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Re: APOD: The Coldest Brown Dwarf (2011 Aug 30)

Posted: Wed Aug 31, 2011 4:53 am
by Chris Peterson
jackkessler wrote:While this discussion is interesting it is beside the point. A considerably more interesting question is not whether human being could survive on the surface of a brown dwarf, but whether viruses or even bacteria could. The effects of gravity on creatures at that scale is insignificant on earth. Would they be able to endure on a brown dwarf? Or to evolve there in the first place?
While I'm sure a nice science fiction scenario could be constructed, who can really know? The only place in a cold brown dwarf that would be remotely habitable to anything we currently understand as life would be a thin layer of the upper atmosphere. But presumably the atmosphere is convective over a much greater zone, which means that a scenario where life could exist seems difficult to construct.
I am not impressed with the radiation argument. We live near a star that produces vastly greater amounts of vastly more energetic radiation and we do just fine with it. The surface would be shielded from thermonuclear processes in the core by the entire radius of the brown dwarf.
That's not necessarily very good shielding. We are protected by Earth's magnetic field; without that, there would be little or no life on Earth. No such protection exists at the top of the atmosphere of a brown dwarf.

Re: APOD: The Coldest Brown Dwarf (2011 Aug 30)

Posted: Wed Aug 31, 2011 2:22 pm
by geckzilla
I don't know how people surviving is anymore beside the point than bacteria surviving. Both questions were posed because the temperature of the dwarf seems quite nice. But, yes, let's get wildly imaginative here and speculate that at the height of this "bacterial" evolution, they could all connect to each other like neurons and transform the brown dwarf into one giant brain.

Re: APOD: The Coldest Brown Dwarf (2011 Aug 30)

Posted: Wed Aug 31, 2011 5:27 pm
by rstevenson
jackkessler wrote:If a microbiota could exist there, while it is unlikely that large talking apes such as ourselves would arise, evolution in entirely other directions might well take place.
Flatland!

Rob

Re: APOD: The Coldest Brown Dwarf (2011 Aug 30)

Posted: Thu Sep 01, 2011 8:15 pm
by alter-ego
rstevenson wrote:
jackkessler wrote:If a microbiota could exist there, while it is unlikely that large talking apes such as ourselves would arise, evolution in entirely other directions might well take place.
Flatland!

Rob
Good one!

Re: APOD: The Coldest Brown Dwarf (2011 Aug 30)

Posted: Tue Sep 20, 2011 7:42 am
by Dave
Thank you for the food for thought, especially jackkessler and John Olson - I must read "The Integral Trees" sometime...