Big news in the search for planets outside our solar system last week. I’ll try to summarize all the news that came out in one post.
Nasa scientists discover planetary system
Astronomers have discovered a planetary system made up of six planets orbiting a Sun-like star that is more than 2,000 light years from Earth. It is the largest number of planets found so far around a single star.
Jack Lissauer, a scientist at Nasa’s Ames research centre in California and a lead author on a paper published tomorrow in the journal Nature, said that the Kepler-11 finding was “the biggest thing in exoplanets since the discovery of 51 Pegasi B, the first exoplanet, back in 1995″.
The five inner planets of the Kepler-11 system are between 2.3 and 13.5 times the mass of the Earth, and make their orbits in less than 50 days. All of them are so close to their star that their orbits would fit within that of Mercury in our solar system. The sixth planet has an orbital period of 118 days and sits at a distance from its star that is half the Sun-Earth distance. Lissauer said it was unexpected to find a system where planets could be so close to one another and there could be so many of them on such a flat plane. “The Kepler-11 system is flatter than a CD,” he said. “If placed within our solar system, Kepler-11’s six planets would lie between those of the sun’s innermost planets, Mercury and Venus.”
Exoplanet hunt turns up 54 potentially habitable worlds
Astronomers have identified some 54 new planets where conditions may be suitable for life.
Five of the candidates are Earth-sized.
The data release also confirmed a unique sextet of planets around a single star and 170 further solar systems that include more than one planet circling far-flung stars.
Kepler Telescope discovers 1200 new worlds
In fifteen years, astronomers have detected just over 500 planets orbiting other stars. Now, after less than two years in orbit, the Kepler telescope has more than tripled that figure, discovering more than 1,200 possible new worlds. Even better, at least 54 of them are in their star’s habitable zone, and five of these are Earth-sized planets. But here’s the best part – Kepler only looked at one tiny corner of our galaxy. We really might be surrounded by millions of Earth-like planets after all.
Turns out yesterday’s story about a tightly packed solar system was just a tease for the really big news. After just 23 months in orbit, NASA’s Kepler telescope has discover 1,235 potential planets orbiting around the 156,000 stars it’s been charged with observing. It should be stressed that these are still just possible planets, but in all likelihood the vast majority of these observations will stand up, so we’re still probably looking at at least a thousand new exoplanets.
So what sorts of planets has Kepler found? There appear to be 68 Earth-sized planets, 288 rocky planets that are considerably bigger and known as Super-Earths, 662 relatively small gas giants around the size of Neptune, 165 Jupiter-sized planets, and 19 that are even bigger than Jupiter. The discovery of nearly 70 Earth-like planets is particularly exciting, considering we had only detected a handful of them before this.
Definitely exciting times in Astronomy and I wholeheartedly believe this is just the beginning. There’s got to be hundred of thousands of planets our there – if not billions in the entire universe.