Work on astronomy largely ground to a halt this morning as the Decadal Review was published outlining the direction the field should take over the next 10 years. With so many bright ideas floating around in astronomy, it can be hard to pick out the most interesting questions and the projects most likely to answer those questions. So every 10 years, the nation's astronomers come together to take a look at the big picture, and to look to the future.
The report starts by looking back at the dramatic progress made in the past few years. It's hard to believe that a mere 20 years ago, we had no idea that dark energy existed, or whether planets existed around any star in the Galaxy other than our own.
But while we've climbed some impressive scientific mountains in the past twenty years, there are even more impressive peaks on the trail ahead. The Decadal Review considers “the most profound discovery in the coming decade may be the detection of potentially habitable Earth-like planets orbiting other stars”. People have dreamed of that day ever since the times of the ancient Greeks.
This goal has two steps. First we need to find Earth-sized planets at just the right distance from their parent star, and then we will need to develop new technology to probe their atmospheres to search for oxygen, nitrogen, and the other elements we expect to find on a habitable, Earth-like, planet.
The second task is extraordinarily difficult. Earth-sized planets are small, far away, and hidden in the glare of their parent stars. A lot of development is still needed to build instruments to overcome those problems. Despite the challenges, the review places the challenge of imaging a habitable planet as a "Priority 1" goal, and Kepler as a key mission along the way.
In the meantime, Kepler is already hard at work answering the first question. Staring, unblinking, at 170,000 stars day after day, it will detect a minute change in brightness when a planet passes in front of the star it orbits. Before the decade is even half over, we hope to have found the first Earth-sized planet, and also to discover if such planets are commonplace, or rare.
The Decadal Review is mostly a dry, academic document with careful phrases and important caveats, but it rises to more poetic language when it attempts to describe the importance of this work. Hopefully, "one day, parents and children could gaze at the sky and know that a place somewhat like home exists around 'THAT' star". That day (or night!) is probably still more than a decade away, but it's an awful lot closer than it was ten years ago. And so, here on the Kepler Team, we're putting down our Decadal Reviews, and getting back to the work of bringing that day a little nearer.
For more information on the recently released 2010 Astronomy & Astrophysics Decadal Survey Report:
New Worlds, New Horizons in Astronomy and Astrophysics, National Academies Press
by Fergal Mullally
Support Scientist for the Kepler Science Analysis Systems
Kepler Science Office, NASA Ames Research Center