M dwarfs. Astronomers tend to believe that these stars put out too little light to support life on any planets that orbit them. However, at a recent workshop held at the SETI Institute, a multidisciplinary group of researchers concluded not only that M dwarfs might host habitable planets, but that they might also be good targets in the search for extraterrestrial intelligence.
Personally, I'm a bit skeptical. I'm inclined to invoke the self-sampling assumption and hypothesize that we've got the Goldilocks star: not to hot, not too cold, not too big, not too small -- just right for life and intelligence to ignite and evolve. The type of heat, light, and radiation emitted from M Dwarfs may be just out of the habitable spectrum.
Tags: Fermi Paradox, Life on Other Planets, Astrobiology, Astronomy, SETI.