2 Equulei

Last updated
2 Equulei
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Equuleus
Right ascension 21h 02m 12.50262s [1]
Declination +07° 10′ 47.1545″ [1]
Apparent magnitude  (V)6.698 [2] (7.41 + 7.64) [3]
Characteristics
Spectral type F6V [4]
Astrometry
Radial velocity (Rv)−4.8±1.6 [5]  km/s
Absolute magnitude  (MV)2.16±0.18 [2]
A
Proper motion (μ)RA: −9.184 [6]   mas/yr
Dec.: −12.915 [6]   mas/yr
Parallax (π)8.8125 ± 0.2481  mas [6]
Distance 370 ± 10  ly
(113 ± 3  pc)
B
Proper motion (μ)RA: −4.238 [7]   mas/yr
Dec.: −17.934 [7]   mas/yr
Parallax (π)8.5577 ± 0.0298  mas [7]
Distance 381 ± 1  ly
(116.9 ± 0.4  pc)
Details
2 Equ A
Mass 1.73 [5]   M☉
Radius 3.37 [8]   R☉
Luminosity 13.087 [8]   L☉
Surface gravity (log g)4.05 [5]   cgs
Temperature 6,561±80 [5]   K
Metallicity [Fe/H]0.17 [5]   dex
Age 1.6 [5]   Gyr
2 Equ B
Radius 2.74 [9]   R☉
Luminosity10.828  L☉
Temperature 6,330 [9]   K
Other designations
λ  Equ, 2  Equulei, BD+06°4731, HD  200256, HIP  103813, LTT  16227, SAO  126482 [10]
Database references
SIMBAD data

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]

Related Research Articles

<span class="mw-page-title-main">Gliese 105</span> Triple star system in the constellation Cetus

Gliese 105 is a triple star system in the constellation of Cetus. It is located relatively near the Sun at a distance of 23.6 light-years. Despite this, even the brightest component is barely visible with the unaided eye (see Bortle scale). No planets have yet been detected around any of the stars in this system.

N Centauri is a binary star in the southern constellation of Centaurus. The brighter star is dimly visible to the naked eye with an apparent visual magnitude of 5.26, and it is approximately 304 light years away based on parallax. It has an absolute magnitude of +0.76 and is drifting further away from the Sun with a radial velocity of +27 km/s. It is a candidate member of the Sco OB2 moving group.

<span class="mw-page-title-main">R Canum Venaticorum</span> Star in the constellation Canes Venatici

R Canum Venaticorum is a Mira variable star in the constellation Canes Venatici. It ranges between magnitudes 6.5 and 12.9 over a period of approximately 329 days.

HD 225218 is a quadruple star system in the northern constellation of Andromeda. The primary component, HD 225218 A, is a giant star with a stellar classification of B9III, an apparent magnitude of 6.16, and is a candidate Lambda Boötis star. It has a fainter, magnitude 9.65 companion, HD 225218 B, at an angular separation of 5.2″ along a position angle of 171°. The primary itself has been identified as a binary star system through interferometry, with the two components separated by 0.165″. The pair, HD 225218 Aa and Ab, orbit each other with a period of about 70 years and an eccentricity of 0.515. Component B is likewise a spectroscopic binary.

HD 6114 is a visual binary star system in the northern constellation of Andromeda. With a combined apparent magnitude of 6.46, the star can only be seen with the naked eye by keen-eyed observers even on the best of nights. Based upon an annual parallax shift of 10.4 mas as seen from Earth's orbit, the system is located approximately 108 parsecs (350 ly) distant.

HD 130458 is a double star in the southern circumpolar constellation of Apus. The pair has a combined apparent magnitude of 5.8, making it faintly visible to the naked eye under ideal conditions. Parallax measurements place the system 310-24 light years away and it is receding with a heliocentric radial velocity of 31.4 km/s.

4 Camelopardalis is a probable multiple star in the northern constellation of Camelopardalis, located 177 light years away from the Sun, based upon parallax. With a combined apparent visual magnitude of 5.29, it is visible to the naked eye as a faint, white-hued star. The pair have a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.158″ per year. The system's proper motion makes it a candidate for membership in the IC 2391 supercluster. They are moving away from the Earth with a heliocentric radial velocity of 22.5 km/s.

<span class="mw-page-title-main">S Monocerotis</span> Star in the constellation Monoceros

S Monocerotis, also known as 15 Monocerotis, is a massive multiple and variable star system located in the constellation Monoceros. It is the brightest star in the Christmas Tree open cluster in the area catalogued as NGC 2264.

<span class="mw-page-title-main">1 Camelopardalis</span> Double star system in the constellation Camelopardalis

1 Camelopardalis is a double star system in the constellation Camelopardalis. Its combined apparent magnitude is 5.56 and it is approximately 800 parsecs (2,600 ly) away.

HD 189276 is a single star in the northern constellation Cygnus, positioned near the northern constellation border with Draco. It has an orange hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.98. The star is located at a distance of approximately 820 light years from the Sun based on parallax, and it has an absolute magnitude of −2.25. It is drifting further away with a radial velocity of +4 km/s. The star has a high peculiar velocity of 38.5+1.8
−2.2 km/s and thus is a probable runaway star.

<span class="mw-page-title-main">G 9-38</span> Star in the constellation Cancer

G 9-38, also known as EI Cancri and GJ 1116, is a binary star system consisting of two M-type stars. At 16.7 light-years from the Sun, the system is relatively nearby. The system has a very high stellar flare activity, with average five flares per hour.

ADS 9731 is a star system that consists of six stars, located in the constellation of Corona Borealis. Four of the stars are visually separate in the sky, forming a visual star system, which was resolved using adaptive optics in 1995. Two of these stars were themselves found to be spectroscopic binaries in 1998, resulting in a total of six known stars in the system. It is one of very few multiple star systems known to have at least six members.

<span class="mw-page-title-main">R Geminorum</span> Star in the constellation of Gemini

R Geminorum is a Mira variable and technetium star in the constellation Gemini. It is located approximately 850 parsecs (2,800 ly) away.

Gliese 693 is a red dwarf star and a flare star of spectral type M2 located in the constellation Pavo, 18.95 light-years from Earth.

<span class="mw-page-title-main">R Cancri</span> Variable star in the constellation Cancer

R Cancri is a Mira variable in the constellation Cancer. Located approximately 250 parsecs (830 ly) distant, it varies between magnitudes 6.07 and 12.3 over a period of approximately 357 days.

<span class="mw-page-title-main">1 Delphini</span> Star in the constellation Delphinus

1 Delphini is the Flamsteed designation for a close binary star in the equatorial constellation Delphinus. With a combined apparent magnitude of 6.08, it is barely visible to the naked eye, even under ideal conditions. Parallax measurements put the components at a distance 703 and 780 light years respectively. However, its approaching the Solar System with a radial velocity of 15 km/s.

HD 155448 is a quintuple star system consisting of 5 young B-type stars. With an apparent magnitude of 8.72, it is too dim to be visible with the naked eye.

HR 3831, also known as HD 83368, is a binary star system in the southern constellation of Vela at a distance of 233 light years. This object is barely visible to the naked eye as a dim, blue star with an apparent visual magnitude of 6.232. It is approaching the Earth with a heliocentric radial velocity of 4.0±0.3 km/s.

<span class="mw-page-title-main">11 Sagittae</span> Star in the constellation Sagitta

11 Sagittae is a star in the constellation Sagitta. It is a blue giant with a spectral classification of B9III and has evolved off the main sequence. The star will enter the Hertzsprung gap soon.

References

  1. 1 2 3 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.
  2. 1 2 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.
  3. 1 2 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
  4. 1 2 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 .
  5. 1 2 3 4 5 6 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.
  6. 1 2 3 4 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.
  7. 1 2 3 4 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.
  8. 1 2 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.
  9. 1 2 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.
  10. ↑ "2 Equ -- Double or multiple star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg , retrieved 2017-02-17.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.