Radial velocity Radial velocity The radial velocity of an object with respect to a given point is the rate of change of the distance between the object and the point. That is, the radial velocity is the component of the object's velocity that points in the direction of the radius connecting the object and the point. In astronomy, the point is usually taken to be the observer on Earth, so the radial velocity then denotes the speed with which the object moves away from or approaches the Earth. In astronomy, radial velocity is often measured to the first order of approximation by
It Must Be Christmas Like Nashville" wrote a positive review in which he praised Young's "classic approach" to the holiday fare. "Whether it be a "New" classic or an evergreen one," he writes, "Young hits all the right notes on the album." Upon release, "It Must Be Christmas" debuted in the top five of the "Billboard" Top Country Albums chart at number four and also topped the Holiday Albums chart. The album has sold 74,100 copies in the US as of November 2017. It Must Be Christmas It Must Be Christmas is the sixth studio album and first Christmas album by American country music