49 Orionis

This article is about d Orionis. Not to be confused with δ (delta) Orionis.
49 Orionis
Location of 49 Orionis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Orion
Right ascension 05h 38m 53.08332s[1]
Declination −07° 12′ 46.1667″[1]
Apparent magnitude (V) 4.80[2]
Characteristics
Evolutionary stage main sequence
Spectral type A4Vn[3]
U−B color index +0.11[2]
B−V color index +0.13[2]
Astrometry
Radial velocity (Rv)−5.30[4] km/s
Proper motion (μ) RA: −15.562[1] mas/yr
Dec.: −50.613[1] mas/yr
Parallax (π)23.1346 ± 0.2801 mas[1]
Distance141 ± 2 ly
(43.2 ± 0.5 pc)
Absolute magnitude (MV)1.52[5]
Details
Mass1.78[6] M☉
Radius2.0[7] R☉
Luminosity22[8] L☉
Surface gravity (log g)4.06[6] cgs
Temperature8,416±286[6] K
Rotational velocity (v sin i)186[8] km/s
Age284[6] Myr
Other designations
d Ori, 49 Ori, BD−07°1142, GC 7039, GJ 9187, HD 37507, HIP 26563, HR 1937, SAO 132411[9]
Database references
SIMBADdata

49 Orionis is a single[10] star in the equatorial constellation of Orion. It has the Bayer designation d Orionis, while 49 Orionis is the Flamsteed designation. This object is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.80.[2] It is located 141 light years away from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −5 km/s.[4]

49 Orionis (center)

In the past 49 Orionis was reported as a spectroscopic binary and an orbit was computed with a period of 445.74 days and an eccentricity of 0.549.[11] But it was later determined to be single.[10]

This object is an A-type main-sequence star with a stellar classification of A4Vn,[3] where the 'n' suffix indicates broadened "nebulous" lines caused by rapid rotation. It is around 284[6] million years old with a projected rotational velocity of 186 km/s.[8] This spin is giving the star an oblate shape with an equatorial bulge that is an estimated 8% larger than the polar radius.[12] The star has 1.8[6] times the mass of the Sun and double[7] the Sun's radius. It is radiating 22[8] times the Sun's luminosity from its photosphere at an effective temperature of 8,416 K.[6]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Ducati2002 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Gray1989 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference XHIP was invoked but never defined (see the help page).
  6. ^ a b c d e f g Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference AllendePrieto was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference Zorec2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference derosa2014 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Abt1965 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference belle2012 was invoked but never defined (see the help page).