[_justinfunk]

I'm not being snotty. What is the fixed point from which they are measuring the speed? Is the object moving 1M mph relative to earth? The black hole at the center of Milky Way?

[gambiting]

>> What is the fixed point from which they are measuring the speed?

Rest of the milky way galaxy, presumably, given that it talks about escape velocity from it.

[ianburrell]

The paper says the Galactic rest frame.