Xi Telescopii

Xi Telescopii

A light curve for Xi Telescopii, plotted from Hipparcos data
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
Right ascension 20h 07m 23.15599s
Declination −52° 52 50.8490
Apparent magnitude (V) 4.95 (+4.89 – 4.94)
Characteristics
Evolutionary stage red giant branch
Spectral type K5 III or M1 IIab
U−B color index +1.90
B−V color index +1.61
Variable type LB:
Astrometry
Radial velocity (Rv)+36.0 km/s
Proper motion (μ) RA: −12.98 mas/yr
Dec.: +7.50 mas/yr
Parallax (π)3.02±0.35 mas
Distanceapprox. 1,100 ly
(approx. 330 pc)
Absolute magnitude (MV)−2.64
Details
Mass6.6 M
Radius134 R
Luminosity3,413 L
Surface gravity (log g)0.99 cgs
Temperature4,529 K
Other designations
ξ Tel, CPD−53°9794, FK5 755, HD 190421, HIP 99120, HR 7673, SAO 246443
Database references
SIMBADdata

Xi Telescopii, Latinized from ξ Telescopii, is a solitary star in the southern constellation of Telescopium. It is visible to the naked eye, with an apparent visual magnitude of +4.95. Based upon an annual parallax shift of 3.02 mas as measured from Earth, it is located approximately 1,100 light-years from the Sun.

This is an evolved star with a stellar classification of K5 III or M1 IIab, 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. 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. With around 56 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.