Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Crater [1] |
Right ascension | 11h 02m 45.95462s [2] |
Declination | −16° 24′ 22.2882″ [2] |
Apparent magnitude (V) | 16.9±0.2 [3] |
Characteristics | |
Evolutionary stage | Red dwarf (main sequence) |
Spectral type | M6.1±0.7V [3] |
Astrometry | |
Proper motion (μ) | RA: -221.291 mas/yr [2] Dec.: -58.841 mas/yr [2] |
Parallax (π) | 37.5225 ± 0.0392 mas [2] |
Distance | 86.92 ± 0.09 ly (26.65 ± 0.03 pc) |
Details [3] | |
Mass | 0.139±0.005 M☉ |
Radius | 0.17±0.018 R☉ |
Temperature | 2960±55 K |
Metallicity [Fe/H] | -0.09±0.19 dex |
Age | 0.5±0.064 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
LP 791-18 (TOI-736) is a cool M dwarf star in the constellation Crater, located 26.65 parsecs (86.9 light-years ) away from Earth. [3]
The star is one of the smallest known to host exoplanets. [5] In 2019 two exoplanets in transit around it were announced by TESS, [3] and a third planet was discovered in Spitzer Space Telescope data in 2023. [5]
The innermost planet, b, is a super-Earth and the outermost planet, c, is a mini-Neptune. They were discovered together in 2019. [3] The middle planet, d, is an Earth-mass world discovered in 2023. It may potentially be tidally heated by interactions with planet c, which would lead to abundant volcanoes similar to Jupiter's moon Io. [5] As the planet d is in the inner edge of the habitable zone, liquid water could condense on the side of the planet that faces away from the host star. [6]
In 2021 planet c was suggested for atmospheric analysis by the James Webb Space Telescope. [7]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | — | 0.00978±0.00012 | 0.9479981±0.0000021 | — | 88.37+0.94 −0.95 ° | 1.212+0.059 −0.058 R🜨 |
d | 0.9+0.5 −0.4 M🜨 | 0.01992±0.00014 | 2.753436±0.000013 | 0.0015±0.00014 | 89.34±0.41° | 1.032+0.044 −0.043 R🜨 |
c | 7.1±0.7 M🜨 | 0.02961+0.00035 −0.00036 | 4.9899093+0.0000074 −0.0000072 | 0.00008±0.00004 | 89.78±0.13° | 2.438±0.096 R🜨 |
Gliese 436 is a red dwarf located 31.9 light-years away in the zodiac constellation of Leo. It has an apparent visual magnitude of 10.67, which is much too faint to be seen with the naked eye. However, it can be viewed with even a modest telescope of 2.4 in (6 cm) aperture. In 2004, the existence of an extrasolar planet, Gliese 436 b, was verified as orbiting the star. This planet was later discovered to transit its host star.
55 Cancri e is an exoplanet in the orbit of its Sun-like host star 55 Cancri A. The mass of the exoplanet is about 8.63 Earth masses and its diameter is about twice that of the Earth, thus making it the first super-Earth discovered around a main sequence star, predating Gliese 876 d by a year. It takes fewer than 18 hours to complete an orbit and is the innermost-known planet in its planetary system. 55 Cancri e was discovered on 30 August 2004. However, until the 2010 observations and recalculations, this planet had been thought to take about 2.8 days to orbit the star. In October 2012, it was announced that 55 Cancri e could be a carbon planet.
HD 147506, also known as HAT-P-2 and formally named Hunor, is a magnitude 8.7 F8 dwarf star that is somewhat larger and hotter than the Sun. The star is approximately 419 light-years from Earth and is positioned near the keystone of Hercules. It is estimated to be 2 to 3 billion years old, towards the end of its main sequence life. There is one known transiting exoplanet, and a second planet not observed to transit.
An exoplanet is a planet located outside the Solar System. The first evidence of an exoplanet was noted as early as 1917, but was not recognized as such until 2016; no planet discovery has yet come from that evidence. What turned out to be the first detection of an exoplanet was published among a list of possible candidates in 1988, though not confirmed until 2003. The first confirmed detection came in 1992, with the discovery of terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method and the radial-velocity method. As of 1 September 2023, there are 5,506 confirmed exoplanets in 4,065 planetary systems, with 878 systems having more than one planet. This is a list of the most notable discoveries.
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GJ 3470 b is an exoplanet orbiting the star GJ 3470, located in the constellation Cancer. With a mass of just under 14 Earth-masses and a radius approximately 4.3 times that of Earth's, it is likely something akin to Neptune despite the initially strong belief that the planet was not covered in clouds like the gas giants in the Solar System.
K2-33 is an extremely young pre-main-sequence star located about 456 light-years (140 pc) away from the Earth in the constellation of Scorpius. It is known to host one planet, a super-Neptune, named K2-33b. It is also notable for its young age.
LHS 1140 is a red dwarf in the constellation of Cetus. Based on stellar parallax measurement, it is 48.8 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 only about 18% the mass of the Sun and 21% of its radius. LHS 1140's rotational period is 130 days. No flares have been observed.
GJ 9827 is a star in the constellation of Pisces. It is a K-type main-sequence star with an apparent magnitude of 10.250. It is 97 light-years away, based on parallax.
K2-28 is a metal rich M4-type main sequence star. One confirmed transiting exoplanet is known to orbit this star. There is another star 5.2 arcseconds to the north–east of K2-28 however this star has a different proper motion and is therefore physically unrelated and probably a background star.
K2-18, also known as EPIC 201912552, is a red dwarf star located 124 light-years from Earth, in the constellation of Leo.
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L 98-59 is a bright M dwarf star, located in the constellation of Volans, at a distance of 10.608 parsecs, as measured by Gaia.
Kepler-167 is a K-type main-sequence star located about 1,119 light-years (343 pc) away from the Solar System in the constellation of Cygnus. The star has about 78% the mass and 75% the radius of the Sun, and a temperature of 4,884 K. It hosts a system of four known exoplanets. There is also a companion red dwarf star at a separation of about 700 AU, with an estimated orbital period of over 15,000 years.
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