Psi1 Aurigae

Psi1 Aurigae (ψ1 Aur, ψ1 Aurigae) is a star in the northern constellation of Auriga. It is faintly visible to the naked eye with an apparent visual magnitude of 4.91. Based upon a measured annual parallax shift of $2,021.5$, it is approximately 2300 pc distant from the Earth. It is receding from the Sun with a radial velocity of +4.7 km/s.

This is a massive supergiant star with a stellar classification of K5-M1Iab-Ib. It is a slow irregular variable of the LC type, with its brightness varying in magnitude by 0.44. The star is more than 14 times as massive as the Sun, over 900 times larger, and is blazing with 170,000 times the Sun's luminosity. This energy is being radiated into outer space from its outer atmosphere at an effective temperature of 3,790 K, giving it the orange-red hue of a cool M-type star.