Well, it's official: the Kepler planet-finding telescope is out of business. Its attitude control wheels aren't working with the precision needed to keep the spacecraft aimed properly, so it's no longer capable of looking for planets beyond the Solar System. It's still a functional telescope, and NASA's now shopping around looking for a new mission. Anybody need a space telescope?
The sad thing is that the spacecraft failed just when things were getting interesting. Kepler discovered a whole lot of extrasolar planets -- 134 confirmed planets and a whopping 3,277 possibles. It's that second number which makes the end of the mission so frustrating. Just a few more years of operation would have allowed astronomers to nail down more of those potential planets, and get a better sense of what sort of worlds are out there.
Anyone who's been following the exoplanet news knows that astronomers have found a lot of weird worlds out there: gas giants as big as Jupiter orbiting their parent stars closer than Mercury circles the Sun, or "Super-Earths" which are apparently solid worlds many times the size of the Earth. What they haven't really found are "normal" planets like those in our own system.
The problem is that planets move slowly. They orbit with periods of months or years (if not centuries). The Kepler telescope could only sense planets when they passed in front of their parent stars, which means that we only got a look at each world once in its year. That's why we know so much about the freaky close-orbiting planets: they've had many "years" in the four years Kepler was operating. But the worlds with wider, slower orbits haven't had the chance for a second appearance yet, and now they never will.
I don't know much about the politics of NASA funding, but I do hope someone can find the money for a replacement. Kepler dramatically increased our knowledge of the universe, and it would be a shame to abandon the effort. I know money's tight right now, but maybe the President could skip one vacation trip?
Comments