1) There is no quasar at the center of the Milky Way (There is, however, a massive black hole).

2) In most cases, gravitational redshift is negligible except near a black hole (30,000 light years - our distance from the center of the Milky Way - is not close) or neutron star. When necessary, it is easy to factor it into the equations.

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Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson