Sidereal Hour Angle
The sidereal hour angle of a body on the celestial sphere is its angular distance west of the vernal equinox generally measured in degrees. The SHA of a star changes slowly, and the SHA of a planet doesn't change very quickly, so SHA is a convenient way to list their positions in an almanac. SHA is often used in celestial navigation and navigational astronomy.
Read more about this topic: Hour Angle
Famous quotes containing the words sidereal, hour and/or angle:
“Perhaps our eyes are merely a blank film which is taken from us after our deaths to be developed elsewhere and screened as our life story in some infernal cinema or despatched as microfilm into the sidereal void.”
—Jean Baudrillard (b. 1929)
“He conveys the least information, even the hour of the day, with such magnificence and vast expense of natural imagery, as if it were a message from the gods.”
—Henry David Thoreau (1817–1862)
“So much symmetry!
Like the pale angle of time
And eternity.
The great shape labored and fell.”
—N. Scott Momaday (b. 1934)