DT Virginis

DT Virginis

Image of DT Virginis with the legacy surveys. The companion is the red object marked with an crosshair in the lower right.
Observation data
Epoch J2000      Equinox J2000
Constellation Virgo
Right ascension 13h 00m 46.557s[1]
Declination +12° 22′ 32.677″[1]
Apparent magnitude (V) 9.79[2]
Characteristics
Evolutionary stage Main sequence
Spectral type M0.5 + M7.0[3]
U−B color index 1.12[2]
B−V color index 1.44[2]
Astrometry
Radial velocity (Rv)−12.33±0.32[1] km/s
Proper motion (μ) RA: −628.7±0.184 mas/yr[1]
Dec.: −33.5±0.133 mas/yr[1]
Parallax (π)86.9010 ± 0.1170 mas[1]
Distance37.53 ± 0.05 ly
(11.51 ± 0.02 pc)
Orbit[4]
Period (P)13.63±0.03 yr
Semi-major axis (a)4.93±0.01 AU
Eccentricity (e)0.245±0.001
Inclination (i)130.3±0.3°
Longitude of the node (Ω)56.25±0.17°
Periastron epoch (T)2007.67±0.02
Argument of periastron (ω)
(secondary)		157.5±0.6°
Details
Primary (A)
Mass0.553±0.007[4] M☉
Radius0.473±0.021 R☉[5]
0.368±0.031[6] R☉
Luminosity0.044+0.016
−0.012[6] L☉
Temperature3,484±50[5] K
Metallicity [Fe/H]0.09±0.10[6] dex
Rotation2.89 d[7]
Rotational velocity (v sin i)9.6±0.9[8] km/s
Age400–800[3] Myr
Secondary (B)
Mass88.918+1.836
−2.844[9] MJup
C
Mass11.7+3.6
−3[10] MJup
Radius1.1±0.05[10] RJup
Luminosity2.51×10−6[10] L☉
Surface gravity (log g)4.38+0.16
−0.17[10] cgs
Temperature682+16
−17[10] K
Other designations
DT Vir, BD+13° 2618, GJ 494, HIP 63510, LHS 2665, LTT 13752, Ross 458, Wolf 462[11]
Database references
SIMBADdata
ARICNSdata

DT Virginis, also known as Ross 458, is a binary star system in the constellation of Virgo. It has an apparent visual magnitude of 9.79[2] and is located at a distance of 37.6 light-years from the Sun. Both of the stars are low-mass red dwarfs with at least one of them being a flare star. This binary system has a circumbinary sub-stellar companion.

A light curve for DT Virginis. The main plot, adapted from Shakhovskaya (1969),[12] shows the intensity of a flare relative to the star's quiescent intensity. The inset plot, adapted from Kiraga (2012),[13] shows the periodic variation.

This star was mentioned as a suspected variable by M. Petit in 1957.[14] In 1960, O. J. Eggen classified it as a member of the Hyades moving group based on the system's space motion;[15] it is now considered a likely member of the Carina Near Moving Group.[5] Two flares were reported from this star in 1969 by N. I. Shakhovskaya, confirming it as a flare star.[12] It was identified as an astrometric binary in 1994 by W. D. Heintz, who found a period of 14.5 years.[4] The pair were resolved using adaptive optics in 1999.[4] Early mass estimates placed the companion near the substellar limit, and it was initially proposed as a brown dwarf[16] but is now considered late-type red dwarf.[3]

The primary member, component A, is an M-type main-sequence star with a stellar classification of M0.5.[3] It is young, magnetically very active star with a high rate of rotation[16] and strong Hα emission.[3] The star experiences star spots that cover 10–15% of the surface[2] It is smaller and less massive than the Sun. The star is radiating just 4.4%[6] of the luminosity of the Sun from its photosphere at an effective temperature of 3,484 K.[5]

  1. ^ a b c d e Cite error: The named reference Gaia DR3 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Alekseev_Bondar was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Manjavacas_et_al_2019 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Laugier_et_al_2019 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference Houdebine2010 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Khata_et_al_2020 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Küker_et_al_2018 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Fouqué_et_al_2018 was invoked but never defined (see the help page).
  9. ^ Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.
  10. ^ a b c d e Cite error: The named reference Zhang2021 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. ^ a b Cite error: The named reference Shakhovskaya1969 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Kiraga was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Petit1957 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Eggen1960 was invoked but never defined (see the help page).
  16. ^ a b Cite error: The named reference Beuzit_et_al_2004 was invoked but never defined (see the help page).