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Star in the constellation Orion
HD 36960
Location of HD 36960 (circled)
Observation data
Epoch
J2000.0
Equinox
J2000.0
Constellation
Orion
Right ascension
5h 35m 02.68074s
[1]
Declination
−06° 00′ 07.3036″
[1]
Apparent magnitude (V)
4.72
[2]
Characteristics
Spectral type
B0.5 V
[3]
U−B
color index
−0.98
[2]
B−V
color index
−0.22
[2]
Astrometry
Radial velocity (Rv ) +27.7 km/s
Proper motion (μ)
RA: −0.66
[1]
mas /
yr
Dec.: +0.01
[1]
mas /
yr
Parallax (π) 2.02 ± 0.31
mas
[1]
Distance approx. 1,600
ly (approx. 500
pc )
Absolute magnitude (MV ) −3.18
[4]
Details
Mass 15.66
[3]
M ☉
Radius 5.6
[4]
R ☉
Luminosity 19,952
[4]
L ☉
Surface gravity (log g ) 4.10
[4]
cgs
Temperature 29,000
[4]
K
Metallicity [Fe/H]−0.20
[5]
dex
Rotational velocity (v sin i ) 28
[4] km/s
Age 6
[4]
Myr
Other designations
HD 36960,
HR 1887,
HIP 26199, IRAS 05325-0602,
BD −06°1234,
2MASS J05350268-0600074,
CCDM J05350-0600A,
WDS J05350-0600A
Database references
SIMBAD
data
HD 36960 is the brighter member of the close pair to the right of
ι Orionis towards the bottom right of the image.
HD 36960 (HR 1887 ) is a
B-type
main-sequence star in the
constellation
Orion . At an
apparent magnitude of +4.78 it is easily visible to the naked eye in many areas, though in most urban areas it cannot be seen due to
light pollution . Although it does not have a
Bayer or
Flamsteed designation , it is brighter than over 30 Flamsteed stars in Orion, as well as being brighter than any of the stars in the nearby
Orion Nebula such as
θ1 Orionis C and
θ2 Orionis .
HD 36960 forms a close pair with the slightly fainter
HD 36959 36" away. Multiple star catalogues also list the 9th magnitude BD-06°1233 as part of the system. HD 36959 is itself a very close binary with a 9th magnitude companion.
[6] All these stars are likely members of
open cluster
NGC 1980 which includes
ι Orionis 7' away.
At over 15
solar masses , it shines with around 20,000 times the Sun's luminosity due to its high surface temperature of 29,000 K and radius over five times that of the sun. It is calculated to be around six million years old, consistent with other stars thought to be members of NGC 1980.
References
^
a
b
c
d
e Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics . 474 (2): 653–664.
arXiv :
0708.1752 .
Bibcode :
2007A&A...474..653V .
doi :
10.1051/0004-6361:20078357 .
S2CID
18759600 .
^
a
b
c Reed, B. Cameron (2003).
"Catalog of Galactic OB Stars" . The Astronomical Journal . 125 (5): 2531–2533.
Bibcode :
2003AJ....125.2531R .
doi :
10.1086/374771 .
^
a
b Hohle, M. M.; Neuhäuser, R.; Schutz, B. F. (2010). "Masses and luminosities of O- and B-type stars and red supergiants". Astronomische Nachrichten . 331 (4): 349.
arXiv :
1003.2335 .
Bibcode :
2010AN....331..349H .
doi :
10.1002/asna.200911355 .
S2CID
111387483 .
^
a
b
c
d
e
f
g Nieva, María-Fernanda; Przybilla, Norbert (2014). "Fundamental properties of nearby single early B-type stars". Astronomy & Astrophysics . 566 : A7.
arXiv :
1412.1418 .
Bibcode :
2014A&A...566A...7N .
doi :
10.1051/0004-6361/201423373 .
S2CID
119227033 .
^ Nieva, M.-F.; Przybilla, N. (2012). "Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models". Astronomy & Astrophysics . 539 : A143.
arXiv :
1203.5787 .
Bibcode :
2012A&A...539A.143N .
doi :
10.1051/0004-6361/201118158 .
S2CID
119206639 .
^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001).
"The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog" . The Astronomical Journal . 122 (6): 3466.
Bibcode :
2001AJ....122.3466M .
doi :
10.1086/323920 .