Is the brightest star in the night time sky truly the biggest, hottest and brightest star in the Milky Way?

A star's apparent brightness in the sky is a function of both its distance from us and its true brightness; stars farther away appear much fainter than stars closer to us.

A star's apparent magnitude, which is a logarithmic scale with a difference of 5 signifying that the star appears 100 times brighter than it actually is; in other words, a magnitude 1 star is 100 times brighter than a magnitude 6 star.

A star's absolute magnitude, or how bright it would appear if it were 10 parsecs away, is a second brightness value that astronomers use to determine how bright a star actually is.

The Sun's absolute magnitude, for example, is 4.2.

With an absolute magnitude of 1.4 and an apparent magnitude of -1.46, Sirius is the brightest star in the night sky, 25 times brighter than the Sun, and 8.6 light years away.

In contrast, the star Rigel, located 1,400 light years away and 120,000 times brighter than the Sun, has an apparent magnitude of 0.12 and an absolute magnitude of -8.1.

Thus, although Rigel is about 160 times farther away from Sirius than it is, it is nearly 4,800 times brighter.

It is not the biggest, hottest, or brightest star in the Milky Way. Sirius is the brightest star in the night sky because it is comparatively close to Earth, but it is not the biggest or hottest star in the Milky Way.