- #1
magic9mushroo
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(I honestly don't know whether this is Intermediate or Advanced. I'm guessing the latter since I don't know the answers and I've done second year astrophysics, but maybe I'm just an idiot.)
Let's say you've got a high mass (~60 Jupiter masses) brown dwarf in relatively close orbit around a true star. Let's further say that it's an F or G star that eventually climbs the Red Giant Branch.
1) Can that actually happen, or is there some effect that forbids it?
If the brown dwarf is in a close enough orbit, it will presumably be engulfed by the expanding envelope of its companion.
2) Is a brown dwarf's gravity sufficient to accrete matter from a red giant envelope, or would it ablate?
3) Presumably the drag from the envelope would cause the brown dwarf's orbit to inspiral. Over what sort of timescale would that occur?
4) If the brown dwarf would, in fact, accrete, is it possible for that accretion to ignite fusion? Could it happen before the inspiral caused it to merge with the star's inner layers?
5) If it did ignite, what would the result be? Would it become a red dwarf star in its own right, or would it explode in a runaway reaction like that in a type-Ia supernova? Or would there be some other result?
Thanks in advance.
Let's say you've got a high mass (~60 Jupiter masses) brown dwarf in relatively close orbit around a true star. Let's further say that it's an F or G star that eventually climbs the Red Giant Branch.
1) Can that actually happen, or is there some effect that forbids it?
If the brown dwarf is in a close enough orbit, it will presumably be engulfed by the expanding envelope of its companion.
2) Is a brown dwarf's gravity sufficient to accrete matter from a red giant envelope, or would it ablate?
3) Presumably the drag from the envelope would cause the brown dwarf's orbit to inspiral. Over what sort of timescale would that occur?
4) If the brown dwarf would, in fact, accrete, is it possible for that accretion to ignite fusion? Could it happen before the inspiral caused it to merge with the star's inner layers?
5) If it did ignite, what would the result be? Would it become a red dwarf star in its own right, or would it explode in a runaway reaction like that in a type-Ia supernova? Or would there be some other result?
Thanks in advance.