Comment by rms

I'm very curious to see the preliminary Kepler results announced on the 4th, though I think if they actually found any small rocky planets the results would have leaked already.

My timeline is that Kepler has discovered hundreds of rocky planets in the habitable zones of their suns by 2013. This sets off the public imagination and NASA and friends have the funding to design and launch Kepler Mark II around 2017 though with enough funding it could be faster. Maybe 2023 or 2024 is a more realistic timeline for confirming a planet's habitability to >95%.

http://www.npr.org/templates/story/story.php?storyId=1014934... refers briefly to a potential type of oxygen, CO2, water, and methane detecting telescope.

As for the stretch goal, maybe Alpha Centauri does have life. If it does have a potentially habitable planet, we are definitely going to know within five years. http://seedmagazine.com/content/article/the_long_shot/