Arlington, Va.. 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.Heavy, man. A high-g place, anyway. And too hot for it to be terraformed until we have rather better technology than is required just for getting there in a reasonable time. But it bodes well.
All of the nearly 150 other extrasolar planets discovered to date around normal stars have been larger than Uranus, an ice-giant about 15 times the mass of the Earth.
"We keep pushing the limits of what we can detect, and we're getting closer and closer to finding Earths," said team member Steven Vogt, a professor of astronomy and astrophysics at the University of California, Santa Cruz.
Today's results are an important step toward answering one of the most profound questions that mankind can ask: Are we alone in the universe? said Michael Turner, head of the Mathematical and Physical Sciences Directorate at the National Science Foundation, which provided partial funding for the research.
The newly-discovered super-Earth orbits the star Gliese 876, located just 15 light years away in the direction of the constellation Aquarius. 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 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.
Nevertheless, the ability to detect the tiny wobble that the planet induces in the star gives astronomers confidence that they will be able to detect even smaller rocky planets in orbits more hospitable to life.
Wednesday, 15 June 2005
From Exoplanets.org :