Last summer, Neil deGrasse Tyson made fun of David Charbonneau's "kind of puny" off-the-shelf telescopes in a trip to the top of Arizona's Mt Hopkins for NOVA scienceNOW. But no one is laughing now: Charbonneau and his puny scopes just discovered a hot, wet super-Earth, a steamy, 400-degree Fahrenheit sauna of planet that brings us even closer to spotting a planet like Earth elsewhere in the cosmos.The new world is about 6.6 times as massive and 2.7 times as wide as the Earth. That's closing in on "Earthlike" territory, thanks to Charbonneau's unconventional approach of searching thousands of small, dim stars called M dwarfs for little dips in brightness. When those dips come at perfectly regular intervals--in this case, every 1.58 days--they are probably caused by the shadow of an orbiting planet.
So how do we know that the new planet has water? It's an educated guess based on the planet's density. But because the planet and its star are so close to Earth--a measly 40 light years away, which is basically around the block--scientists may be able to confirm their suspicions soon using more powerful telescopes.
In the search for planets like Earth, this water world is probably just the tip of the iceberg. (Or should I say water-berg? Maybe Earth-berg? You get the idea.) As Charbonneau's M dwarf survey and new space missions like Kepler hit their stride, scientists are optimistic that they will be turning up increasingly Earth-like planets. Or, as astrophysicist Alan Boss put it in Dennis Overbye's piece in the New York Times: "Give them a couple more years and they're going to knock your socks off."
Note: Kudos to graduate student Zachory Berta, who first spotted the signal from the planet's shadow.
Obligatory artist's conception: David A. Aguilar, CfA
