36 Ophiuchi

Last updated
36 Ophiuchi
Ophiuchus constellation map.svg
Red circle.svg
36
Location of 36 Ophiuchi in the constellation Ophiuchus

Observation data
Epoch J2000       Equinox J2000
Constellation Ophiuchus
Right ascension A: 17h 15m 20.851s
B: 17h 15m 20.978s
C: 17h 16m 13.3624s [1]
Declination A: −26° 36 09.04
B: −26° 36 10.18
C: −26° 32 46.129 [1]
Apparent magnitude  (V)5.08/5.03/6.34 [1]
Characteristics
Spectral type K2 V/K1 V/K5 V [1]
U−B color index 0.51(AB)/1.04
B−V color index 0.85(AB)/1.16
Variable type C: RS CVn
Astrometry
36 Oph A
Radial velocity (Rv)−0.6 [1]  km/s
Proper motion (μ)RA: −498.600  mas/yr [2]
Dec.: −1,149.158  mas/yr [2]
Parallax (π)168.0031 ± 0.1343  mas [2]
Distance 19.41 ± 0.02  ly
(5.952 ± 0.005  pc)
36 Oph B
Radial velocity (Rv)0.0 [1]  km/s
Proper motion (μ)RA: −465.861  mas/yr [3]
Dec.: −1,141.168  mas/yr [3]
Parallax (π)168.1303 ± 0.1081  mas [3]
Distance 19.40 ± 0.01  ly
(5.948 ± 0.004  pc)
36 Oph C
Radial velocity (Rv)−0.04±0.22 [4]  km/s
Proper motion (μ)RA: −479.573  mas/yr [4]
Dec.: −1,124.332  mas/yr [4]
Parallax (π)167.9617 ± 0.0311  mas [4]
Distance 19.418 ± 0.004  ly
(5.954 ± 0.001  pc)
Orbit [5]
Companion36 Ophiuchi B
Period (P)470.9 yr
Semi-major axis (a)13″
Eccentricity (e)0.916
Inclination (i)99.8°
Details
36 Oph A
Mass 0.75+0.02
−0.04
[6]   M
Radius 0.817±0.016 [7]   R
Luminosity 0.326±0.084 [8]   L
Temperature 5,103±29 [6]   K
Metallicity [Fe/H]−0.23 [6]   dex
Age 4.86+0.50
−0.22
[6]   Gyr
36 Oph B
Mass 0.76+0.03
−0.06
[9]   M
Radius 0.709 [9] [a]   R
Luminosity0.32 [9]   L
Surface gravity (log g)4.61 [9]   cgs
Temperature 5,171±71 [9]   K
Metallicity [Fe/H]−0.22 [9]   dex
Age 5.26+5.04
−2.94
[9]   Gyr
Other designations
36 Oph, WDS  J17153-2636
AB: GJ  663, CD−26°12026, GCTP  3908.00, HIP  84405
A: Guniibuu, HR  6402, HD  155886, LHS  437, SAO  185198
B: HR  6401, HD  155885, LHS  438, SAO  185199
C: V2215  Ophiuchi, GJ  664, CD−26°12036, HD  156026, GCTP  3913.00, LHS  439, SAO  185213, HIP  84478
Database references
SIMBAD AB
A
B
C
Exoplanet Archive A
B
C
ARICNS A
B
C

36 Ophiuchi (or Guniibuu for component A) is a triple star system 19.5 light-years from Earth in the constellation Ophiuchus.

Contents

Characteristics

The primary and secondary stars (also known as HD 155886) are nearly identical orange main-sequence dwarfs of spectral type K2/K1. This binary is unusual because its eruptions do not seem to conform to the Waldmeier effect; that is, the strongest eruptions of HD 155886 are not the ones characterized by the fast eruption onset. [10] The tertiary star is an orange main-sequence dwarf of spectral type K5.

A visual band light curve for 36 Ophiuchi C (V2215 Ophiuchi), plotted from ASAS-SN data V2215OphLightCurve.png
A visual band light curve for 36 Ophiuchi C (V2215 Ophiuchi), plotted from ASAS-SN data

Star C is separated from the A-B pair by 700 arcseconds, compared to a minimum of 4.6 arcseconds for A-B, so its effect on the movements of the A-B pair is small. A and B have active chromospheres. At present the distance between the stars forming the AB-pair is 5.1 arcseconds and the position angle is 139 degrees, while star C is 731.6 arcseconds away from the A-component and situated at a position angle of 74 degrees.

Nomenclature

In the beliefs of the Kamilaroi and Euahlayi Aboriginal peoples in New South Wales, Australia, the star is called Guniibuu that represents the robin red-breast bird (Petroica boodang). In 2016, the IAU organized a Working Group on Star Names (WGSN) [12] to catalog and standardize proper names for stars. The WGSN approved the name Guniibuu for the star A on 10 August 2018 and it is now so included in the List of IAU-approved Star Names. [13]

Hunt for substellar objects

The McDonald Observatory team has set limits to the presence of one or more planets [14] around 36 Ophiuchi A with masses between 0.13 and 5.4 Jupiter masses and average separations spanning between 0.05 and 5.2 astronomical units (AU), although beyond 1.5 AU orbits are inherently unstable around either 36 Ophiuchi A or 36 Ophiuchi B. [15]

The star C (or namely HD 156026) is among five nearby paradigms as K-type stars of a type in a 'sweet spot’ between Sun-analog stars and M stars for the likelihood of evolved life, per analysis of Giada Arney from NASA's Goddard Space Flight Center. [16]

Notes

  1. Calculated, using the Stefan-Boltzmann law and the star's effective temperature and luminosity, with respect to the solar nominal effective temperature of 5,772  K:

Related Research Articles

<span class="mw-page-title-main">Atlas (star)</span> Triple star system in the constellation Taurus

Atlas, designation 27 Tauri, is a triple star system in the constellation of Taurus. It is a member of the Pleiades, an open star cluster (M45). It is 431 light-years away, and is 3.92 degrees north of the ecliptic.

<span class="mw-page-title-main">Eta Cassiopeiae</span> Binary star system in the constellation Cassiopeia

Eta Cassiopeiae is a binary star system in the northern constellation of Cassiopeia. Its binary nature was first discovered by William Herschel in August 1779. Based upon parallax measurements, the distance to this system is 19.42 light-years from the Sun. The two components are designated Eta Cassiopeiae A and B.

<span class="mw-page-title-main">Theta Eridani</span> Star in the constellation Eridanus

Theta Eridani, Latinized from θ Eridani, is a binary system in the constellation of Eridanus with a combined apparent magnitude of 2.88. Its two components are designated θ1 Eridani, formally named Acamar, and θ2 Eridani. The system's distance from the Sun based on parallax measurements is approximately 165 light-years.

<span class="mw-page-title-main">Beta Ophiuchi</span> Orange giant star in the constellation Ophiuchus

Beta Ophiuchi or β Ophiuchi, also named Cebalrai, is a star in the equatorial constellation of Ophiuchus. The apparent visual magnitude of this star is 2.7, which is readily visible to the naked eye even from urban skies. The distance to this star can be estimated using parallax measurements, yielding a value of 83.4 light-years from the Sun.

<span class="mw-page-title-main">Merope (star)</span> B-type subgiant star in the constellation Taurus

Merope, designated 23 Tauri, is a star in the constellation of Taurus and a member of the Pleiades star cluster. It is approximately 440 light-years (135 pc) away.

<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.

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.

<span class="mw-page-title-main">Gliese 445</span> Star in the constellation Camelopardalis

Gliese 445 is an M-type main sequence star in the northern part of the constellation Camelopardalis.

<span class="mw-page-title-main">V1054 Ophiuchi</span> Star system in the constellation Ophiuchus

V1054 Ophiuchi, together with the star Gliese 643, is a nearby quintuple star system. In the constellation Ophiuchus at a distance of 21.19 light-years. It consists of five stars, all of which are red dwarfs. The alternative designation of Wolf 630 forms the namesake of a moving group of stars that share a similar motion through space.

HD 85951, formally named Felis, is a solitary orange hued star in the constellation Hydra. It has an apparent magnitude of 4.94, making it faintly visible to the naked eye under ideal conditions. Based on parallax measurements, the object is about 570 light-years away from the Sun and is receding with a heliocentric radial velocity of 50 km/s.

<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.

<span class="mw-page-title-main">HD 74423</span> Variable star in the constellation Volans

HD 74423 is a heartbeat binary star and one component pulsates on only one hemisphere. This is caused by tidal interaction with its partner. The star is located in the Volans constellation.

<span class="mw-page-title-main">BP Tauri</span> Star in the constellation Taurus

BP Tauri is a young T Tauri star in the constellation of Taurus about 416 light years away, belonging to the Taurus Molecular Cloud.

<span class="mw-page-title-main">HD 203949</span> Star in the constellation Microscopium

HD 203949 is a K-type giant star 257 light-years away in the constellation of Microscopium. Its surface temperature is 4618±113 K. It is either on the red giant branch fusing hydrogen in a shell around a helium core, or more likely a red clump star currently fusing helium in its core. HD 203949 is enriched in heavy elements relative to the Sun, with a metallicity ([Fe/H]) of 0.17±0.07 dex. As is common for red giants, HD 203949 has an enhanced concentration of sodium and aluminium compared to iron.

<span class="mw-page-title-main">CG Cygni</span> Eclipsing ternary star system in constellation Cygnus

CG Cygni is a ternary star system composed of main-sequence stars in the constellation of Cygnus about 320 light years away.

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

11 Sagittae is a blue in the constellation Sagitta with a spectral type of B9III.

HD 64307, also known as HR 3075, is a solitary, orange hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.35, allowing it to be faintly seen with the naked eye. Based on parallax measurements from the Gaia spacecraft, The object is estimated to be 690 light years distant. It appears to be receding from the Sun, having a heliocentric radial velocity of 34 km/s.

HD 193472 is a solitary star in the equatorial constellation Delphinus. It has an apparent magnitude of 5.94, making it visible with the naked eye if viewed under ideal conditions. Parallax measurements put it at a distance of 282 light years and has a radial velocity of −8 km/s, indicating that the object drifting towards the Solar System.

HD 208741, also known as HR 8380, is a yellowish-white hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.91, making it faintly visible to the naked eye. Parallax measurements place it at a distance of 211 light years, and it is currently receding with a heliocentric radial velocity of 8 km/s.

References

  1. 1 2 3 4 5 6 "SIMBAD Astronomical Database". Centre de Données astronomiques de Strasbourg . Retrieved 2013-08-23.
  2. 1 2 3 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.
  3. 1 2 3 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.
  4. 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.
  5. Tokovinin, Andrei (July 2017). "Orbit Alignment in Triple Stars". The Astrophysical Journal. 844 (2): 103. arXiv: 1706.00748 . Bibcode:2017ApJ...844..103T. doi: 10.3847/1538-4357/aa7746 . ISSN   0004-637X.
  6. 1 2 3 4 Luck, R. Earle (2017-01-01). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal. 153 (1): 21. arXiv: 1611.02897 . Bibcode:2017AJ....153...21L. doi: 10.3847/1538-3881/153/1/21 . ISSN   0004-6256. 36 Ophiuchi A's database entry at VizieR.
  7. Demory, Brice-Olivier; Ségransan, Damien; Forveille, Thierry; Queloz, Didier; Beuzit, Jean-Luc; Delfosse, Xavier; Di Folco, Emmanuel; Kervella, Pierre; Le Bouquin, Jean-Baptiste; Perrier, Christian; Benisty, Myriam; Duvert, Gilles; Hofmann, Karl-Heinz; Lopez, Bruno; Petrov, Romain (October 2009). "Mass-radius relation of low and very low-mass stars revisited with the VLTI". Astronomy and Astrophysics. 505 (1): 205–215. arXiv: 0906.0602 . Bibcode:2009A&A...505..205D. doi:10.1051/0004-6361/200911976. S2CID   14786643.
  8. Hardegree-Ullman, Kevin K.; Apai, Dániel; Bergsten, Galen J.; Pascucci, Ilaria; López-Morales, Mercedes (2023-06-01). "Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable-zone Exoplanets". The Astronomical Journal . 165 (6): 267. arXiv: 2304.12490 . Bibcode:2023AJ....165..267H. doi: 10.3847/1538-3881/acd1ec . ISSN   0004-6256. 36 Ophiuchi A's database entry at VizieR.
  9. 1 2 3 4 5 6 7 Luck, R. Earle (2018-03-01). "Abundances in the Local Region. III. Southern F, G, and K Dwarfs". The Astronomical Journal. 155 (3): 111. Bibcode:2018AJ....155..111L. doi: 10.3847/1538-3881/aaa9b5 . ISSN   0004-6256. 36 Ophiuchi B's database entry at VizieR.
  10. Garg, Suyog; Karak, Bidya Binay; Egeland, Ricky; Soon, Willie; Baliunas, Sallie (2019), "Waldmeier Effect in Stellar Cycles", The Astrophysical Journal, 886 (2): 132, arXiv: 1909.12148 , Bibcode:2019ApJ...886..132G, doi: 10.3847/1538-4357/ab4a17 , S2CID   202888617
  11. "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 6 January 2022.
  12. "IAU Working Group on Star Names (WGSN)" . Retrieved 17 September 2018.
  13. "IAU Catalog of Star Names". International Astronomical Union . Retrieved 2018-09-17.
  14. Wittenmeyer et al. (2006).
  15. Irwin et al. (1996).
  16. Bill Steigerwald (2019-03-07). ""Goldilocks" Stars May Be "Just Right" for Finding Habitable Worlds". NASA . Retrieved 2020-05-12. 'I find that certain nearby K stars like 61 Cyg A/B, Epsilon Indi, Groombridge 1618, and HD 156026 may be particularly good targets for future biosignature searches,' said Arney.

Further reading