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abstraction > mathematical concept > number > quantity > velocity > galactic velocity component > V velocity

V velocity comparison table

Subject	is a kind of	has definition
galactic velocity component	velocity	One of three components of a star's motion with respect to the center of a galaxy.
V velocity	galactic velocity component	A star's velocity in the direction of Galactic rotation, as measured relative to a nearby star that has a circular orbit. If a star revolves faster than such a star, the V velocity is positive; if it revolves more slowly, the V velocity is negative; and if both revolve at the same rate, the V velocity is zero. The Sun has a V velocity of +12 kilometers per second, so it revolves 12 kilometers per second faster than it would if it had a circular orbit. Since a star on a circular orbit revolves around the Galaxy at 220 kilometers per second, a star with a V velocity of 0 is not stationary; rather, it revolves at 220 kilometers per second. The Sun therefore revolves around the Galaxy at 220 + 12 = 232 kilometers per second.

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