posted 06-14-2005 06:38 AM
Taking a major step forward in the search for Earth-like planets beyond our own solar system, a team of astronomers has announced the discovery of the smallest extrasolar planet yet detected. About seven-and-a-half times as massive as Earth, with about twice the radius, it may be the first rocky planet ever found orbiting a normal star not much different from our Sun. The newly discovered "super-Earth" orbits the star Gliese 876, located just 15 light years away in the direction of the constellation Aquarius. Gliese 876 is a small, red star known as an M dwarf--the most common type of star in the galaxy. It is located in the constellation Aquarius, and, at about one-third the mass of the sun, is the smallest star around which planets have been discovered. This star also possesses two larger, Jupiter-size planets.
The new planet whips around the star in a mere two days, and is so close to the star's surface that its dayside temperature probably tops 400 to 750 degrees Fahrenheit (200 to 400 degrees Celsius)--oven-like temperatures far too hot for life as we know it
The team measures a minimum mass for the planet of 5.9 Earth masses, orbiting Gliese 876 with a period of 1.94 days at a distance of 0.021 astronomical units (AU), or 2 million miles.
Abstracted and edited from a National Science Foundation news release of 13th June 2005
Phill
UK