Comments on: Rouge Planet.

By: Hentzau

Hentzau — Fri, 16 Nov 2012 17:56:20 +0000

Possible, but unlikely. Planets eventually migrate to stable orbits thanks to resonances etc, but a new planet that took up even temporary residence in the solar system — especially one four time the size of Jupiter — would have a dramatically destabilising effect on the rest of them. While it might be theoretically possible for a rogue planet to be captured and assume a stable orbit, the solar system would undoubtedly lose others, very probably including the Earth since it’s the smaller planets that get chucked first.

By: Smurf

Smurf — Fri, 16 Nov 2012 11:53:52 +0000

Can a rogue planet be captured by another system and then not be a rogue planet anymore? Like, would it be possible for our Sun to capture a rogue planet and give us another planet in our solar system?

By: Gap

Gap — Thu, 15 Nov 2012 14:53:25 +0000

Here’s a paper on simulations of star formation in molecular clouds, which has quite a nice model for the origins of the initial mass function: http://arxiv.org/abs/1110.1092

I think the bottom of the IMF is pretty open, still; small things tend to be harder to resolve than big things. But I’m sure that Kroupa review has all the information you could possibly ever not want to read.

By: Hentzau

Hentzau — Thu, 15 Nov 2012 14:44:42 +0000

Oh, now that is interesting. So it’s basically saying that if this rogue planet/brown dwarf/whatever formed on its own its very much an outlier rather than the status quo? That makes sense given that they only found one in the entire survey, although obviously what you can see in astronomy isn’t necessarily the same as what is there.

By: Gap

Gap — Thu, 15 Nov 2012 14:07:18 +0000

Also your bad spelling mars an otherwise excellent post or whatever.

By: Gap

Gap — Thu, 15 Nov 2012 14:06:33 +0000

So I found this epic review paper on the IMF (http://arxiv.org/abs/1112.3340), and one of the things that it brings up is that it’s quite difficult for very small stars/brown dwarfs to form without a host star, because it requires that the core of the protostar is ejected almost instantly from the molecular cloud before it can accrete anything. Not that they don’t exist, of course. Also, yeah, the attempt to reproduce the IMF in simulations of molecular clouds are pretty neat, and mainly serves to underline how messy and complicated astrophysics can be.