Canis Major
Canis Major is a prominent constellation because of its many bright stars. These include Sirius (Alpha Canis Majoris), the brightest star in the night sky, as well as three other stars above magnitude 2.0. Furthermore, two other stars are thought to have previously outshone all others in the night sky—Adhara (Epsilon Canis Majoris) shone at -3.99 around 4.7 million years ago, and Mirzam (Beta Canis Majoris) peaked at −3.65 around 4.42 million years ago. Another, NR Canis Majoris, will be brightest at magnitude −0.88 in about 2.87 million years' time.
Betelgeuse
Betelgeuse is a variable star whose brightness ranges between 0.0 and 1.3. There are periods when it will surpass Rigel to become the sixth brightest star, and occasionally it will be even brighter than Capella. At its faintest Betelgeuse can fall behind Deneb and Beta Crucis, themselves both slightly variable, to be the 20th-brightest star.