In today's world, Chi2 Orionis has gained great relevance in various aspects of daily life. Both on a personal and professional level, the presence of Chi2 Orionis has become a determining factor that shapes our decisions, opinions and behaviors. With the advancement of technology and globalization, Chi2 Orionis has managed to transcend borders and cultural barriers, becoming a topic of general interest and a meeting point for modern society. From its impact on the economy to its influence on politics and culture, Chi2 Orionis has woven a network of connections that affects all corners of the planet. In this article, we will closely explore the fundamental role that Chi2 Orionis plays in our daily lives and how it has managed to establish itself as a key element in the evolution of today's society.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Orion |
| Right ascension | 06h 03m 55.18437s[1] |
| Declination | +20° 08′ 18.4281″[1] |
| Apparent magnitude (V) | 4.63[2][3] |
| Characteristics | |
| Evolutionary stage | Blue supergiant |
| Spectral type | B2Ia[2] |
| U−B color index | −0.68[3] |
| B−V color index | +0.28[3] |
| R−I color index | +0.22[3] |
| Variable type | α Cyg[4] |
| Astrometry | |
| Radial velocity (Rv) | 16.8±0.9[5] km/s |
| Proper motion (μ) | RA: 2.679[1] mas/yr Dec.: −2.500[1] mas/yr |
| Parallax (π) | 0.7636±0.1219 mas[1] |
| Distance | approx. 4,300 ly (approx. 1,300 pc) |
| Absolute magnitude (MV) | −7.6[2] |
| Details | |
| Mass | 42.3±1.0[6] M☉ |
| Radius | 61.9[2] R☉ |
| Luminosity | 446,000[2] L☉ |
| Surface gravity (log g) | 2.35[2] cgs |
| Temperature | 19,000[2] K |
| Rotational velocity (v sin i) | 72[2] km/s |
| Age | 5±0.6[6] Myr |
| Other designations | |
| χ2 Ori, Chi2 Orionis, Chi2 Ori, 62 Orionis, 62 Ori, BD+20 1233, GC 7675, HD 41117, HIP 28716, HR 2135, PPM 95316, SAO 77911 | |
| Database references | |
| SIMBAD | data |
Chi2 Orionis (Chi2 Ori / χ2 Orionis / χ2 Ori) /kaɪ.tuːˈɒraɪ/ is a B-type blue supergiant star in the constellation of Orion. It has an apparent visual magnitude of 4.63 but being quite distant, and heavily extinguished it burns with the greatest absolute visual light magnitude among stars in Orion within the near reaches of the galaxy, 0.9 of a magnitude brighter than Rigel.[citation needed] Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. It is considered to be a member of the Gemini OB1 association.[2]
In apparent brightness it ranks, within Orion, admitting the higher published mean brightness of much more variable stars ranked above it, 35th.[citation needed]
Chi1 Orionis is an unrelated, yellow, main sequence star over two degrees away and far closer to the Sun.
χ2 Orionis has a B2 bright supergiant spectrum and is one of the standard B2 Ia stars.[7] It has been reported as having unusually narrow absorption lines and some weak emission lines and was included as one of the original Be stars.[8] It is no longer treated as a Be star since many supergiants show some emission features at high resolution and Be stars is usually defined to exclude supergiants.[9]

χ2 Orionis was listed as having likely small amplitude variability in photometry for the Third Catalogue of Stars measured in the Geneva Observatory Photometric System, specifically varying by 22 thousandths of a magnitude.[11] It was included in the General Catalogue of Variable Stars based on Hipparcos satellite photometry with a magnitude range (in the Hipparchos photometric system) of 4.68 - 4.72 and a period of 2.8 days.[12] A detailed study of the Hipparcos photometry confirmed the star as an α Cyg variable and gave the amplitude of variation as 0.057 magnitudes.[13]