Astronomy:GJ 1252

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Short description: Red dwarf star in the constellation Telescopium
GJ 1252
Observation data
Equinox J2000.0]] (ICRS)
Constellation Telescopium[1]
Right ascension  20h 27m 42.08140s[2]
Declination −56° 27′ 25.1519″[2]
Apparent magnitude (V) 12.193[3]
Characteristics
Evolutionary stage Main sequence
Spectral type M2.5V[4]
Apparent magnitude (B) 13.655±0.029[3]
Apparent magnitude (V) 12.193±0.056[3]
Apparent magnitude (G) 11.235±0.003[2]
Apparent magnitude (J) 8.697±0.019[3]
Apparent magnitude (H) 8.161±0.034[3]
Apparent magnitude (K) 7.915±0.023[3]
Astrometry
Radial velocity (Rv)7.38±0.29[2] km/s
Proper motion (μ) RA: 424.417[2] mas/yr
Dec.: −1,230.941[2] mas/yr
Parallax (π)49.0555 ± 0.0247[2] mas
Distance66.49 ± 0.03 ly
(20.39 ± 0.01 pc)
Details[3]
Mass0.381±0.019 M
Radius0.391±0.020 R
Luminosity (bolometric)0.0196+0.0026
−0.0023
 L
Surface gravity (log g)4.49[2] cgs
Temperature3,458+140
−133
 K
Metallicity [Fe/H]0.1±0.1 dex
Age3.9±0.4[5] Gyr
Other designations
GJ 1252, L 210-70, LFT 1546, LHS 492, LTT 8083, NLTT 49258, PM J20277-5627, 2MASS J20274210-5627262[6]
Database references
SIMBADdata

GJ 1252 is a red dwarf star located 66.5 light-years (20.4 parsecs) away from the Solar System in the constellation of Telescopium. The star has about 38% the mass and 39% the radius of the Sun, and a temperature of about 3,458 K (3,185 °C; 5,765 °F). GJ 1252 is orbited by one known exoplanet.[3]

Planetary system

Artist's impression of GJ 1252 b[7]

GJ 1252 was found to have a planet, GJ 1252 b, in 2019 using transit observations from TESS.[3] It is a terrestrial planet larger than Earth, with about 1.3 times the mass and 1.18 times the radius of Earth. Orbiting its star with a very short period of just 12.4 hours, it is presumably tidally locked. Secondary eclipse observations have shown that GJ 1252 b lacks a significant atmosphere, similar to LHS 3844 b and TRAPPIST-1b, and have measured its dayside temperature at about 1,410 K (1,140 °C; 2,080 °F).[5][7]

The GJ 1252 planetary system[5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 1.32±0.28 M 0.00915±0.00015 0.51824160 84.8±3.2° 1.180±0.078 R

References

  1. "Finding the constellation which contains given sky coordinates". 2 August 2008. http://djm.cc/constellation.html. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Shporer, Avi et al. (February 2020). "GJ 1252 b: A 1.2 R⊕ Planet Transiting an M3 Dwarf at 20.4 pc". The Astrophysical Journal Letters 890 (1): L7. doi:10.3847/2041-8213/ab7020. Bibcode2020ApJ...890L...7S. 
  4. Reid, I. Neill et al. (October 1995). "The Palomar/MSU Nearby-Star Spectroscopic Survey. I. The Northern M Dwarfs -Bandstrengths and Kinematics". Astronomical Journal 110: 1838. doi:10.1086/117655. Bibcode1995AJ....110.1838R. 
  5. 5.0 5.1 5.2 Crossfield, Ian J. M. et al. (September 2022). "GJ 1252b: A Hot Terrestrial Super-Earth with No Atmosphere". The Astrophysical Journal Letters 937 (1): L17. doi:10.3847/2041-8213/ac886b. Bibcode2022ApJ...937L..17C. 
  6. "GJ 1252". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=GJ+1252. 
  7. 7.0 7.1 Gohd, Chelsea (11 October 2022). "Discovery Alert: Ultra-hot 'Super-Earth' Could Have No Atmosphere". NASA. https://exoplanets.nasa.gov/news/1713/discovery-alert-ultra-hot-super-earth-could-have-no-atmosphere/.