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Double star system in the constellation Equuleus
2 Equulei is a
double star system in the
constellation of
Equuleus .
The primary component of the 2 Equulei pair is an
F-type main sequence star. As of 2015, the secondary had an
angular separation of 2.90
arc seconds along a
position angle of 213° from the primary.
[3] They form a common
proper motion pair, two stars at approximately the same distance and moving in the same direction.
[4]
Gaia EDR3 gives them parallaxes of 8.8125± 0.2471
mas and 8.5577± 0.0298 mas respectively, although they are flagged as potentially unreliable.
[6]
[7] These parallaxes correspond to a distance of around 380
ly , in contrast to the
Hipparcos distance of 260± 20 ly for the two stars as a pair.
[1]
2 Equulei has been referred to in some sources as λ (Lambda) Equulei , although it was not given that
designation by Bayer.
References
^
a
b
c 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 Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics , 501 (3): 941–947,
arXiv :
0811.3982 ,
Bibcode :
2009A&A...501..941H ,
doi :
10.1051/0004-6361/200811191 ,
S2CID
118577511 .
^
a
b Mason, B. D.; et al. (2014),
"The Washington Visual Double Star Catalog" , The Astronomical Journal , 122 (6): 3466,
Bibcode :
2001AJ....122.3466M ,
doi :
10.1086/323920 , retrieved 2015-07-22
^
a
b Abt, Helmut A. (2008).
"Visual Multiples. IX. MK Spectral Types" . The Astrophysical Journal Supplement Series . 176 (1): 216–217.
Bibcode :
2008ApJS..176..216A .
doi :
10.1086/525529 .
^
a
b
c
d
e
f Casagrande, L.; et al. (2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy & Astrophysics , 530 (A138): 21,
arXiv :
1103.4651 ,
Bibcode :
2011A&A...530A.138C ,
doi :
10.1051/0004-6361/201016276 ,
S2CID
56118016 .
^
a
b
c
d
Brown, A. G. A. ; et al. (Gaia collaboration) (2021).
"Gaia Early Data Release 3: Summary of the contents and survey properties" .
Astronomy & Astrophysics . 649 : A1.
arXiv :
2012.01533 .
Bibcode :
2021A&A...649A...1G .
doi :
10.1051/0004-6361/202039657 .
S2CID
227254300 . (Erratum:
doi :
10.1051/0004-6361/202039657e ) .
Gaia EDR3 record for this source at
VizieR .
^
a
b
c
d
Brown, A. G. A. ; et al. (Gaia collaboration) (2021).
"Gaia Early Data Release 3: Summary of the contents and survey properties" .
Astronomy & Astrophysics . 649 : A1.
arXiv :
2012.01533 .
Bibcode :
2021A&A...649A...1G .
doi :
10.1051/0004-6361/202039657 .
S2CID
227254300 . (Erratum:
doi :
10.1051/0004-6361/202039657e ) .
Gaia EDR3 record for this source at
VizieR .
^
a
b
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
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 .
^
"2 Equ -- Double or multiple star" , SIMBAD Astronomical Database ,
Centre de Données astronomiques de Strasbourg , retrieved 2017-02-17 .