UY Sextantis

UY Sextantis is a post-AGB blue-white subdwarf star, located in the constellation of Sextans. The star is classed as member of the V361 Hydrae type (or also called sdBV_r type) class of pulsators in the field of asteroseismology,^[1] although it is now generally classified as class O.^[4] No additional stellar companion has been detected in tight orbit or imaged around the subdwarf star.^[8]

UY Sextantis

A white light light curve for UY Sextantis, adapted from Billeres et al. (1997).[1] All five panels form a single 10,000 second light curve, with the top panel continued on the second panel, etc.
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Sextans
Right ascension	10h 50m 02.826s[2]
Declination	−00° 00′ 36.88″[2]
Apparent magnitude (V)	13.49[3]
Characteristics
Spectral type	sdO9VII:He6[4]
Variable type	V361 Hya[1]
Astrometry
Radial velocity (Rv)	13.6[5] km/s
Proper motion (μ)	RA: −20.528 mas/yr[2] Dec.: −38.421 mas/yr[2]
Parallax (π)	1.4559±0.0789 mas[2]
Distance	2,200 ± 100 ly (690 ± 40 pc)
Details
Mass	0.490±0.014[6] M☉
Radius	0.17±0.01[6] R☉
Luminosity	25.86+3.28 −2.61[6] L☉
Surface gravity (log g)	5.83±0.01[5] cgs
Temperature	34,850±90[5] K
Rotation	24.6±3.5 d[6]
Other designations
UY Sex, GSC 04914-00003, 2MASS J10500281-0000369, PG 1047+003[7]
Database references
SIMBAD	data

The star's variability was discovered in 1998 by D. O'Donoghue et al..^[9] It was given its variable star designation in 2000.^[10] It has an apparent magnitude of 13.5 and the brightness changes amount to less than 0.1 magnitudes,^[3] with a typical period of 142 seconds.^[1]