than 180
extrasolar planets, X0-1b is only the tenth planet
discovered using the transit method. It is the second
planet found using telephoto lenses. The first, dubbed
TrES-1, was reported in 2004. The transit method allows
astronomers to determine a planet's mass and size.
Astronomers use this information to deduce the planet's
characteristics, such as its
density.
Despite being over ten
years old now, SOHO just keeps on working, monitoring
the activity on the Sun and allowing scientists to see
inside the Sun by recording the seismic waves that
ripple across the surface of our nearest star. 
