Seen from the earth, according to the magnitude, the second star is _ _ _ _ _ _ _ _.

First of all, the visual magnitude

Count the sun, followed by Sirius.

Not counting the sun, the second one is the old star.

Second, absolute magnitude

Visually, Betelgeuse, -6.69, ranks behind Tianjin IV (-8.73).

However, it is hard to say whether the extremely blue massive stars such as sagittal augmentation 22 (ζ Pup) are calculated according to the true brightness. In fact, many WR stars are calculated according to absolute optical magnitude, but the ultraviolet rays of these stars are quite powerful.

Sirius and its companion stars

Type B Betelgeuse in Supergiant star and witch head nebula illuminated by it.