Xi Telescopii, Latinized from ξ Telescopii, is a solitary[6] star in the southern constellation of Telescopium.[11] It is visible to the naked eye, with an apparent visual magnitude of +4.95.[3] Based upon an annual parallax shift of 3.02 mas as measured from Earth,[2] it is located approximately 1,100 light-years from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 20h 07m 23.15599s[2] |
| Declination | −52° 52′ 50.8490″[2] |
| Apparent magnitude (V) | 4.95[3] (+4.89 – 4.94)[4] |
| Characteristics | |
| Spectral type | K5 III[5] or M1 IIab[6] |
| U−B color index | +1.90[3] |
| B−V color index | +1.61[3] |
| Variable type | LB:[4] |
| Astrometry | |
| Radial velocity (Rv) | +36.0[7] km/s |
| Proper motion (μ) | RA: −12.98[2] mas/yr Dec.: +7.50[2] mas/yr |
| Parallax (π) | 3.02 ± 0.35 mas[2] |
| Distance | approx. 1,100 ly (approx. 330 pc) |
| Absolute magnitude (MV) | −2.64[8] |
| Details | |
| Radius | 56[9] R☉ |
| Luminosity | 2,973[10] L☉ |
| Temperature | 4,030[10] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved star with a stellar classification of K5 III[5] or M1 IIab,[6] indicating it is a giant or bright giant star. This is a variable star tentatively classified as a slow irregular-type variable with a brightness that varies between magnitude +4.89 and +4.94.[4] Koen and Eyer examined the Hipparcos data for this star, and found that it varied periodically, with a period of 12.36 days, and an amplitude of 0.0083 magnitudes.[12] With around 56[9] times the Sun's radius, it shines with a luminosity approximately 2,973 times that of the Sun and has a surface temperature of 4,030 K.[10]