HO Telescopii

HO Telescopii

A visual band light curve for HO Telescopii, adapted from Sürgit et al. (2017)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Telescopium
Right ascension 19h 51m 58.93159s
Declination −46° 51 42.4354
Apparent magnitude (V) 8.22 (Max)
Characteristics
Spectral type A7III(m)
Variable type Algol
Astrometry
Radial velocity (Rv)−5.91±0.09 km/s
Proper motion (μ) RA: +1.814 mas/yr
Dec.: −33.369 mas/yr
Parallax (π)3.5831±0.0796 mas
Distance910 ± 20 ly
(279 ± 6 pc)
Orbit
Period (P)1.613097 d
Semi-major axis (a)≥0.019±0.0001 AU
Eccentricity (e)0.00
Inclination (i)82.7±0.5°
Periastron epoch (T)2,451,875.06581±0.00027 HJD
Semi-amplitude (K1)
(primary)
131.11±0.18 km/s
Semi-amplitude (K2)
(secondary)
142.35±0.18 km/s
Details
A
Mass1.88±0.04 M
Radius2.28±0.15 R
Age1.1 Gyr
B
Mass1.73±0.04 M
Radius2.08±0.16 R
Other designations
HO Tel, CD−47°13121, HD 187418, HIP 97756, SAO 229902
Database references
SIMBADdata

HO Telescopii is an eclipsing binary star system located in the southern constellation of Telescopium. The maximum apparent visual magnitude of 8.22 is too faint to be visible to the naked eye. The system is located at a distance of approximately 910 light years based on parallax. The combined stellar classification of the system is A7III(m), matching an evolved A-type star that is possibly metallic-lined. The system is around 1.1 billion years old and consists of two stars of similar mass and size.

The variability of this system was discovered by W. Strohmeier, R. Knigge, and H. Ott in 1965. It is a detached binary system with both components filling three-fourths of their respective Roche lobes. Their orbital period is 1.613097 days with a circularized orbit, and the orbital plane is inclined by 83° to the line of sight from the Earth; close to edge-on. As a consequence, they form an Algol-like eclipsing binary with a magnitude decrease of 0.51 during the primary eclipse and 0.45 during the secondary eclipse.