The search for Earth 2.0 just got more serious. NASA has teamed up with MIT scientists to expand the search for planets beyond our solar system. The mission's primary goal: identify terrestrial planets in the habitable zone of their parent stars – the region surrounding a star where it is possible for a planet to harbor liquid water (and maybe even life).
The Transiting Exoplanet Survey Satellite (a.k.a. "TESS") will detect planets by scanning for dips in brightness as orbiting bodies pass between their stars and the satellite's line of sight (see the GIF below for an example). Astronomers call this the "transit method." It's the same technique used by Kepler (NASA's current planet-hunting mission), with one big difference: Kepler only scans a small portion of the sky; TESS is designed to survey all of it.
"TESS will carry out the first-ever spaceborne all-sky transit survey, covering 400 times as much sky as any previous mission,” said George Ricker, a senior research scientist at MIT’s Kavli Institute for Astrophysics and Space Research and principle investigator on the project, in a statement. TESS was recently selected as the big winner in NASA's Explorer Program, and will receive up to $200 million dollars from the Agency. “It will identify thousands of new planets orbiting a broad range of stellar types," said Ricker, "and with widely varying distances from their host star."
The mind reels to imagine the discoveries that lie ahead for TESS (concept art pictured above); after all, Kepler may be designed to survey just one small corner of the Milky Way, but in four short years it's managed to revolutionize the field of exoplanet research. Kepler is damn good at its job – and at the rate it's finding planets, most astronomers agree the current planet-hunting mission is close to discovering its first Earth twin (assuming it hasn't found it already). But by expanding the range of sky surveyed, TESS stands to take the search for extrasolar planets and crank it right up to 11.