![]() 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] |
Distance | 37.53 ± 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) | |
Mass | 0.553±0.007 [4] M☉ |
Radius | 0.473±0.021 R☉
[5] 0.368±0.031 [6] R☉ |
Luminosity | 0.044+0.016 −0.012 [6] L☉ |
Temperature | 3,484±50 [5] K |
Metallicity [Fe/H] | 0.09±0.10 [6] dex |
Rotation | 2.89 d [7] |
Rotational velocity (v sin i) | 9.6±0.9 [8] km/s |
Age | 400–800 [3] Myr |
Secondary (B) | |
Mass | 0.090±0.005 [4] M☉ |
Mass | 88.918+1.836 −2.844 [9] MJup |
Other designations | |
Database references | |
SIMBAD | data |
ARICNS | data |
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.
This star was mentioned as a suspected variable by M. Petit in 1957. [13] In 1960, O. J. Eggen classified it as a member of the Hyades moving group based on the system's space motion; [14] 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. [11] 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 [15] 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 [15] 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]
A distant sub-stellar companion to the binary star system was discovered in 2010 as part of a deep infrared sky survey. This is most likely a T8 spectral type brown dwarf with an estimated rotation period of 6.75±1.58 h. The object varies slightly in brightness, which may be due to patchy clouds. [3] The companion lacks a detectable oxygen in the atmosphere, implying its formation from sequestrated source or peculiar atmospheric chemistry. [16]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( years) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
C | 11.3 ± 4.5 MJ | 1,168.0 | — | — | — | — |
![]() 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] |
Distance | 37.53 ± 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) | |
Mass | 0.553±0.007 [4] M☉ |
Radius | 0.473±0.021 R☉
[5] 0.368±0.031 [6] R☉ |
Luminosity | 0.044+0.016 −0.012 [6] L☉ |
Temperature | 3,484±50 [5] K |
Metallicity [Fe/H] | 0.09±0.10 [6] dex |
Rotation | 2.89 d [7] |
Rotational velocity (v sin i) | 9.6±0.9 [8] km/s |
Age | 400–800 [3] Myr |
Secondary (B) | |
Mass | 0.090±0.005 [4] M☉ |
Mass | 88.918+1.836 −2.844 [9] MJup |
Other designations | |
Database references | |
SIMBAD | data |
ARICNS | data |
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.
This star was mentioned as a suspected variable by M. Petit in 1957. [13] In 1960, O. J. Eggen classified it as a member of the Hyades moving group based on the system's space motion; [14] 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. [11] 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 [15] 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 [15] 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]
A distant sub-stellar companion to the binary star system was discovered in 2010 as part of a deep infrared sky survey. This is most likely a T8 spectral type brown dwarf with an estimated rotation period of 6.75±1.58 h. The object varies slightly in brightness, which may be due to patchy clouds. [3] The companion lacks a detectable oxygen in the atmosphere, implying its formation from sequestrated source or peculiar atmospheric chemistry. [16]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( years) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
C | 11.3 ± 4.5 MJ | 1,168.0 | — | — | — | — |