One amusing conversation today was between Ben Pope (NYU) and myself about whether hot stars are more or less likely to host planets with live. We believe (it's not extremely well established yet) that there are more habitable planets around M-type stars than G-type (and there is probably a relatively smooth function of temperature). So why do we live around a G star? Is it because there is more free energy per photon? I have assumed that this is why. But we realized that we can make this argument quantitative. One question that I have is this: Is this argument anthropic? Or is it just the simple observation that Earth hosts life? I think it is anthropic, because it has something to do with whether our place is special.
I might hypothesize the other way around (disclaimer, I work on galaxies, not planets). Hab zones of G stars are bigger, and more importantly, zones for planets like Jupiter farther out. Jupiter does a great job of clearing things out in our solar system, but for an M star, I would imagine things could get dicey. My money is on how the system forms its planets and settles on timescales commensurate with biology
ReplyDelete