In reply to neilzero's comment:
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Are very young , massive, short lived stars more than 100 solar mass each? It does seem that a cloud of hydrogen of 10,000 solar mass or more, should be detectable by some means. Perhaps the last of these hydrogen clouds close to the galactic center became stars a few centuries ago? Neil
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Hi Neil,
There appears to be agreement that a gas cloud of sufficient density could not have formed at that location. Also as noted below there appears to be agreement that the massive young stars could not have migrated to their current locations. (MM is a European abbreviation for a million. As noted below a star of 15M⊙ has a life of approx. 40 million years.)
The following is another excerpt from the galactic center review paper (see above for a link.)
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The young stars are also too short-lived and too light to have formed far from the Milky Way’s black hole, where the tidal field is weak, and then to have migrated in by dynamical friction. The “collection basin” for the migration of young MS stars of mass of M⋆ =15M⊙ and lifespan t⋆ =2×10^7 yr is only maxrdf ∼ 0.2pc, and for stars of mass M⋆ =3M⊙ and lifespan t⋆ =4×10^8 it is only maxrdf ∼0.5pc.
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The unavoidable conclusion is that if the young stars well inside the central parsec were formed locally, then they must have done so by a different mechanism than the collapse of self gravitating cold molecular gas clouds that occurs in normal star forming regions.
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