Apparent magnitude of well-known stars and other heavenly bodies

In the second century B.C., the Greek astronomer Hipparchus arranged the stars in six grades or classes, of brightness, or apparent magnitude. (As applied to a star, the word "magnitude" has to do with brightness and not with size.) The brightest stars were put in the first grade, the next brightest stars in the second grade and so on. Hipparchus' classification was adopted and improved by Ptolemy of Alexandria in the second century A.D. Our present system of apparent magnitudes is based on the work of these men, though the light values assigned to the different magnitudes have been greatly refined. In the case of the heavenly bodies that are brighter than the stars of the first magnitude, each increasing stage of brightness above 1 is indicated by the appropriate numeral (0, 1, 2, 3 and so on) preceded by a minus sign.

• Sun —26.7
• Moon —12.5 at brightest
• Venus —4.3 at brightest
• Mars —2.8 at brightest
• Sirius A —1.5
• Júpiter —1.3
• Canopus -0.9
• Alpha Centauri A 0.33
• Vega 0.1
• Capella 0.2
• Arcturus 0.2
• Rigel 0.3
• Procyon A 0.5
• Betelgeuse 0.9 (variable)
• Altair 0.9
• Saturn 1.
• Mercury 1.
• Aldebaran 1.1
• Antares 1.2
• Spica 1.2
• Pollux 1.2
• Fomalhaut 1.3
• Deneb 1.3
• Regulus 1.3
• Castor 1.6
• Bellatrix 1.7
• Mira Ceti 2.2 (variable)
• Shedir 2.3
• Polaris 2.3 
• Mizar 2.4
• Alcyone 3.
• Alcor 4.
• Uranus 6.