Discovery [1] | |
---|---|
Discovery site | Kepler Space Observatory |
Discovery date | 2015 |
Transit | |
Orbital characteristics [2] | |
0.0747+0.0013 −0.0012 AU | |
Eccentricity | 0.107+0.057 −0.059 |
10.0546535+0.0000088 −0.0000091 d | |
Inclination | 89.40°+0.34° −0.22° |
188°+32° −34° | |
Semi-amplitude | 2.27±0.28 m/s |
Star | K2-3 |
Physical characteristics [2] | |
Mean radius | 2.078+0.076 −0.067 R🜨 |
Mass | 5.11+0.65 −0.64 M🜨 |
Mean density | 3.11+0.49 −0.46 g/cm3 |
Temperature | 501.3+5.1 −5.2 K (228.2 °C; 442.7 °F, equilibrium) |
K2-3b, also known as EPIC 201367065 b, is an exoplanet orbiting the red dwarf K2-3 every 10 days. [3] [4] It is the largest and most massive planet of the K2-3 system, with about 2.1 times the radius of Earth and about 5 times the mass. [2] Its density of about 3.1 g/cm3 may indicate a composition of almost entirely water, or a hydrogen envelope comprising about 0.7% of the planet's mass. [5]
Ross 128 is a red dwarf in the equatorial zodiac constellation of Virgo, near β Virginis. The apparent magnitude of Ross 128 is 11.13, which is too faint to be seen with the unaided eye. Based upon parallax measurements, the distance of this star from Earth is 11.007 light-years, making it the twelfth closest stellar system to the Solar System. It was first cataloged in 1926 by American astronomer Frank Elmore Ross.
K2-3, also known as EPIC 201367065, is a red dwarf star with three known planets. It is on the borderline of being a late orange dwarf/K-type star, but because of its temperature, it is classified as a red dwarf.
K2-3c, also known as EPIC 201367065 c, is an exoplanet orbiting the red dwarf star K2-3 every 24 days. It is 143 light-years away. It has a density of about 3.7 g/cm3, indicating that it could be an ocean world or a mini-Neptune. It is the second-smallest planet in the system by both radius and mass, with a mass almost three times that of Earth.
K2-3d, also known as EPIC 201367065 d, is a confirmed exoplanet of probable mini-Neptune type orbiting the red dwarf star K2-3, and the outermost of three such planets discovered in the system. It is located 143 light-years away from Earth in the constellation of Leo. 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. It was the first planet in the Kepler "Second Light" mission to receive the letter "d" designation for a planet. Its discovery was announced in January 2015.
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.
HIP 41378 is a star located 346 light-years away in the constellation of Cancer. The star has an apparent magnitude of 8.92. This F-type main sequence dwarf has a mass of 1.15 M☉ and a radius of 1.25 R☉. It has a surface temperature of about 6,251 K.
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.
K2-138b is a potentially rocky Super-Earth exoplanet orbiting every 2 days around a K1V star. The planet, along with the four others in the system, was found by citizen scientists of the Exoplanet Explorers project on Zooniverse. It was the final planet found in the system and was officially announced on January 8, 2018.
K2-38b, also designated EPIC 204221263 b, is a massive rocky exoplanet closely orbiting a Sun-like star and is one of the densest planets ever found. Discovered in 2016 by Crossfield et al. and later characterized by Sinukoff et al., K2-38b is a rocky super-Earth about 55% larger than Earth but about 12 times more massive indicating a composition rich in iron and an extremely high surface gravity. The planet is within K2 Campaign 2, in the constellation Scorpius.
K2-138, also designated EPIC 245950175 or EE-1, is a large early K-type main sequence star with a system of at least 6 planets discovered by citizen scientists. Four were found in the first two days of the Exoplanet Explorers project on Zooniverse in early April 2017, while two more were revealed in further analysis. The system is about 660 light-years away in the constellation Aquarius, within K2 Campaign 12.
K2-66b is a confirmed mega-Earth orbiting the subgiant K2-66, about 520 parsecs (1,700 ly) from Earth in the direction of Aquarius. It is an extremely hot and dense planet heavier than Neptune, but with only about half its radius.