This would be a gas!

Similar Solar System Found Only 90 Light Years Away

July 4, 2003
By DENNIS OVERBYE






A team of British, Australian and American astronomers
announced yesterday that they had found a hint of home 90
light years away in the constellation Puppis.

There, in what they say is the closest resemblance to
Earth's solar system yet found in outer space, a
Jupiterlike planet circles a sunlike star known as HD70642
in an orbit that corresponds to one halfway between Mars
and Jupiter in our own system. The discovery raises the
hopes of planet hunters that if they keep working they will
find more and more potentially habitable systems like our
own.

More than 100 planets have been detected orbiting other
stars in the nearby reaches of our galaxy in the last few
years. Most have been brutes the size of Jupiter, but in
elongated orbits that whiz them around uncomfortably close
to their stars, often inside the distance of Earth to the
Sun. Such planets would be too hot and dense to support
life, and their gravitational effects would chase smaller
potentially habitable planets out of the system.

The new planet has about twice the mass of Jupiter, and is
in a circular, six-year orbit. Perhaps even more
intriguing, there is no evidence of any giant planets
orbiting inward of the new planet, leaving a swath of space
where smaller terrestrial planets could happily and stably
exist.

"This is the closest we have yet got to a real solar
system-like planet, and advances our search for systems
that are even more like our own," said Dr. Hugh Jones of
Liverpool John Moores University in England.

Dr. Geoffrey W. Marcy of the University of California, who
along with Dr. Paul Butler of the Carnegie Institution of
Washington, has pioneered the search for so-called
extrasolar planets, agreed, saying, "This new planet around
HD70642 is by the far the closest analog to our Jupiter
ever found."

Dr. Jones led the international team of astronomers who
made the discovery using a 3.9-meter-diameter
Anglo-Australian Telescope in New South Wales, Australia.
He announced the discovery yesterday in Paris at a
conference, "Extrasolar Planets: Today and Tomorrow."

The team made the discovery by examining the light from
HD70642 for signs of a wobble in its motion away from us.
If a star has a planetary companion, the gravity of the
planet as it circles the star exerts a tug that alternately
speeds and slows the star's motion, imparting a
characteristic shift in the wavelength of its light. The
more massive the planet and the closer it is to its star,
the greater the induced wobble, which is why the more
musclebound systems with close-in planets were discovered
first.

But as observations have continued, astronomers explain,
they have become more sensitive to planets in more distant
orbits. Last year, astronomers reported the discovery of
several Jupiter-size planets at Jupiterlike distances from
their stars.

The new discovery stands out, in part, Dr. Marcy said,
because of its parent star's resemblance to the Sun. The
star HD70642 has the same mass as the Sun, within a few
percent, and nearly the same age, 4.8 billion years, making
it seem even more like a home away from home.

After a decade of searching for new planets, Dr. Marcy
said, "Searching for analogs to our solar system is what
gets me up in the morning."

http://www.nytimes.com/2003/07/04/science/04PLAN.html?ex=1058431844&ei=1&en=e0e5f9e01767d1d8