Chris Peterson wrote:Case wrote:thatsciencedude wrote:Would this region be able to harbor life or is it too hot and chaotic ?
The massive stars may be too short-lived to develop life, even if the radiation is within acceptable levels. Smaller, longer living stars are better candidates.
That said, there are a lot of low mass stars in the same region. The high star density isn't promising for stable planetary systems, but... the evidence suggests that life formed on Earth almost as soon as it was cool enough for liquid water to exist on the surface. To the extent we can utilize a sample of one, life may form easily. If so, there could be a lot of life in systems like this, it's just not likely to be a stable enough environment for life to evolve to the sort of complexity we've had on Earth for the last billion or so years. But there was a long time before that where pond scum was doing extremely well.
I think there were a lot of things that contributed to making the Earth so incredibly suitable for life for such a long time. Personally, I believe that G-type main sequence stars are better suited to hosting planets with life than tiny little M-type stars. That is because the habitable zone is relatively far away from the G-type main sequence star, so that solar outbursts need not be catastrophic for surface-dwelling life forms on a planet in the habitable zone. For red dwarf stars, the habitable zone is so close to the star that any stellar outbursts may be catastrophic for beings in the little red star's habitable zone.
I think there are many other things that have contributed to the Earth being so perfect for life. The Sun is a single star, and while that may not be of critical importance, I believe it helped. The orbits of the other planets are mostly quite round and "stable" (they are not really stable, but they are round and regular enough to appear stable). The Earth has remained at moderately the same temperature for billions of years, and it has had large oceans for most of its existence. When the Earth froze over, life was so well established in the oceans that it could survive under the ice cover. Also the Earth has had plate tectonics for billions of years, which has helped recycle and renew the terrestrial surface. Plate tectonics has also helped drive evolution and encourage the emergence of new life forms.
The Sun is fated to evolve into a red giant and destroy life on Earth in a few billion years. The small red dwarfs, by contrast, are likely to "calm down", and then they will settle into an incredibly long middle age span. It is certainly possible that red dwarfs are the perfect hosts of life in the long run. But I doubt that the universe is old enough for life to have emerged yet on very many planets in orbits around red dwarf stars.
Ann
NGC 6357: Stellar Wonderland
