# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Astro*Dictionary by Michael Erlewine





2 articles for "Absolute"

Absolute Longitude [Astro*Index]

Also called Celestial Longitude. Absolute longitude is the degree distance along the ecliptic measured from the vernal point or 0° Aries tropical. Either zodiac (12 signs of 30 degrees each) or 360° notation is used. Fractions of a degree are expressed either in minutes and seconds of arc (hexagesimal) or as decimal portions. Absolute longitude can be calculated either from a heliocentric or geocentric perspective.

See also:
♦ Ecliptic ♦ Vernal Point ♦ Heliocentric ♦ Geocentric
Absolute Magnitude [Astro*Index]

Absolute magnitude is the actual brightness of a star: how bright it would appear if it were at a standard distance of 32.6 light years. Our Sun's absolute magnitude is +4.9. The most luminous star, known as S Doradus, has an absolute magnitude of about -8.9. The faintest dwarf stars have a magnitude of about +21.

See also:
♦ Magnitude ♦ Apparent Magnitude ♦ Luminosity ♦ Dwarf Nova


Astro*Index Copyright © 1997 Michael Erlewine