HD 21749 - A new Earth

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HD 21749 (HIP 16069, 2MASS J03265922-6329569) is a red dwarf star about 0.68 the mass of the Sun in the constellation Reticulum, located about 53 ly (16 pc) from Earth.[2] On 7 January 2019, it was announced that the star has two exoplanets: a possibly rocky, hot sub-Neptune-sized exoplanet, named HD 21749b; and, a sub-Earth exoplanet, tentatively named HD 21749c.[2]These exoplanets were discovered by the Transiting Exoplanet Survey Satellite (TESS).[2]
HD 21749 is a star that is approximately 68% the mass of and 76% the radius of the Sun. It has a surface temperature of 4571 K.[1] In comparison, the Sun has a surface temperature of 5778 K.[5]

The star's apparent magnitude, or how bright it appears from Earth's perspective, is 8.143.[3]
HD 21749 – star in the constellation Reticulum
Observation data
Epoch       Equinox
ConstellationReticulum[2]
Right ascension03h 26m 59.22s[1]
Declination−63° 29′ 56.9″[1]
Apparent magnitude (V)8.143[3]
Characteristics
Spectral typeK4.5V[3]
Astrometry
Radial velocity (Rv)59.46 ± 0.12[4] km/s
Proper motion (μ)RA: 355.084[4] mas/yr
Dec.: −247.460[4] mas/yr
Parallax (Ï€)61.2455 ± 0.0264[4] mas
Distance53.25 ± 0.02 ly
(16.328 ± 0.007 pc)
Details
Mass0.68 M☉
Radius0.76 R☉
Temperature4571 K
Other designations
CD−63 110 A, CPD−63 232 A, GJ 143, HIP 16069, SAO 248808, WDS J03270-6330A, TYC 8870-01392-1 A, 2MASSJ03265922-6329569[1]
Database references
SIMBADdata
Extrasolar Planets
Encyclopaedia		21749 data

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