Omicron Serpentis

Omicron Serpentis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Serpens
Right ascension 17h 41m 24.87286s[1]
Declination −12° 52′ 31.1086″[1]
Apparent magnitude (V) 4.26[2]
Characteristics
Spectral type A2 Va[3]
U−B color index +0.08[2]
B−V color index +0.07[2]
Variable type δ Sct[4]
Astrometry
Radial velocity (Rv)−30.2±1.2[5] km/s
Proper motion (μ) RA: −72.90[1] mas/yr
Dec.: −55.55[1] mas/yr
Parallax (π)18.83 ± 0.25 mas[1]
Distance173 ± 2 ly
(53.1 ± 0.7 pc)
Absolute magnitude (MV)+0.760[6]
Details
Mass2.13[7] M☉
Radius2.2[8] R☉
Luminosity42.6[9] L☉
Surface gravity (log g)3.82±0.14[7] cgs
Temperature8,972±305[7] K
Rotational velocity (v sin i)112.6±1.2[10] km/s
Age518[7] Myr
Other designations
ο Ser, 56 Ser, BD−12° 4808, FK5 3405, HD 160613, HIP 86565, HR 6581, SAO 160747.[11]
Database references
SIMBADdata

Omicron Serpentis (ο Ser, ο Serpentis) is a solitary[12] star in the Serpens Cauda (tail) section of the equatorial constellation Serpens. Based upon an annual parallax shift of 18.83 mas as seen from Earth,[1] it is located around 173 light years from the Sun. The star is visible to the naked eye with a base apparent visual magnitude of +4.26.[2]

This is a white-hued A-type main sequence star with a stellar classification of A2 Va.[3] It is located on the lower instability strip[6] and is classified as a Delta Scuti type variable star. The apparent magnitude of the star varies in the range 4.26−4.27 with a period of 76 minutes, or 0.053 days.[6][13]

The star has an estimated 2.13[7] times the mass of the Sun and about 2.2[8] times the Sun's radius. It is about half a billion[7] years old and is spinning with a projected rotational velocity of 112.6 km/s.[10] Omicron Serpentis is radiating 42.6[9] times the solar luminosity from its photosphere at an effective temperature of 8,972 K.[7]

In 1909, the symbiotic nova[14] RT Serpentis appeared near Omicron, although it only reached a maximum magnitude of 10.[15]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Mermilliod1986 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Houk1988_4 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference gcvs was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference Garcia1995 was invoked but never defined (see the help page).
  7. ^ a b c d e f g Cite error: The named reference David2015 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference PasinettiFracassini2001 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Mcdonald2012 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Diaz2011 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Chang2013 was invoked but never defined (see the help page).
  14. ^ Pavlenko, E. P.; Bochkov, V. V.; Vasil'yanovskaya, O. P. (1996). "9,6-Year periodicity of symbiotic nova RT Ser (1909) during the outburst decay from 1940 to 1994". Astrophysics. 39 (1): 15–19. Bibcode:1996Ap.....39...15P. doi:10.1007/BF02044949. S2CID 120532937.
  15. ^ VSX; Osborne, W. (1 April 2014). "RT Serpentis". AAVSO Website. American Association of Variable Star Observers. Retrieved 28 May 2014.