  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Camelopardalis[1] |
| Right ascension | 05h 09m 36.720s[2] |
| Declination | +69° 38′ 21.85″[2] |
| Apparent magnitude (V) | 6.42±0.01[3] |
| Characteristics | |
| Evolutionary stage | Horizontal branch[4] |
| Spectral type | K1 III[5] |
| U−Bcolor index | +1.03[6] |
| B−Vcolor index | +1.11[6] |
| Astrometry | |
| Radial velocity (Rv) | −6.78±0.12[2] km/s |
| Proper motion (μ) | RA: +61.031mas/yr[2] Dec.: −62.382mas/yr[2] |
| Parallax (π) | 8.2192±0.0166 mas[2] |
| Distance | 396.8 ± 0.8 ly (121.7 ± 0.2 pc) |
| Absolute magnitude (MV) | +1.04[1] |
| Details | |
| Mass | 1.2±0.1[7] M☉ |
| Radius | 10.8±0.3[7] R☉ |
| Luminosity | 46.4±0.9[7] L☉ |
| Surface gravity (log g) | 2.10±0.15[8] cgs |
| Temperature | 4,580±70[8] K |
| Metallicity[Fe/H] | −0.15±0.04[8] dex |
| Rotational velocity (v sin i) | 1.2±2[9] km/s |
| Age | 6.4±1.5[7] Gyr |
| Other designations | |
| Mago,AG+69°241,BD+69°302,GC 6245,HD 32518,HIP 24003,HR 1636,SAO 13382[10] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 32518, also namedMago, is astar with an orbitingexoplanet in the northerncircumpolar constellationCamelopardalis. It has anapparent magnitude of 6.42,[3] placing it near the limit ofnaked eye visibility. Located 397light-years away based onparallax measurements, it is receding with a heliocentricradial velocity of−6.8 km/s.[2]
HD 32518 has astellar classification of K1 III,[5] indicating that it is an orangegiant star that hasevolved away from themain sequence. It is currently on thehorizontal branch, located at the cool end in thered clump.[4] This indicates it is generating energy byhelium fusion at thecore. It has 1.2 themass of the Sun[7] but has expanded to a radius of10.8 R☉.[7] It shines at 46.4 times theluminosity of the Sun[7] from its enlargedphotosphere at aneffective temperature of 4,731 K,[4] giving it a yellowish orange glow. HD 32518 is likely to be somewhat older than theSun with an age of 6.4billion years[7] and spins slowly with aprojected rotational velocity of1.2 km/s.[9] Studies place itsmetallicity around solar level.[4]
For the 100th anniversary of theIAU HD 32518 and the planet HD 32518b were selectedNameExoWorlds campaigns forGermany. The approved name of the star HD 32518 is Mago, named afterMago National Park inEthiopia, which is noted for itsgiraffes. The name was suggested by pupils of a physics course at the Max-Born-Gymnasium inNeckargemünd.[11][12][13]
In August 2009, a group of astrometers discovered asuper-jovian exoplanet orbiting the giant star usingDoppler spectroscopy.[8] The planetary parameters were updated in 2023.[14]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b (Neri) | ≥2.849+0.160 −0.171 MJ | 0.594 | 157.35+0.10 −0.08 | 0.028+0.034 −0.019 | — | — |
