HD 187420/187421
< HD 187420
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Telescopium |
| HD 187420 | |
| Right ascension | 19h 52m 37.72117s |
| Declination | −54° 58′ 15.6700″ |
| Apparent magnitude (V) | 5.71±0.01 |
| HD 187421 | |
| Right ascension | 19h 52m 39.13201s |
| Declination | −54° 58′ 35.1997″ |
| Apparent magnitude (V) | 6.37±0.01 |
| Characteristics | |
| HD 187420 | |
| Spectral type | G8/K0 III |
| U−B color index | +0.67 |
| B−V color index | +0.92 |
| HD 187421 | |
| Spectral type | A1/3 V |
| U−B color index | +0.13 |
| B−V color index | +0.10 |
| Astrometry | |
| HD 187420 | |
| Radial velocity (Rv) | −17.9±1.2 km/s |
| Proper motion (μ) | RA: +18.630 mas/yr Dec.: +3.076 mas/yr |
| Parallax (π) | 8.0046±0.0705 mas |
| Distance | 407 ± 4 ly (125 ± 1 pc) |
| Absolute magnitude (MV) | −0.33 |
| HD 187421 | |
| Radial velocity (Rv) | −21.5±1.9 km/s |
| Proper motion (μ) | RA: +19.549 mas/yr Dec.: +2.252 mas/yr |
| Parallax (π) | 7.8714 ± 0.037 mas |
| Distance | 414 ± 2 ly (127.0 ± 0.6 pc) |
| Absolute magnitude (MV) | +2.69 |
| Details | |
| HD 187420 | |
| Mass | 3.00±0.04 M☉ |
| Radius | 11.6±0.6 R☉ |
| Luminosity | 88.3+1.4 −1.5 L☉ |
| Surface gravity (log g) | 2.59 cgs |
| Temperature | 5,140±122 K |
| Metallicity [Fe/H] | −0.17 dex |
| Rotational velocity (v sin i) | 2.4±1.2 km/s |
| Age | 377±37 Myr |
| HD 187421 | |
| Mass | 2.31 M☉ |
| Radius | 2.72±0.14 R☉ |
| Luminosity | 37.1+2.4 −2.0 L☉ |
| Surface gravity (log g) | 3.92 cgs |
| Temperature | 9,099±309 K |
| Metallicity [Fe/H] | +0.20 dex |
| Rotational velocity (v sin i) | 170±2 km/s |
| Age | 560 Myr |
| Other designations | |
| HD 187420: 71 G. Telescopii, CD−55°8312, CPD−55°9221, GC 27482, HD 187420, HIP 97816, HR 7548, SAO 246311, CCDM J19526-5458A, WDS J19526-5458A | |
| HD 187421: 72 G. Telescopii, CD−55°8313, CPD−55°9222, GC 27483, HD 187421, HIP 97819, HR 7549, SAO 246312, CCDM J19526-5458B, WDS J19526-5458B | |
| Database references | |
| SIMBAD | HD 187420 |
| HD 187421 | |
HD 187420 (HR 7548; 71 G. Telescopii) and HD 187421 (HR 7549; 72 G. Telescopii), are the components of a binary star located in the southern constellation Telescopium. Gaia DR3 parallax measurements place the stars at a distance of 407 and 414 light years respectively. The two are separated by 23″, and they are approaching the Solar System with heliocentric radial velocities of −17.9 km/s and −21.5 km/s respectively.