DH Tauri

DH Tauri

DH Tauri and the b companion (lower left) with the Very Large Telescope Credit: ESO VLT SPHERE; Van Holstein et al.; Processing: Meli_thev
Observation data Epoch J2000.0      Equinox ICRS
Constellation	Taurus
DI Tauri
Right ascension	04h 29m 42.472s
Declination	+26° 32′ 49.13″
DH Tauri
Right ascension	04h 29m 41.553s
Declination	+26° 32′ 58.13″
Apparent magnitude (V)	13.1
Characteristics
Evolutionary stage	pre-main sequence
Spectral type	M0-M1Ve(T)
Variable type	T Tau
Astrometry
Proper motion (μ)	RA: 6.603 mas/yr Dec.: −20.871 mas/yr
Parallax (π)	7.4936±0.0255 mas
Distance	435 ± 1 ly (133.4 ± 0.5 pc)
Details
DI Tauri
Radius	1.21 R☉
Luminosity	0.357 L☉
Temperature	4,058 K
DH Tauri
Mass	0.41 M☉
Radius	1.26 R☉
Luminosity	0.22 L☉
Temperature	3,751 K
Age	3.16 Myr
Other designations
DH Tau, WDS J04297+2633B, IRAS 04267+2626, 2MASS J04294155+2632582
Database references
SIMBAD	data

DH Tauri, also known as DH Tau, is a type M star, located 140 parsecs (456.619 light years) away. It forms a binary system with DI Tauri 15″ away, and has a substellar companion, either a brown dwarf or massive exoplanet.

Characteristics

DH Tauri is a type M, or red dwarf star, one of the most common types of star in the Milky Way. It has an apparent magnitude of 13.71 and temperature of 3,751 K. DH Tauri has a mass of 0.41 M_☉ and an estimated radius of 1.26 R_☉, which is unusually large for a red dwarf.

The companion DH Tauri B or b has a mass estimated to be between eight M_J and 50 M_J, making it either a super-Jupiter or brown dwarf. Other sources give a mass as high as 0.03 M_☉, with a bolometric luminosity of 0.01 L_☉. The spectral type has been classified as M7.5 or M9.25. The companion has detected water vapor and carbon monoxide in its atmosphere and has a rotational velocity of 9.6 ± 0.7 km/s. This is between 9 and 15% of the breakup speed of DH Tau B. This low rotation is in agreement with magnetic coupling to a circumplanetary disk in the late stages of accretion, which reduces angular momentum of the companion. The companion, while its host star still having a protoplanetary disk, is still accreting material, being surrounded by a circumsubstellar disk (possibly a circumplanetary disk, depending on its formation history). It may have an orbiting candidate companion DH Tauri Bb, possibly an exomoon with 1 M_J, and a mass ratio with respect to the brown dwarf of one-tenth. However, the existence of this companion is uncertain, as its detection may be an artifact of instrumental effects.