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
To Be a Pilgrim To Be a Pilgrim "To Be a Pilgrim" (also commonly known as "He who would Valiant be") is the only hymn John Bunyan is credited with writing, and is indelibly associated with him. It first appeared in Part 2 of "The Pilgrim's Progress", written in 1684. The hymn recalls the words of Hebrews 11:13: "...and confessed that they were strangers and pilgrims on the earth." The words were modified extensively by Percy Dearmer for the 1906 "The English Hymnal". At the same time it was given a new tune by British composer Ralph Vaughan Williams, who used a melody taken