On Sep 2, 10:48*am, Sam Wormley wrote:
On 9/2/12 12:40 PM, Brad Guth wrote:

Could an existing solar system like ours capture a red dwarf without
causing too much trauma for the existing planets?

* *If the sun encountered another star (say a red dwarf) the Keplerian
* *orbit of each would be hyperbolic for each star and the encounter
* *would be one time. Capture requires, perhaps a third star or transfer
* *of momentum via drag. So it very unlikely that our sun would capture
* *a red dwarf.

I can agree with that, although the nearby encounter with Sirius might
not count as a capture of our solar system by the superior mass of
Sirius, and yet it certainly could represent a cosmological cycle of
an encounter worthy of melting the last portions of ice on Earth.

However, if the encounter with a red dwarf included its lithobraking
via Saturn or Jupiter, as such could allow for the capture. There are
computer simulators that'll help demonstrate this and other possible
methods of our solar system capturing another sun, or that of our
solar system being captured by something else.