HD 186756
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  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h 48m 55.08814s[1] |
| Declination | −52° 53′ 17.1953″[1] |
| Apparent magnitude (V) | 6.25[2] |
| Characteristics | |
| Spectral type | K1 III[3] |
| U−B color index | +1.12[2] |
| B−V color index | +1.13[2] |
| Astrometry | |
| Radial velocity (Rv) | −21.2±0.4[4] km/s |
| Proper motion (μ) | RA: +14.802 mas/yr[1] Dec.: −48.522 mas/yr[1] |
| Parallax (π) | 4.3872±0.0275 mas[1] |
| Distance | 743 ± 5 ly (228 ± 1 pc) |
| Absolute magnitude (MV) | −0.96[5] |
| Details | |
| Mass | 1.23[6] M☉ |
| Radius | 21.01±1.07[7] R☉ |
| Luminosity | 177±2[8] L☉ |
| Surface gravity (log g) | 1.83[6] cgs |
| Temperature | 4,747±122[9] K |
| Metallicity [Fe/H] | −0.13[6] dex |
| Rotational velocity (v sin i) | <1[10] km/s |
| Other designations | |
| 68 G. Telescopii[11], CD−53°8294, CPD−53°9678, FK5 3581, GC 27384, HD 186756, HIP 97491, HR 7521, SAO 246277[12] | |
| Database references | |
| SIMBAD | data |
HD 186756, also known as HR 7521 or rarely 68 G. Telescopii, is a solitary orange hued 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 743 light years;[1] it is currently approaching with a heliocentric radial velocity of −21.2 km/s.[4] At its current distance, HD 186756's brightness is diminished by 0.34 magnitudes due to extinction from interstellar dust[13] and it has an absolute magnitude of −0.96.[5]
This is an evolved red giant star with a stellar classification of K1 III. It has 123% the mass of the Sun[6] but it has expanded to 21.01 times the radius of the Sun.[7] The object radiates 177 times the luminosity of the Sun[8] from its enlarged photosphere at an effective temperature of 4,747 K.[9] HD 186756 is slightly metal deficient with an iron abundance of [Fe/H] = −0.13 (74% solar) and it spins too slowly for its projected rotational velocity to be measured accurately.[10]
