Epoch J2000.0 Equinox J2000.0
|Right ascension||00h 44m 59.31s|
|Declination||−15° 16′ 16.7″|
|Apparent magnitude (V)||14.18|
|Evolutionary stage||Red dwarf|
|Radial velocity (Rv)||-13.23 ± 0.60 km/s|
|Proper motion (μ)|| RA: 317 mas/yr |
Dec.: -589 mas/yr
|Distance||40.67 ± 1.37 ly |
(12.47 ± 0.42 pc)
|Mass||0.146 ± 0.009 M☉|
|Radius||0.186 ± 0.013 R☉|
|Luminosity||0.002981 ± 0.00021 L☉|
|Temperature||3131 ± 100 K|
|Metallicity [Fe/H]||-0.24 ± 0.10 dex|
LHS 1140 is a red dwarf in the constellation of Cetus. Based on its stellar properties, it is thought to be about 41 light-years away from the Sun. 'LHS' refers to the Luyten Half-Second Catalogue of stars with proper motions exceeding half a second of arc annually. The star is over 5 billion years old and has 15% of the mass of the Sun. LHS 1140's rotational period is 130 days. No flares have been observed.
LHS 1140 has a rocky planet, LHS 1140 b, orbiting it. The planet is a super-Earth in a habitable zone and transits the star. This should allow its atmosphere to be studied in future: the combination of the transiting super-Earth and the relatively small and nearby host star make this system one of the most promising known for atmosphere studies, along with the TRAPPIST-1 system. The mass of LHS 1140b is 6.7 ± 1.8 times Earth's and its radius is 1.4 ± 0.1 times as large, giving it a density roughly 2.3 ± 0.6 times that of Earth or 12.5 g/cm3.
In July 2018, two new likely planet candidates were found by Fabo Feng, Mikko Tuomi, and Hugh R. A. Jones: an Earth-mass planet orbiting every 3.8 days and a Neptune-mass planet orbiting every 90 days.
(in order from star)
|d (candidate)||1.57-1.96 M⊕||0.025||3.78||0.07-0.19||~90°||—|
|b||6.65 ± 1.82 M⊕||0.0875||24.73712 ± 0.00025||<0.29||89.912 ± 0.071°||1.43 ± 0.10 R⊕|
|c (candidate)||9.64-11.11 M⊕||0.210||92-93||0-0.03||~90°||—|
The orbit of LHS 1140b is nearly circular with a radius of 0.09 AU. LHS 1140b orbits and transits the star every 24.7 days. The planet was discovered in 2017 by the MEarth Project. Radial velocities were measured by High Accuracy Radial Velocity Planet Searcher.
- Cutri, R. M.; et al. (2003). "2MASS All-Sky Catalog of Point Sources". VizieR On-line Data Catalog. 2246. Bibcode:2003yCat.2246....0C.
- Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Bonfils, Xavier; Astudillo-Defru, Nicola; Haywood, Raphaëlle D.; Berta-Thompson, Zachory K.; Newton, Elisabeth R.; Rodriguez, Joseph E.; Winters, Jennifer G.; Tan, Thiam-Guan; Almenara, Jose-Manuel; Bouchy, François; Delfosse, Xavier; Forveille, Thierry; Lovis, Christophe; Murgas, Felipe; Pepe, Francesco; Santos, Nuno C.; Udry, Stephane; Wünsche, Anaël; Esquerdo, Gilbert A.; Latham, David W.; Dressing, Courtney D. (2017). "A temperate rocky super-Earth transiting a nearby cool star". Nature. 544 (7650): 333. arXiv: . Bibcode:2017Natur.544..333D. doi:10.1038/nature22055. PMID 28426003.
- Salim, Samir; Gould, Andrew (2003). "Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog". The Astrophysical Journal. 582 (2): 1011. arXiv: . Bibcode:2003ApJ...582.1011S. doi:10.1086/344822.
- Luyten, Willem Jacob, Catalogue of stars with proper motions exceeding 0"5 annually, University of Minnesota, 1979
- Dickinson, David (19 April 2017). "Welcome to LHS 1140b: A Super-Earth in the Habitable Zone". Sky & Telescope. Retrieved 19 April 2017.
- Overbye, Dennis (19 April 2017). "A New Exoplanet May Be Most Promising Yet in Search for Life". New York Times. Retrieved 20 April 2017.