Size comparison: Betelgeuse vs Rigel

Size comparison between two super giants, Betelgeuse and Rigel.

We notice that these two stars have a similar age. Betelgeuse is clearly bigger, but not more massive. The two objects are very far from the sun. Rigel is much less bright. Their nature is very different. Betelgeuse is richer in metal; Rigel's surface is very rich in carbon, nitrogen and oxygen. The star Rigel is expected to end up as a Type II supernova.

Object	Betelgeuse	Rigel
Type	Star, red supergiant	Star, blue supergiant
Age	8.5 million years	8 million years
Diameter	1,235,310,708 km	109,882,767 km
Mean radius	617,655,354 km	54,941,383 km
Mass	2.29 × 1031 kg	4.15 × 1031 kg
Surface temperature (average)	3,500 K 3,227 °C 5,840 °F	12,100 K 11,826 °C 21320 °F
Surface gravity	-0.001 m/s²	0.56 m/s²
Atmosphere composition	hydrogen, helium	hydrogen, helium, magnesium
Sun distance	724 light years	864.3 light years
Luminosity	5.73 × 1031 W	4.58 × 1026 W
Metallicity	0.05	-0.06
Spectral classification	M1–M2 Ia–ab	B8 Ia
Absolute magnitude	-5.85	-7.84
Right ascension	05h 55m 10.29s	05h 14m 32.27210s
Declination	+07° 24′ 25.3″	−08° 12′ 05.8981″

Note: if one of the objects is not visible, it just means that it is too tiny to be displayed compared to the other one.