| Revision as of 08:01, 30 July 2003 editFransvannes (talk | contribs)Extended confirmed users1,237 editsmNo edit summary← Previous edit | Revision as of 01:04, 2 August 2003 edit undoLooxix~enwiki (talk | contribs)6,016 editsm interlanguage linksNext edit → | ||
| Line 1: | Line 1: | ||
| ] | ] ] ] | ||
| '''Right ascension (RA)''' is an ] term associated with the ]. RA is comparable to longitude, measured from a zero point known as the ''']'''. RA is measured in hours, minutes, and seconds; with one hour equal to 15 degrees. | '''Right ascension (RA)''' is an ] term associated with the ]. RA is comparable to longitude, measured from a zero point known as the ''']'''. RA is measured in hours, minutes, and seconds; with one hour equal to 15 degrees. | ||
Revision as of 01:04, 2 August 2003
Right ascension (RA) is an astronomical term associated with the equatorial coordinate system. RA is comparable to longitude, measured from a zero point known as the vernal equinox point. RA is measured in hours, minutes, and seconds; with one hour equal to 15 degrees.
RA can be used to determine a star's location and to determine how long it will take for a star to reach a certain point in the sky. For example, if a star with RA = 01:30:00 is at your zenith, then a star with RA = 20:00:00 will be directly overhead in 18.5 sidereal hours.
See also: declination