WASP-49
Star in the constellation Lepus
From Wikipedia, the free encyclopedia
WASP-49 is a binary star system about 636 light-years (195 parsecs) away in the constellation Lepus. The two stars are separated by 443 AU.[7] The primary is a G-type main-sequence star, with a surface temperature of 5,600 K (5,330 °C; 9,620 °F). WASP-49 is depleted of heavy elements relative to the Sun. It has a metallicity Fe/H index of –0.23, meaning it has 59% the iron level of the Sun.[6]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lepus[1] |
| Right ascension | 06h 04m 21.47357s[2] |
| Declination | −16° 57′ 55.1087″[2] |
| Apparent magnitude (V) | 11.35[3] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | G6V[4] |
| Astrometry | |
| Radial velocity (Rv) | 41.81±0.38[2] km/s |
| Proper motion (μ) | RA: +54.671 mas/yr[2] Dec.: −19.055 mas/yr[2] |
| Parallax (π) | 5.1315±0.0158 mas[2] |
| Distance | 636 ± 2 ly (194.9 ± 0.6 pc) |
| Details | |
| A | |
| Mass | 1.003±0.10[4] M☉ |
| Radius | 1.038±0.038[4] R☉ |
| Luminosity | 0.884[5] L☉ |
| Surface gravity (log g) | 4.5±0.1[4] cgs |
| Temperature | 5,600±150[6] K |
| Metallicity [Fe/H] | −0.230±0.070[6] dex |
| Rotational velocity (v sin i) | 0.90±0.30[6] km/s |
| Age | 11.9+0.8 −3.2[6] Gyr |
| B | |
| Mass | 0.337+0.009 −0.024[7] M☉ |
| Temperature | 3454+10 −25[7] K |
| Other designations | |
| WDS J06044-1658AB, TOI-479, TIC 306362738, WASP-49, TYC 5936-2086-1, 2MASS J06042146-1657550[8] | |
| Database references | |
| SIMBAD | A |
| B | |
| Exoplanet Archive | data |
Planetary system
In 2012, one exoplanet, designated WASP-49b, was discovered around the primary star by a team led by Monika Lendl.[9] This is a hot Jupiter with an equilibrium temperature of 1369±39 K.[9]
In 2017, WASP-49b was found to have an extensive sodium envelope.[4] A study in 2019 using data from the Hubble Space Telescope in near-UV found clear absorption features caused by metals, including magnesium and iron. The gaseous magnesium and iron is not gravitationally bound to the planet, but could be magnetically confined to it.[10][11] The sodium layer around WASP-49b could be due to a tidally-heated Io-like exomoon.[12][13] In October 2024, a 5-year study was published indicating that the sodium envelope most likely comes from a distinct body orbiting WASP-49b rather than the star or the planet, although the exact dynamics of the envelope remains to be settled.[14][15]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.399+0.029 −0.027 MJ |
0.0379+0.0010 −0.0011 |
2.7817387(56) | <0.026 | 84.89±0.19° | 1.115±0.047 RJ |