Glossary

From Stellarium

This is a glossary of terms used in Stellarium. If there are any terms used in the software or user guide which you think require further explanation, please add them here. Similarly if you know the proper definition of a term which is listed by has no definition, please add that. Note - please keep this list in alphabetical order.

Apparent magnitude (m) 

A measure of the brightness of a star or other heavenly body as it appears from a given point (e.g. from an observer's location).

Equinox of date 

(Appears as "Equ of date" in Stellarium.) The equatorial coordinate system is continually sliding around due to a slow shift in the orientation of the Earth's axis with respect to the rest of the universe. Because of this, the right ascension and declination of a star are continually changing. When the right ascension and declination are given for the "equinox of date," as they are often given for moving objects, it means that they are correct for the actual date. (A better definiton is welcome… --Mayday 02:50, 11 December 2007 (PST))

Light year 

A measure of distance defined as the distance which light can travel is one year. See also Parsec.