Theta Serpentis

θ Serpentis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Serpens
Right ascension 18h 56m 13.18s[1]
Declination +04° 12′ 12.9″[1]
Apparent magnitude (V) +4.03 (4.62[2] + 4.98[2] + 6.71[3])
Characteristics
Spectral type A5V[4] + A5Vn[4] + G1V[5]
Astrometry
θ¹ Ser
Parallax (π)21.09 ± 2.86 mas[6]
Distanceapprox. 150 ly
(approx. 47 pc)
θ² Ser
Parallax (π)19.25 ± 3.57 mas[6]
Distanceapprox. 170 ly
(approx. 52 pc)
θ Ser C
Parallax (π)37.73 ± 0.51 mas[6]
Distance86 ± 1 ly
(26.5 ± 0.4 pc)
Absolute magnitude (MV)+4.60[7]
Details[7]
θ Ser C
Mass1.097 M☉
Radius0.9870 R☉
Luminosity1.1817 L☉
Temperature6,067 K
Metallicity [Fe/H]−0.09 dex
Age200 Myr
Other designations
63 Serpentis, ADS 11853, CCDM 18563+0413, WDS 18562+0412
θ1 Ser: Alya, θ Ser A, HR 7141, HD 175638, SAO 124068, HIP 92946, WDS 18562+0412A
θ2 Ser: θ Ser B, HR 7142, HD 175639, SAO 124070, HIP 92951, WDS 18562+0412B
θ Ser C: HD 175726, HIP 92984, WDS 18562+0412C
Database references
SIMBADθ Ser
θ¹ Ser
θ² Ser
θ Ser C

Theta Serpentis (θ Serpentis, abbreviated Theta Ser, θ Ser) is a triple star system in the constellation of Serpens.

It consists of a binary pair designated Theta Serpentis AB and whose two components are designated Theta1 Serpentis or Theta Serpentis A (officially named Alya /ˈæliə/, the traditional name for the entire system)[8][9] and Theta2 Serpentis or Theta Serpentis B, together with a third visual companion Theta Serpentis C.[10]

Based upon parallax measurements obtained during the Hipparcos mission, θ Serpentis AB is approximately 160 light-years, and θ Serpentis C approximately 86 light-years, from the Sun.

  1. ^ a b Cite error: The named reference wds was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference hr was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference tycho2 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference abt was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference mk was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference hipparcos was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference afgk was invoked but never defined (see the help page).
  8. ^ Davis, George A. (1944). "The pronunciations, derivations, and meanings of a selected list of star names". Popular Astronomy. 52: 8–30. Bibcode:1944PA.....52....8D.
  9. ^ Cite error: The named reference IAU-LSN was invoked but never defined (see the help page).
  10. ^ "Washington Double Star Catalog". United States Naval Observatory. Archived from the original on 14 February 2011. Retrieved 6 March 2018.