= 27d567bc2d48d9f40e9ccc20ea370b15)
Nornagest comments on Open thread for December 9 - 16, 2013 - Less Wrong Discussion
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (371)
Is that a relevant number?
Doesn't the relevant number of opportunities for life to appear have units of mass-time?
Isn't the question not how early was some Goldilocks zone, but how much mass was in a Goldilocks zone for how long? This says that the whole universe was a Goldilocks zone for just a few million years. The whole universe is big, but a few million years is small. And how much of the universe was metallic? The paper emphasizes that some of it was, but isn't this a quantitative question?
We should have the data now to take a whack at the metallicity side of that question, if only by figuring out how many Population 2 stars show up in the various extrasolar planet surveys in proportion with Pop 1. Don't think I've ever seen a rigorous approach to this, but I'd be surprised if someone hasn't done it.
One sticking point is that the metallicity data would be skewed in various ways (small stars live longer and therefore are more likely to be Pop 2), but that shouldn't be a showstopper -- the issues are fairly well understood.
The paper mentions a model. Maybe the calculation is even done in one of the references. The model does not sound related to the observations you mention.