Star Brighness (Planets at maximum) Handboook of the BAA: Sun -26 Moon -12 Venus -4.4 Mars -2.9 Jupiter -2.5 Saturn -1 Uranus 5.7 Neptune 7.8 Pluto 14 Norton's 2000 Star Atlas and Reference Handbook: Sirius (alpha Canis Major) - 1.5 Canopus (alpha Carina) - 0.7 Arcturus (alpha Bootes) - 0.04 Vega (alpha Lyra) +0.03 capella (alpha Auriga) 0.08 Rigel (beta Orionis) 0.12 Betelgeuse (alpha Orionis) 0.5 Aldebaran (alpha Tau) 0.85 Spica (alpha Virgo) 1.0 Caster (alpha Gem) 1.6 Visible stars in telescope or binoculars (Sidgwick, Amataur Astronomer's Handbook) Objective or Mirror diameter in cm. Magnitude 5 10.5 10 12.0 15 12.9 20 13.5 25 14.0 30 14.4