Magnitude 5.13 | Constellation Centaurus | |
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People also search for Omicron2 Centauri, Xi1 Centauri | ||
Omicron1 Centauri (ο1 Cen, ο1 Centauri) is a star in the constellation Centaurus. It is approximately 6,000 light years from Earth.
ο1 Centauri is a yellow G-type supergiant or hypergiant with a mean apparent magnitude of +5.13. It is classified as a semiregular variable star and its brightness varies from magnitude +5.8 to +6.6 with a period of 200 days. Other studies have reported only small brightness variations. The spectral type is often given as G3 O-Ia indicating a highly luminous mass-losing hypergiant star. It has also be classified as F8 Ia0 and F7 Ia/ab. The size, luminosity, and distance are equally uncertain.
ο1 Cen forms a very close naked eye double star with ο2 Cen, a hotter supergiant that may be physically associated. ο1 has an 11th magnitude companion only 13.5" distant.