Mu Normae
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Right ascension16h 34m 05.01936s[1]
Declination−44° 02′ 43.1206″[1]
Apparentmagnitude(V)4.91[2] (4.87 - 4.98[3])
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Norma |
| Right ascension | 16h 34m 05.01936s[1] |
| Declination | −44° 02′ 43.1206″[1] |
| Apparent magnitude (V) | 4.91[2] (4.87 - 4.98[3]) |
| Characteristics | |
| Spectral type | O9.7Iab[4] |
| Apparent magnitude (U) | 4.05[5] |
| Apparent magnitude (B) | 4.99[5] |
| Apparent magnitude (J) | 4.74[5] |
| Apparent magnitude (H) | 4.679[6] |
| Apparent magnitude (K) | 4.612[6] |
| U−B color index | −0.84[5] |
| B−V color index | +0.05[5] |
| Variable type | Suspected α Cygni[3] |
| Astrometry | |
| Radial velocity (Rv) | +6.30[7] km/s |
| Proper motion (μ) | RA: +0.865[1] mas/yr Dec.: −2.985[1] mas/yr |
| Parallax (π) | 1.0967±0.1007 mas[1] |
| Distance | 3,260 ly (1,000[8] pc) |
| Absolute magnitude (MV) | −6.45[2] |
| Details[9] | |
| Mass | 33.3[10] M☉ |
| Radius | 25[2] R☉ |
| Luminosity (bolometric) | 339,000[2] L☉ |
| Surface gravity (log g) | 2.90[2] cgs |
| Temperature | 28,000[2] K |
| Rotational velocity (v sin i) | 57[2] km/s |
| Age | 4.7[10] Myr |
| Other designations | |
| Mu Normae, HD 149038, HR 6155, HIP 81122, CD−43°10900 | |
| Database references | |
| SIMBAD | data |
μ Normae, Latinised as Mu Normae, is a blue supergiant star of spectral type O9.7 Iab, located in the constellation of Norma.
It shines as bright as 339,000 Suns and weighs 40 solar masses. It varies in visual magnitude between 4.87 and 4.98, and is suspected of being an Alpha Cygni variable, which are named after Deneb.
It is in the same direction and at the same distance as the faint open cluster NGC 6169, although it is brighter than the combined magnitude of all the other stars in the cluster. It was considered the prototype of the μ Normae class of open clusters by Collinder.[12]
