There are two different coordinate systems:

1. Right Ascension-Declination

Right ascension is analogous to longitude and is measured in hours, minutes, and seconds, from the point of vernal equinox

Measurements of declination are either positive (north) or negative (south).

Note: 1 hour = 15° of arc (1° arc is equivalent 1° of longitude) and 1 minute = 1/60 of an hour, or 0.25° of arc

Example: Proxima Centauri has a declination of -62°40’ (the negative indicates it is located 62° below the celestial equator) and a right ascension of 14h 29.7m

2. Altitude-Azimuth

Altitude is the angular distance, measured from 0 to 90 degrees, of a celestial object above the observer’s horizon. Azimuth is the compass angle from due N to the location of the celestial object

	Criado por Mobeen Ramzan quase 6 anos atrás

FIrst Note

Note 1: The Night Sky