11 Serpentis

This article is about A1 Serpentis. For other stars with this Bayer designation, see A Serpentis.
11 Serpentis
Observation data
Epoch J2000      Equinox J2000
Constellation Serpens
Right ascension 15h 32m 57.93765s[1]
Declination −01° 11′ 11.0412″[1]
Apparent magnitude (V) 5.497[2]
Characteristics
Evolutionary stage horizontal branch[2]
Spectral type K0 III[3]
B−V color index 1.092[2]
Astrometry
Radial velocity (Rv)−16.1±2.8[4] km/s
Proper motion (μ) RA: −17.765[1] mas/yr
Dec.: −42.217[1] mas/yr
Parallax (π)12.0563 ± 0.1290 mas[1]
Distance271 ± 3 ly
(82.9 ± 0.9 pc)
Absolute magnitude (MV)0.83[5]
Details
Mass1.27±0.35[6] M☉
Radius11[7] R☉
Luminosity50[7] L☉
Surface gravity (log g)2.48±0.11[6] cgs
Temperature4,767±92[6] K
Metallicity [Fe/H]−0.13[7] dex
Age2.75+0.88
−0.66[6] Gyr
Other designations
A1 Ser, 11 Ser, BD−00°2982, FK5 3226, GC 20896, HD 138562, HIP 76133, HR 5772, SAO 140596[8]
Database references
SIMBADdata

11 Serpentis is a single[9] star in the constellation of Serpens, located 271 light years away from the Sun. It has the Bayer designation A1 Serpentis,[10] 11 Serpentis is the Flamsteed designation. This object is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.497.[2] It is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.[4]

This is an aging giant star with a stellar classification of K0 III,[3] a star that has used up its core hydrogen and has expanded. It is a red clump giant on the horizontal branch, which indicates it is generating energy through the fusion of helium at its core.[2] 11 Serpentis is 2.75 billion years old with 1.3[6] times the mass of the Sun and has 11[7] times the Sun's radius. It is radiating 50[7] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,767 K.[6]

  1. ^ a b c d e Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Alves2000 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Houk1999 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  6. ^ a b c d e f Cite error: The named reference feuillet2016 was invoked but never defined (see the help page).
  7. ^ a b c d e Cite error: The named reference Massarotti2008 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Simbad was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Hoffleit1979 was invoked but never defined (see the help page).