Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Telescopium |
Right ascension | 19h 38m 35.816s [2] |
Declination | −46° 12′ 57.11″ [2] |
Characteristics | |
Spectral type | M4.5±0.5 [3] |
Variable type | AM Her [4] |
Astrometry | |
Radial velocity (Rv) | 110 km/s |
Proper motion (μ) | RA: +35.150 mas/yr [2] Dec.: −25.496 mas/yr [2] |
Parallax (π) | 5.3378±0.0834 mas [2] |
Distance | 611 ± 10 ly (187 ± 3 pc) |
Orbit [5] | |
Period (P) | 2.33 h |
Eccentricity (e) | 0.0 |
Details | |
White Dwarf | |
Mass | 0.71 [6] M☉ |
Temperature | 17,500 [6] K |
Other designations | |
QS Tel, EUVE J1938-46.2, RE 1938-461, AAVSO 1931-46 [7] | |
Database references | |
SIMBAD | data |
QS Telescopii is a faint, well-studied [4] binary star system in the southern constellation Telescopium. [7] It is composed of a white dwarf and main sequence donor star, locked into a close, circular orbit facing one another. Known as polars, material from the donor star does not form an accretion disk around the white dwarf, but rather streams directly onto it. [6] This is due to the presence of the white dwarf's strong magnetic field. The pair undergo frequent shifts between a high and low accretion states, and it shifts between single and double accretion poles. The main pole is partially self-eclipsing. [4]
In 1991, David A. H. Buckley et al. discovered that the object (then called RE 1938-461) is a variable star. [8] It was given its variable star designation, QS Telescopii, in 1995. [9] The pair of stars orbit each other with a period of 2.33 [5] hours in a circular orbit. The donor star is a small red dwarf with an estimated stellar classification of M4−5. [3] The white dwarf primary has 71% of the mass of the Sun and an effective temperature of 17,500 K. [6] It has a magnetic field strength of 50–80 MG. The system is a source for X-ray emission. [4]