HR 4887

HR 4887

NGC 4755, with HR 4887 on the right
Credit: ESO/Y. Beletsky
Observation data
Epoch J2000      Equinox J2000
Constellation Crux
Right ascension 12h 53m 21.89463s[1]
Declination −60° 19′ 46.5630″[1]
Apparent magnitude (V) 5.77[2]
Characteristics
Spectral type B9 Ia[3]
U−B color index −0.34[4]
B−V color index +0.32[4]
Variable type α Cyg?[5]
Astrometry
Radial velocity (Rv)−19.00[6] km/s
Proper motion (μ) RA: −4.299[7] mas/yr
Dec.: −1.101[7] mas/yr
Parallax (π)0.3569 ± 0.0729 mas[7]
Distanceapprox. 9,000 ly
(approx. 2,800 pc)
Absolute magnitude (MV)−7.00[8]
Details[8]
Mass18.9 M☉
Radius69.9 R☉
Luminosity112,000 L☉
Surface gravity (log g)2.02 cgs
Temperature12,680 K
Rotational velocity (v sin i)70 km/s
Age8.1 Myr
Other designations
HR 4887, CD−59°4455, HD 111904, HIP 62894, 2MASS J12532189-6019424, NSV 6008
Database references
SIMBADdata

HR 4887 (HD 111904) is a suspected variable star in the open cluster NGC 4755, which is also known as the Kappa Crucis Cluster or Jewel Box Cluster.

  1. ^ a b Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference tycho was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference vltf was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference dachs1984 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference lefever was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Gontcharov was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference dr2 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference aidelman was invoked but never defined (see the help page).