X-ray Nova Sco 1994, a candidate black-hole binary, has recently been shown to have a heliocentric radial velocity of $-155\pm 10$ km s$^{-1}$. After correction for the Sun's peculiar motion and differential Galactic rotation, the magnitude of Nova Sco's space velocity stands out as being much higher than that of any other dynamically identified Galactic black-hole candidate. If X-ray Nova Sco 1994's velocity is the result of an asymmetry during the initial collapse of its compact object, as is probably the case for neutron stars, this provides an important clue on the formation of its black hole. It most probably suggests that the black hole did not form as a result of a prompt collapse but via an intermediate neutron-star stage and was converted into a black hole by the subsequent accretion of matter or a phase transition in the cooling compact object. We also consider other methods by which Nova Sco could have acquired its high space velocity, but find all of them unattractive.
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