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.
DH Tauri is a type M, or red dwarf star, one of the most common types of star in the Milky Way.[6] 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 MJ and 50 MJ, making it either a super-Jupiter or brown dwarf.[7][8] Other sources give a mass as high as 0.03 M☉, with a bolometric luminosity of 0.01 L☉.[9] The spectral type has been classified as M7.5[9] or M9.25.[10] 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.[11] 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).[12] It is potentially orbited by a smaller candidate companion DH Tauri Bb (possibly an exomoon) with 1 MJ, and a mass ratio with respect to the brown dwarf of one-tenth.[13]