Theta Serpentis

From Wikipedia, the free encyclopedia
(Redirected from Theta1 Serpentis)
Jump to navigation Jump to search

Template:Short description

Template:Starbox relpos

Template:Starbox catalogue

θ Serpentis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Serpens
θ1 Ser
Right ascension Template:RA[1]
Declination Template:RA[1]
Apparent magnitude (V) +4.62[2]
θ2 Ser
Right ascension Template:RA[3]
Declination Template:DEC[3]
Apparent magnitude (V) +4.98[2]
Characteristics
θ1 Ser
Spectral type A5V[4]
θ2 Ser
Spectral type A5Vn[4]
Astrometry
θ1 Ser
Proper motion (μ) RA: +46.374 mas/yr[1]
Dec.: +31.313 mas/yr[1]
Parallax (π)24.2696±0.1753 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
θ2 Ser
Proper motion (μ) RA: +50.044 mas/yr[3]
Dec.: +28.363 mas/yr[3]
Parallax (π)24.5310±0.1083 mas[3]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Details
θ1 Ser
MassTemplate:Val[5] Template:Solar mass
RadiusTemplate:Val[5] Template:Solar radius
Luminosity24[6] Template:Solar luminosity
Surface gravity (log g)Template:Val[5] cgs
TemperatureTemplate:Val[5] K
Rotational velocity (v sin i)130[7] km/s
Age594[8] Myr
θ2 Ser
MassTemplate:Val[3] Template:Solar mass
RadiusTemplate:Val[3] Template:Solar radius
LuminosityTemplate:Val[3] Template:Solar luminosity
Surface gravity (log g)3.99[3] cgs
TemperatureTemplate:Val[3] K
Metallicity [Fe/H]{{{metal_fe2}}} dex
Rotational velocity (v sin i)220[7] km/s
Age390[8] Myr
Database references
SIMBADθ Ser
θ1 Ser
θ3 Ser

Script error: No such module "Check for unknown parameters".

Theta Serpentis (θ Serpentis, abbreviated Theta Ser, θ Ser) is a binary star in the constellation of Serpens. It is visible to the naked eye with a combined apparent magnitude of 4.0.[9] Based on parallax measurements, it lies about 130 light-years distant.[1][3]

The two components are designated Theta Serpentis A, officially named Alya Template:IPAc-en, the traditional name for the entire system)[10][11] also called Theta1 Serpentis, and B, also called Theta2 Serpentis.

Nomenclature

θ Serpentis (Latinised to Theta Serpentis) is the system's Bayer designation; θ1 and θ2 Serpentis those of the brightest two components. The designations of the two constituents as Theta Serpentis AB and C, and those of AB's components - Theta Serpentis A and B - derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU).[12]

The system bore the traditional name Alya, or Alga, from the Arabic الية ’alyah "fat tail (of a sheep)".[13] In 2016, the IAU organized a Working Group on Star Names (WGSN)[14] to catalogue and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems.[15] It approved the name Alya for the component Theta Serpentis A on 21 August 2016 and it is now so included in the List of IAU-approved Star Names.[11]

In the catalogue of stars in the Calendarium of Al Achsasi al Mouakket, this star was designated Dzaneb al Haiyet, which was translated into Latin as Cauda Serpentis, meaning 'the serpent's tail'.[16]

In Chinese, Script error: No such module "Lang". (Script error: No such module "Lang".), meaning Left Wall of Heavenly Market Enclosure, refers to an asterism which represents eleven old states in China, consisting of Theta Serpentis, Delta Herculis, Lambda Herculis, Mu Herculis, Omicron Herculis, 112 Herculis, Zeta Aquilae, Eta Serpentis, Nu Ophiuchi, Xi Serpentis and Eta Ophiuchi.[17] Consequently, the Chinese name for Theta Serpentis itself is Script error: No such module "Lang". (Script error: No such module "Lang"., Template:Langx), representing the state Xu (徐).[18][19]

Properties

Both Theta1 Serpentis and Theta2 Serpentis are A-type main sequence stars.[4] Template:As of, these two stars are 22 arcseconds apart on the sky along a position angle of 106°, values that changed little since the first observations in 1755.[20] At the system's distance, the angular separation give a projected separation of 900 astronomical units, implying an orbital period in the order of 10,000 years.[21] θ1 has an apparent magnitude of +4.62 while the slightly dimmer θ2 has a magnitude of +4.98.[2] Both stars are similar to each other in all respects, having luminosities of 24[6] and 13 times solar,[3] masses of 2.0 and 1.8 solar masses, radii of about twice solar and effective temperatures of Template:Val and Template:Val, respectively.[5][3]

The magnitude 6.71[22] star HD 175726[23] (Theta Serpentis C) is an optical companion to the pair. Template:As of, it is separated by 421" from A and 405" from B.[20] It is not gravitationally bound to the pair since its distance to Earth is 87 light-years, much closer than the AB pair. Its proper motion is also discrepant with that of Theta Serpentis.[24] It is a G-type main-sequence star[25] with about the same mass and radius as the Sun.[26]

References

Template:Reflist

External links

Template:Stars of Serpens

  1. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named DR3a
  2. ↑ a b c Cite error: Invalid <ref> tag; no text was provided for refs named hr
  3. ↑ a b c d e f g h i j k l Cite error: Invalid <ref> tag; no text was provided for refs named DR3b
  4. ↑ a b c Cite error: Invalid <ref> tag; no text was provided for refs named abt
  5. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named TESSInputCatalog
  6. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named mcdonald
  7. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named howe2009
  8. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named david2015
  9. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named havastro
  10. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Davis44
  11. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named IAU-LSN
  12. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named planetnaming
  13. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Kunitzsch
  14. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named WGSN
  15. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named TriRpt18
  16. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named knobel
  17. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named zh
  18. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named lcsd
  19. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named lcsd2
  20. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named wds
  21. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Kaler
  22. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named tycho2
  23. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named SIMBADc
  24. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named DR3c
  25. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named mk
  26. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named afgk
Retrieved from "http://debianws.lexgopc.com/wiki143/index.php?title=Theta_Serpentis&oldid=1873720"