Space Journal Entry
Space Journal Entry
Astronomers Find Rocky Exoplanet (September 21, 2009)
Artist's impression of the view from Corot-7b, the recently discovered rocky exoplanet. European Southern Observatory.
European astronomers say they've found the first confirmed rocky exoplanet, or planet beyond our solar system. The exoplanet named Corot-7b has a density close to that of Earth, strong evidence it's solid and not a gas planet. Its diameter is about 1.5 times as large as Earth's. Corot-7b orbits a star 500 light-years from our home planet. A light-year is the distance light travels in one year, or roughly six trillion miles (10 trillion km).
The exoplanet's orbit is only 1.6 million miles (2.6 million km) from its parent star, making it 23 times closer than Mercury is to the Sun. Because its surface temperature is more than 3,600 degrees Fahrenheit (2,000 degrees Celsius), there's no chance of finding water or extraterrestrial life. Its surface is so scorchingly hot it's been nicknamed the "lava planet." The planet zips around its star in just 20 hours at a speed of 466,000 miles per hour (746,000 km/h).
The discovery has created a buzz among astronomers. If there's one rocky, Earth-like planet out there, chances are excellent there are many more. Hopefully, some of these will be found in the habitable zone of their solar system. Such planets would be at just the right distance from their stars to possibly have liquid water and support life.
Earlier this year, NASA launched the Kepler spacecraft on a mission to hunt for exoplanets. The mission is off to a terrific start.
Astronomers discovered the first exoplanet in 1995. They've spotted more than 300 others since. But so far, they've either been too hot, too cold, or too gaseous to support life. Some are gas giants more massive than Jupiter.
