By Marc Kaufman / Wahington Post
New discoveries from NASA’s Kepler space mission made public Wednesday reveal a large and surprising menagerie of planets deep in space, with some almost as small as Earth and others in the “habitable zones” of their solar systems where scientists think life could potentially exist.
With about 1,200 candidate planets now catalogued, Kepler has also identified a solar system with at least six small planets orbiting their sun – all lined up on a disc-like plane similar to our own.
The planets – called exoplanets because they are outside the Earth’s solar system – are believed to be gaseous rather than rocky and so unable to support life, but the discovery of a system with so many planets and all orbiting in a manner similar to planets in our system has created great excitement.
“This is a remarkable system and a very exciting sign of what else is to come,” said Jonathan Fortney, a member of the Kepler science team from the University of California at Santa Cruz.
“Given the information Kepler is sending back, we’re not only able to identify the planets, but we can tell a lot about how big they are, how close they are to their suns and to some extent what they’re made of,” he said.
The results released at a NASA press conference and the journal Nature report on a little more than a quarter of the information already collected by Kepler, launched almost two years ago.
The unprecedented job of the space telescope is to observe a small section of deep space to determine how many Earth-sized planets exist there, how many suns like our own have planets, and how many of those planets might be in habitable zones. The ultimate goal is to assess whether some planet can, or even do, support life.
Because of the technique used by Kepler to find the exoplanets, those identified so far are usually closer to their suns than Mercury is to our sun, with orbits of a few months to a few days. As Kepler collects information over a longer time, planets further from their suns will be identified and those are the ones expected to be the rocky, watery and potentially more hospitable to life.