From Wikipedia, the free encyclopedia
Binary star in the constellation Boötes
Nu2 Boötis
ν
1 (right) and ν
2 (left) Boötis in optical light
Observation data
Epoch
J2000.0
Equinox
J2000.0 (
ICRS )
Constellation
Boötes
Right ascension
15h 31m 46.98170s
[1]
Declination
+40° 53′ 57.5405″
[1]
Apparent magnitude (V)
5.02
[2] (5.80 + 5.80)
[3]
Characteristics
Spectral type
A5 V
[4]
U−B
color index
+0.11
[2]
B−V
color index
+0.07
[2]
R−I
color index
0.04
Astrometry
Radial velocity (Rv ) −16.6± 3.7
[5] km/s
Proper motion (μ)
RA: -21.905
[1]
mas /
yr
Dec.: -7.876
[1]
mas /
yr
Parallax (π) 7.8618 ± 0.1449
mas
[1]
Distance 415 ± 8
ly (127 ± 2
pc )
Absolute magnitude (MV ) −0.59
[6]
Orbit
[7]
Period (P) 9.026± 0.017
yr
Semi-major axis (a) 0.0615± 0.0007 ″
Eccentricity (e) 0.006± 0.015
Inclination (i) 109.7± 1.2 °
Longitude of the node (Ω) 199.4± 0.9 °
Periastron
epoch (T) 2000 .75± 0.24
Argument of periastron (ω) (secondary) 293± 9 °
Details
Mass 2.84± 0.11
[8]
M ☉
Radius 6.21+1.07 −0.81
[1]
R ☉
Luminosity 135± 3
[1]
L ☉
Temperature 7894+574 −600
[1]
K
Rotational velocity (v sin i ) 217
[8] km/s
Other designations
ν2 Boo, ψ2 Her ,
53 Boötis ,
BD +41° 2611 ,
GC 20883,
HD 138629,
HIP 76041,
HR 5774,
SAO 45590,
ADS 9688,
CCDM 15318+4054 ,
WDS J15318+4054AB
[9]
Database references
SIMBAD
data Data sources:
Hipparcos Catalogue ,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)
Nu2 Boötis is a white-hued
binary star
[10] system in the northern
constellation of
Boötes . It is faintly visible to the naked eye with a combined
apparent visual magnitude of 5.02.
[2] Based upon an annual
parallax shift of 7.86
mas as seen from the Earth,
[1] it is located roughly 415
light years from the
Sun . The system is moving closer to the Sun with a
radial velocity of −16.6 km/s.
[5]
This stellar pair have a nearly circular orbit with a
period of nine years and a
semimajor axis of 0.0615
arc seconds .
[10] They are both of visual magnitude 5.80 and display a similar
spectrum , with the primary, component A, being an
A-type main sequence star with a
stellar classification of A5 V.
[4] This has been identified as an A-type
shell star , suggesting there is a circumstellar disk of gas orbiting one or both stars.
[11] There are two other stars that appear close to the pair, termed C and D, but they are physically unrelated.
[12]
Ptolemy considered Nu2 Boötis to be shared by
Hercules , and
Bayer assigned it a designation in both constellations: Nu2 Boötis (ν2 Boo) and Psi2 Herculis (ψ2 Her). When the modern constellation boundaries were fixed in 1930, the latter designation dropped from use.
[13]
References
^
a
b
c
d
e
f
g
h
i
Brown, A. G. A. ; et al. (Gaia collaboration) (August 2018).
"Gaia Data Release 2: Summary of the contents and survey properties" .
Astronomy & Astrophysics . 616 . A1.
arXiv :
1804.09365 .
Bibcode :
2018A&A...616A...1G .
doi :
10.1051/0004-6361/201833051 .
Gaia DR2 record for this source at
VizieR .
^
a
b
c
d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory , 4 (99): 99,
Bibcode :
1966CoLPL...4...99J .
^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal , 122 (6): 3466–3471,
Bibcode :
2001AJ....122.3466M ,
doi :
10.1086/323920
^
a
b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal , 74 : 375–406,
Bibcode :
1969AJ.....74..375C ,
doi :
10.1086/110819 .
^
a
b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics , 546 : 14,
arXiv :
1208.3048 ,
Bibcode :
2012A&A...546A..61D ,
doi :
10.1051/0004-6361/201219219 ,
S2CID
59451347 , A61.
^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters , 38 (5): 331,
arXiv :
1108.4971 ,
Bibcode :
2012AstL...38..331A ,
doi :
10.1134/S1063773712050015 ,
S2CID
119257644 .
^ Hartkopf, W. I.; et al. (June 30, 2006),
Sixth Catalog of Orbits of Visual Binary Stars , United States Naval Observatory, archived from
the original on 2017-08-01, retrieved 2017-09-13 .
^
a
b Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics , 537 : A120,
arXiv :
1201.2052 ,
Bibcode :
2012A&A...537A.120Z ,
doi :
10.1051/0004-6361/201117691 ,
S2CID
55586789 .
^
"nu02 Boo" .
SIMBAD .
Centre de données astronomiques de Strasbourg . Retrieved 2017-09-09 .
^
a
b Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems",
Monthly Notices of the Royal Astronomical Society , 389 (2): 869–879,
arXiv :
0806.2878 ,
Bibcode :
2008MNRAS.389..869E ,
doi :
10.1111/j.1365-2966.2008.13596.x ,
S2CID
14878976 .
^ Hauck, B.; Jaschek, C. (February 2000), "A-shell stars in the Geneva system", Astronomy and Astrophysics , 354 : 157–162,
Bibcode :
2000A&A...354..157H .
^ Hutter, D. J.; Tycner, C.; Zavala, R. T.; Benson, J. A.; Hummel, C. A.; Zirm, H. (2021).
"Surveying the Bright Stars by Optical Interferometry. III. A Magnitude-limited Multiplicity Survey of Classical Be Stars" . The Astrophysical Journal Supplement Series . 257 (2): 69.
arXiv :
2109.06839 .
Bibcode :
2021ApJS..257...69H .
doi :
10.3847/1538-4365/ac23cb .
S2CID
237503492 .
^
"Bayer's Uranometria and Bayer letters" . Archived from
the original on 2019-03-15. Retrieved 2012-05-18 .
External links
Hoffleit; et al. (1991),
"HR 5774" , Bright Star Catalogue (5th Revised ed.), retrieved 2017-09-13 .
"Nu2 Boötis" , Aladin previewer , Centre de Données astronomiques de Strasbourg, retrieved 2017-09-12 .