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.
Historical brightest stars
Working out exactly which stars were or will be the brightest at any given point in the past or future is difficult since it requires precise 3D proper motions of large numbers of stars and precise distances. This information only started to become available with the 1997 Hipparcos data release. Jocelyn Tomkin used this data to compile a list of brightest star in Earth's night sky at each period within the last or next 5 million years. Reanalysis of the Hipparcos data and new data from Gaia have rendered the list somewhat outdated. For example it doesn't include Gliese 710 which in about 1.35 million years time is expected to be close enough to have a magnitude of -2.7.