HD 179433
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  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Corona Australis |
| Right ascension | 19h 14m 39.56095s[1] |
| Declination | −45° 11′ 36.6990″[1] |
| Apparent magnitude (V) | 5.91±0.01[2] |
| Characteristics | |
| Spectral type | G8 III[3] |
| B−V color index | +0.90[4] |
| Astrometry | |
| Radial velocity (Rv) | −35.1±0.4[5] km/s |
| Proper motion (μ) | RA: +47.604[1] mas/yr Dec.: −39.804[1] mas/yr |
| Parallax (π) | 9.9058±0.0428 mas[1] |
| Distance | 329 ± 1 ly (101.0 ± 0.4 pc) |
| Absolute magnitude (MV) | +1.11[6] |
| Details[7] | |
| Mass | 2.45±0.04 M☉ |
| Radius | 8.26±0.14 R☉ |
| Luminosity | 43.3±1.0 L☉ |
| Surface gravity (log g) | 2.88±0.07 cgs |
| Temperature | 5,120±30 K |
| Metallicity [Fe/H] | −0.004±0.027 dex |
| Rotational velocity (v sin i) | 2.9±1[8] km/s |
| Age | 727±10[9] Myr |
| Other designations | |
| 49 G. Coronae Australis[10], CD−45°13054, CPD−45°9650, GC 26485, HD 179433, HIP 94556, HR 7281, SAO 229573[11] | |
| Database references | |
| SIMBAD | data |
HD 179433, also known as HR 7281 or rarely 49 G. Coronae Australis, is a solitary star located in the southern constellation Corona Australis. It is faintly visible to the naked eye as a yellow-hued point of light with an apparent magnitude of 5.91.[2] Gaia DR3 parallax measurements imply a distance of 329 light-years,[1] and it is currently drifting closer with a heliocentric radial velocity of −35.1 km/s.[5] At its current distance, HD 179433's brightness is diminished by interstellar extinction of 0.22 magnitudes[12] and it has an absolute magnitude of +1.11.[6]
HD 179433 has a stellar classification of G8 III,[3] indicating that it is an evolved red giant. It has 2.45 times the mass of the Sun[7] but at the age of 727 million years,[9] it has expanded to 8.26 times the Sun's radius.[7] It radiates 43.3 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 5,120 K.[7] HD 197433 has a near solar metallicity at [Fe/H]= −0.0004[7] and it spins modestly with a projected rotational velocity of 2.9 km/s.[8]
