Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Cygnus [1] |
Right ascension | 19h 41m 55.76712s [2] |
Declination | +48° 31′ 27.9998″ [2] |
Apparent magnitude (V) | 14.769±0.206 [3] |
Characteristics | |
Evolutionary stage | main sequence star |
Spectral type | G4V[ citation needed ] |
Apparent magnitude (J) | 13.550±0.023 [4] |
Apparent magnitude (H) | 13.204±0.024 [4] |
Apparent magnitude (K) | 13.138±0.035 [4] |
Variable type | Planetary transit, [3] rotationally variable [4] |
Astrometry | |
Proper motion (μ) | RA: −5.092 mas/yr [2] Dec.: +5.839 mas/yr [2] |
Parallax (π) | 0.6462 ± 0.0165 mas [2] |
Distance | 5,000 ± 100 ly (1,550 ± 40 pc) |
Details [3] | |
Mass | 0.9700+0.0490 −0.0590 M☉ |
Radius | 0.9500+0.1660 −0.0790 R☉ |
Temperature | 5710.0+96.696 −111.431 K |
Metallicity [Fe/H] | −0.0100+0.1410 −0.1880 dex |
Age | 4.37+4.19 −2.59 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Kepler-1638 is a G-type main-sequence star located about 5,000 light years away in the constellation of Cygnus. [1] One known exoplanet has been found orbiting the star: Kepler-1638b. [5] [6] [7] [8] As of January 2021, Kepler-1638 is the farthest star with a known exoplanet orbiting in the habitable zone. [9]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | ~4.16 M🜨 | 0.745+0.021 −0.020 | 259.33683±0.01303 | — | 89.9954+0.0021 −0.0844 ° | 1.87+0.33 −0.22 R🜨 |
Kepler-1638 b is an exoplanet in orbit of its star, Kepler-1638, located in the constellation Cygnus. It was confirmed in 2016 as part of a study statistically validating hundreds of Kepler planets. Based on the parameters in the discovery paper, the planet is a super-Earth, with a radius of 1.87+0.33
−0.22 R🜨 , and a predicted mass of 4.16 Earths. It has an orbit of 259.337±0.013 days in its system's habitable zone and orbits 0.745 AU from its star. It is the most distant known exoplanet that is considered potentially habitable. [3] [8] [5] [6] [7]
However, these parameters were estimated before the first measurement of the host star's parallax was published as part of Gaia DR2 in 2018. The Gaia parallax suggests a distance of about 1,548 parsecs (5,050 light-years ), [2] much farther than the pre-Gaia estimate of about 764 parsecs (2,490 light-years). [10] This revised distance results in a significantly larger estimate of the radius of the star, and thus of the planet, with a 2018 study finding a planetary radius of 3.226+0.201
−0.315 R🜨 . This would make the planet an ice giant like Neptune, and thus not potentially habitable in an Earth-like sense. [11] [3]
Kepler-22 is a Sun-like star in the northern constellation of Cygnus, the swan, that is orbited by a planet found to be unequivocally within the star's habitable zone. It is located at the celestial coordinates: Right Ascension 19h 16m 52.2s, Declination +47° 53′ 3.9″. With an apparent visual magnitude of 11.7, this star is too faint to be seen with the naked eye. It can be viewed with a telescope having an aperture of at least 4 in (10 cm). The estimated distance to Kepler-22 is 644 light-years.
Kepler-42, formerly known as KOI-961, is a red dwarf located in the constellation Cygnus and approximately 131 light years from the Sun. It has three known extrasolar planets, all of which are smaller than Earth in radius, and likely also in mass.
Kepler-29 is a Sun-like star in the northern constellation of Cygnus. It is located at the celestial coordinates: Right Ascension 19h 53m 23.6020s, Declination +47° 29′ 28.436″. With an apparent visual magnitude of 15.456, this star is too faint to be seen with the naked eye. It is a solar analog, having a close mass, radius, and temperature as the Sun. Currently the age of the star has not been determined due to its 2780 light-year distance. As of 2016 no Jovian exoplanets of 0.9–1.4 MJ have been found at a distance of 5 AU.
Kepler-186 is a main-sequence M1-type dwarf star, located 178.5 parsecs away in the constellation of Cygnus. The star is slightly cooler than the sun, with roughly half its metallicity. It is known to have five planets, including the first Earth-sized world discovered in the habitable zone: Kepler-186f. The star hosts four other planets discovered so far, though they all orbit interior to the habitable zone.
Kepler-186f is an Earth-sized exoplanet orbiting within the habitable zone of the red dwarf star Kepler-186, the outermost of five such planets discovered around the star by NASA's Kepler spacecraft. It is located about 580 light-years from Earth in the constellation of Cygnus.
Gliese 754 is a dim star in the southern constellation of Telescopium. It has an apparent visual magnitude of 12.25, which requires a telescope to view. The star is located at a distance of 19.3 light-years from the Sun based on parallax, and it is drifting further away with a radial velocity of +7 km/s. It is one of the hundred closest stars to the Solar System. Calculations of its orbit around the Milky Way showed that it is eccentric, and indicate that it might be a thick disk object.
Kepler-283c is an exoplanet orbiting the K-type star Kepler-283 every 93 days in the circumstellar habitable zone, discovered by the Kepler space telescope in 2014.
Kepler-1229b is a confirmed super-Earth exoplanet, likely rocky, orbiting within the habitable zone of the red dwarf Kepler-1229, located about 870 light years from Earth in the constellation of Cygnus. It was discovered in 2016 by the Kepler space telescope. The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured.
Kepler-1625 is a 14th-magnitude solar-mass star located in the constellation of Cygnus approximately 7,200 light-years away. Its mass is within 5% of that of the Sun, but its radius is approximately 70% larger reflecting its more evolved state. A candidate gas giant exoplanet was detected by the Kepler Mission around the star in 2015, which was later validated as a real planet to >99% confidence in 2016. In 2018, the Hunt for Exomoons with Kepler project reported evidence for a Neptune-sized exomoon around this planet, based on observations from NASA’s Kepler mission and the Hubble Space Telescope. Subsequently, the evidence for and reality of this exomoon candidate has been subject to debate.
Kepler-1652b is a super-Earth exoplanet, orbiting within the habitable zone of the red dwarf Kepler-1652 about 822 light-years away in the Cygnus constellation. Discovered by NASA's Kepler spacecraft, Kepler-1652b was first announced as a candidate in 2013, but wasn't validated until four years later in 2017. It is a potential super-Earth with 160% Earth's radius. The planet orbits well within the habitable zone of its system, the region where liquid water can exist on a planet's surface. The planet is an eyeball planet candidate.
HD 179070, also known as Kepler-21, is a star with a closely orbiting exoplanet in the northern constellation of Lyra. At an apparent visual magnitude of 8.25 this was the brightest star observed by the Kepler spacecraft to host a validated planet until the discovery of an exoplanet orbiting HD 212657 in 2018. This system is located at a distance of 354 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −18.2 km/s.
K2-18, also known as EPIC 201912552, is a red dwarf star with two planetary companions located 124 light-years from Earth, in the constellation of Leo.
TOI-700 is a red dwarf 101.4 light-years away from Earth located in the Dorado constellation that hosts TOI-700 d, the first Earth-sized exoplanet in the habitable zone discovered by the Transiting Exoplanet Survey Satellite (TESS).
Kepler-1544b is a potentially habitable exoplanet announced in 2016 and located 1138 light years away, in the constellation of Cygnus.
Kepler-1649 is a red dwarf star of spectral type M5V with a radius 0.232 R☉, a mass 0.198 M☉, and a metallicity of -0.15 [Fe/H].
Kepler-445 is a red dwarf star located 401 light-years away in the constellation Cygnus. It hosts three known exoplanets, discovered by the transit method using data from the Kepler space telescope and confirmed in 2015. None of the planets orbit within the habitable zone.
Kepler-1708b is a Jupiter-sized exoplanet orbiting the Sun-like star Kepler-1708, located in the constellation of Cygnus approximately 5,600 light years away from Earth. It was first detected in 2011 by NASA's Kepler mission using the transit method, but was not identified as a candidate planet until 2019. In 2021, a candidate Neptune-sized exomoon in orbit around Kepler-1708b was found by astronomer David Kipping and colleagues in an analysis using Kepler transit data.
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.
Wolf 1069 is a red dwarf star located 31.2 light-years away from the Solar System in the constellation of Cygnus. The star has 17% the mass and 18% the radius of the Sun, a temperature of 3,158 K, and a slow rotation period of 150–170 days. It hosts one known exoplanet called Wolf 1069 b which could possibly sustain life.
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