17 Delphini
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Delphinus |
| Right ascension | 20h 55m 36.689s |
| Declination | +13° 43′ 17.531″ |
| Apparent magnitude (V) | 5.18(5.16-5.27) |
| Characteristics | |
| Spectral type | K0 III |
| U−B color index | +0.95 |
| B−V color index | +1.13 |
| Variable type | suspected |
| Astrometry | |
| Radial velocity (Rv) | −10.2±0.9 km/s |
| Proper motion (μ) | RA: +16.457 mas/yr Dec.: −11.468 mas/yr |
| Parallax (π) | 6.3132±0.0699 mas |
| Distance | 517 ± 6 ly (158 ± 2 pc) |
| Absolute magnitude (MV) | −0.64 |
| Details | |
| Mass | 2.33 M☉ |
| Radius | 23.36 R☉ |
| Luminosity | 219 L☉ |
| Surface gravity (log g) | 2.07 cgs |
| Temperature | 4,616 K |
| Metallicity [Fe/H] | −0.19 dex |
| Rotational velocity (v sin i) | 3±1 km/s |
| Age | 832 Myr |
| Other designations | |
| 17 Del, AG+13°2209, BD+13°4572, FK5 3669, GC 29201, HD 199253, HIP 103294, HR 8011, SAO 106665 | |
| Database references | |
| SIMBAD | data |
17 Delphini is a solitary star in the equatorial constellation Delphinus. It has an absolute magnitude of −0.64 and apparent magnitude of 5.18, allowing it to be faintly seen with the naked eye. Located 517 light years away, it is approaching the Solar System with a heliocentric radial velocity of −10.2 km/s.
17 Delphini is an orange giant that is most likely on the horizontal branch (84% probability). At present it has 2.33 times the mass of the Sun, but at an age of 832 million years — has expanded to 23.36 times the radius of the Sun. It shines at 219 solar luminosities from its enlarged photosphere at an effective temperature of 4,616 K, giving it an orange glow. 17 Del has an iron abundance 64% that of the Sun and spins modestly with a projected rotational velocity of 3 km/s.
17 Del is suspected to be a variable star of unknown type ranging from 5.16 to 5.27.