Kepler spacecraft article from the New York Times
Thursday, March 05, 2009
Okay, one more post on Kepler before it launches. I wasn't going to write another one but I like how this article begins:
Someday it might be said that this was the beginning of the end of cosmic loneliness.Being the New York Times it also has a nice graphic.
And:
There the spacecraft’s mission will be to discover Earth-like planets in Earth-like places — that is to say, in the not-too-cold, not-too-hot, Goldilocks zones around stars where liquid water can exist.The job, in short, is to find places where life as we know it is possible.Almost as exciting of course would be planets that we suspect were likely places for life but have since grown too hot / lost much of their atmosphere or for some other reason can't sustain life anymore. Something like Venus for example but not quite on the same scale, where any life that did exist would probably still be able to be found as fossils (well, when we finally achieve the technology necessary to get there that is).
I have a bit of an issue with this part:
To detect something as small as the Earth, the measurements need to be done with a precision available only in space, away from the atmospheric turbulence that makes stars twinkle, and far from Earth so that our home world does not intrude on the view of shadow worlds in that patch of sky. It will take three or more years — until the end of Barack Obama's current term in office — before astronomers know whether Kepler has found any distant Earths.because this is assuming we're not only talking about Earth-like planets but also Earth-like planets around stars similar to our Sun. It's more probable that the first Earth-like planets Kepler will find will be around red dwarf stars, because:
1) They're much smaller, making the dimming as the planet passes in front that much greater in scope, and
2) To be within a red dwarf's habitability zone a planet usually ends up with an orbit of only a few weeks; 15 days or so. That means that instead of three or more years, detecting a planet around a red dwarf at that range will only take two months.
So assuming everything goes as planned I expect that during the first few years of Kepler's observations we'll see planet after planet discovered around red dwarfs, and during that time that's what the discussion will centre on - whether planets around red dwarfs would be able to sustain life, and if so what it would look like.
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