| |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h39m 41.77938s[1] |
| Declination | −45° 16′ 42.7871″[1] |
| Apparent magnitude (V) | 6.25[2] |
| Characteristics | |
| Spectral type | F2 IV[3] or F0 III:[4] |
| B−V color index | +0.28[2] |
| Variable type | δ Scuti[5] |
| Astrometry | |
| Radial velocity (Rv) | 7.8±1.5[6] km/s |
| Proper motion (μ) | RA: −22.160 mas/yr[1] Dec.: +5.375 mas/yr[1] |
| Parallax (π) | 9.8017 ± 0.0327 mas[1] |
| Distance | 333 ± 1 ly (102.0 ± 0.3 pc) |
| Absolute magnitude (MV) | +1.01[7] |
| Details | |
| Mass | 1.68[8] M☉ |
| Radius | 3.19±0.16[9] R☉ |
| Luminosity | 26.1±0.2[1] L☉ |
| Surface gravity (log g) | 3.73±0.12[10] cgs |
| Temperature | 7,380±136[11] K |
| Metallicity [Fe/H] | +0.07±0.15[12] dex |
| Rotational velocity (v sin i) | 45±5[13] km/s |
| Age | 995+121 −120[1] Myr |
| Other designations | |
66 G. Telescopii[14], QQ Tel, CD−45°13354, CPD−45°9764, GC 27167, HD 185139, HIP 96721, HR 7461, SAO 229800[15] | |
| Database references | |
| SIMBAD | data |
QQ Telescopii, also known as HD 185139 or simply QQ Tel, is a solitary variable star located in the southern constellation Telescopium. It has an apparent magnitude of 6.25,[2] placing it near the limit for naked eye visibility, even under ideal conditions. Gaia DR3 parallax measurements imply a distance of 333 light years[1] and it is currently receding with a heliocentric radial velocityof7.8 km/s.[6] At its current distance, QQ Telescopii's brightness is diminished by two tenths of a magnitude due to interstellar dust[16] and it has an absolute magnitude of +1.01.[7]
HD 185139 was discovered to be a δ Scuti variable in 1982 by Debora W. Kurtz along with HR 151 (BG Ceti).[18] After a few years of subsequent observations, it was given the variable designation QQ Telescopii in 1985.[19] In 2002, C. Koen and colleagues attempted to identify the pulsation modes of the star.[13] The brightness of QQ Tel fluctuates by about 0.05 magnitudes in the blue passband within 1.56 hours.[5]
QQ Telescopii has a stellar classification of F2 IV,[3] indicating that it is a slightly evolved F-type subgiant. It was previously classified as kA6mF0 III[20] and A0pSr(CrSi),[21] indicating that it is either a chemically peculiar Ap starorAm star. However, Renson & Manfroid (2009) considers its chemical peculiarity to be doubtful.[22] Andersen & Nordstöm (1978) give it a class of F0 III:,[4] indicating that it is an evolved F-type giant star with uncertainty about the luminosity class. Evolutionary models place it very close to the end of its main sequence life.[1]
With 1.68 times the mass of the Sun[8] and an enlarged radius 3.19 times that of the Sun,[9] QQ Telescopii radiates 26.1 times the luminosity of the Sun[1] from its photosphere at an effective temperatureof7,380 K,[11] giving it a yellowish-white hue. It is slightly metal enriched at [Fe/H] = +0.07[12] but the value is poorly constrained. The star is estimated to be 995 million years old[1] and it spins modestly with a projected rotational velocityof45 km/s.[13]
