From Handwiki - Reading time: 3 min| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h 51m 58.93159s[2] |
| Declination | −46° 51′ 42.4354″[2] |
| Apparent magnitude (V) | 8.22[3] (Max) |
| Characteristics | |
| Spectral type | A7III(m)[4] |
| Variable type | Algol[5] |
| Astrometry | |
| Radial velocity (Rv) | −5.91±0.09[6] km/s |
| Proper motion (μ) | RA: +1.814[2] mas/yr Dec.: −33.369[2] mas/yr |
| Parallax (π) | 3.5831 ± 0.0796[2] mas |
| Distance | 910 ± 20 ly (279 ± 6 pc) |
| Orbit[6] | |
| Period (P) | 1.613097 d |
| Semi-major axis (a) | ≥0.019±0.0001 astronomical unit|AU |
| Eccentricity (e) | 0.00[7] |
| Inclination (i) | 82.7±0.5[8]° |
| 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 | |
| Mass | 1.88±0.04[1] M☉ |
| Radius | 2.28±0.15[1] R☉ |
| Age | 1.1[1] Gyr |
| B | |
| Mass | 1.73±0.04[1] M☉ |
| Radius | 2.08±0.16[1] R☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
HO Telescopii is an eclipsing binary star system located in the southern constellation of Telescopium. The maximum apparent visual magnitude of 8.22[3] 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.[2] The combined stellar classification of the system is A7III(m),[4] matching an evolved A-type star[10] that is possibly metallic-lined. The system is around 1.1[1] billion years old and consists of two stars of similar mass and size.[1]
The variability of this system was discovered by W. Strohmeier, R. Knigge, and H. Ott in 1965.[11][12] It is a detached binary system with both components filling three-fourths of their respective Roche lobes.[1] Their orbital period is 1.613097[6] days with a circularized orbit,[7] and the orbital plane is inclined by 83° to the line of sight from the Earth; close to edge-on.[8] 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.[3]