| Observation data EpochJ2000 EquinoxJ2000 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 42m 11.49887s[1] |
| Declination | +19° 16′ 37.2375″[1] |
| Apparent magnitude (V) | 12.143[2] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | K1V[2] or late G[3] |
| Apparent magnitude (G) | 11.926±0.003[1] |
| Apparent magnitude (J) | 10.660±0.022[2] |
| Apparent magnitude (H) | 10.242±0.019[2] |
| Apparent magnitude (K) | 10.173±0.016[2] |
| Astrometry | |
| Radial velocity (Rv) | 35.37±0.42[1] km/s |
| Proper motion (μ) | RA: -36.820mas/yr[1] Dec.: -12.384mas/yr[1] |
| Parallax (π) | 5.4387±0.0184 mas[1] |
| Distance | 600 ± 2 ly (183.9 ± 0.6 pc) |
| Details[4] | |
| Mass | 0.935±0.013 M☉ |
| Radius | 0.827±0.012 R☉ |
| Surface gravity (log g) | 4.51±0.05 cgs |
| Temperature | 5300±30 K |
| Metallicity [Fe/H] | 0.18±0.02 dex |
| Rotation | 7.97 days[5] |
| Rotational velocity (v sin i) | 5.1±0.3 km/s |
| Age | 578±12 or790±30 Myr |
| Other designations | |
| Pr0211,EPIC 211936827,TIC 175291727,2MASS J08421149+1916373,NGC 2632 JC 278[2] | |
| Database references | |
| SIMBAD | data |
Pr0211 (sometimes writtenPr 0211, also 2MASS J08421149+1916373) is aSun-likelate G orearly K-type main-sequence star in theBeehive Cluster, or Praesepe, located 600light-years away in the constellationCancer. It is rotationally variable and has a rotation period of 7.97 days,[5] with its spin axis at an inclination of76°±11° to the plane of the sky.[4] Pr0211 hosts two knownexoplanets, and was the first multi-planet system to be discovered in anopen cluster.[3][4]
Pr0211 forms abinary star system with aK-type main-sequence star known as NGC 2632 JC 280 or 2MASS J08421285+1916040.[6][7][8]
Pr0211 b is agas giant exoplanet, specifically ahot Jupiter, orbiting around Pr0211. Pr0211 b along withPr0201 b are notable for being the first exoplanets discovered in theBeehive Cluster.[9][10] Pr0211 b and Pr0201 b were discovered in 2012 bySam Quinn[9][10][3] and his colleagues while observing 53 stars in the Beehive Cluster using the 1.5metres (4.9 ft; 1.6 yd) telescope at theUniversity of Georgia in theUnited States.[9]
Pr0211 c is a gas giant exoplanet orbiting around Pr0211.[11] Pr0211 c was discovered in 2016 byLuca Malavolta[11][4] and his colleagues while observing its host star with the HARPS-N spectrograph on the 3.6metres (12 ft; 3.9 yd) Italian Telescopio Nazionale Galileo (TNG) inLa Palma, and the Tillinghast Reflector Echelle Spectrograph (TRES) mounted at the 1.5metres (4.9 ft; 1.6 yd) telescope at theUniversity of Georgia in theUnited States.
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥1.88±0.03 MJ | 0.03176±0.00015 | 2.14610±0.00003 | 0.011+0.012 −0.008 | — | — |
| c | ≥7.79±0.33 MJ | 5.5+3.0 −1.4 | 4850+4560 −1750 | 0.71±0.11 | — | — |
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