Eta Telescopii
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h 22m 51.20608s |
| Declination | −54° 25′ 26.1456″ |
| Apparent magnitude (V) | +5.05 |
| Characteristics | |
| Spectral type | A0 Vn + M7V/M8V |
| B−V color index | +0.02 |
| Astrometry | |
| Radial velocity (Rv) | −5.6±2.8 km/s |
| Proper motion (μ) | RA: 25.824±0.073 mas/yr Dec.: −82.965±0.061 mas/yr |
| Parallax (π) | 20.6028±0.0988 mas |
| Distance | 158.3 ± 0.8 ly (48.5 ± 0.2 pc) |
| Absolute magnitude (MV) | +1.61 |
| Orbit | |
| Primary | A |
| Companion | B |
| Period (P) | ~1,100 years |
| Semi-major axis (a) | 142+18 −11 AU |
| Eccentricity (e) | 0.5±0.1 |
| Inclination (i) | 79°+5° −6°° |
| Details | |
| A | |
| Mass | 2.09 M☉ |
| Radius | 1.61 R☉ |
| Luminosity | 24 L☉ |
| Surface gravity (log g) | 4.60 cgs |
| Temperature | 11,941±406 K |
| Rotational velocity (v sin i) | 330 km/s |
| Age | 12 Myr |
| B | |
| Mass | 35+7 −8 MJup |
| Radius | 2.28±0.03 RJup |
| Luminosity | 3.311+0.077 −0.075×10−3 L☉ |
| Surface gravity (log g) | 4.3+0.1 −0.2 cgs |
| Temperature | 2,830+20 −30 K |
| Age | ~1–~2 Myr |
| Other designations | |
| η Tel, CPD−54°9339, HD 181296, HIP 95261, HR 7329, SAO 246055 | |
| Database references | |
| SIMBAD | data |
Eta Telescopii (η Telescopii) is a white-hued star in the southern constellation of Telescopium. This is an A-type main sequence star with an apparent visual magnitude of +5.03. It is approximately 158 light years from Earth and is a member of the Beta Pictoris Moving Group of stars that share a common motion through space. It forms a wide binary system with the star HD 181327 and has a substellar companion orbiting around it, named Eta Telescopii B.