| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Vulpecula |
| Right ascension | 20h 03m 00.77266s[1] |
| Declination | +28° 18′ 24.6871″[1] |
| Apparent magnitude (V) | 7.30[2] |
| Characteristics | |
| Evolutionary stage | subgiant[3] |
| Spectral type | G5 IV[4] |
| B−V color index | 0.793±0.006[2] |
| Astrometry | |
| Radial velocity (Rv) | −50.110±0.0032[5] km/s |
| Proper motion (μ) | RA: 104.273 mas/yr[1] Dec.: −69.961 mas/yr[1] |
| Parallax (π) | 15.8973 ± 0.0159 mas[1] |
| Distance | 205.2 ± 0.2 ly (62.90 ± 0.06 pc) |
| Absolute magnitude (MV) | 3.36[2] |
| Details[6] | |
| Mass | 1.18±0.05 M☉ |
| Radius | 2.38±0.13 R☉ |
| Luminosity | 4.57+1.39 −0.77 L☉ |
| Surface gravity (log g) | 3.92±0.02 cgs |
| Temperature | 5,311±13 K |
| Metallicity [Fe/H] | –0.24±0.06 dex |
| Rotational velocity (v sin i) | 1.43±0.51 km/s |
| Age | 5.07±0.78 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| ARICNS | data |
HD 190228 is a star with an orbiting substellar companion in the northern constellation of Vulpecula. Its apparent magnitude is 7.30[2] – too faint to be seen with the naked eye – and the absolute magnitude is 3.34.[2] Based on parallax measurements, it is located at a distance of 205 light-years (63 parsecs) from the Sun.[1] The system is drifting closer with a radial velocity of −50 km/s.[5]
The spectrum of HD 190228 presents as a subgiant star with a stellar classification of G5 IV,[4] indicating it has exhausted the supply of hydrogen at its core and is evolving off the main sequence. The star is older than the Sun with an age over 5 billion years with a projected rotational velocity of 1.4 km/s. A metal-poor star, it has 18% more mass than the Sun and has grown to 2.4 times the Sun's girth. The star is radiating roughly 4.6 times the luminosity of the Sun from its photosphere at an effective temperature of 5,311 K.[6]
Gaia DR3 was invoked but never defined (see the help page).Anderson_Francis_2012 was invoked but never defined (see the help page).Chen2001 was invoked but never defined (see the help page).White_et_al_2007 was invoked but never defined (see the help page).Soubiran_et_al_2018 was invoked but never defined (see the help page).Jofré_et_al_2015 was invoked but never defined (see the help page).SIMBAD was invoked but never defined (see the help page).