An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917, but was not recognized as such. The first confirmation of detection occurred in 1992. This was followed by the confirmation of a different planet, originally detected in 1988. As of 22 June 2021, there are 4,768 confirmed exoplanets in 3,527 planetary systems, with 783 systems having more than one planet.
A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets accepted by the IAU are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars. Among astronomers who use the geophysical definition of a planet, the Moon, Io and Europa may also be considered terrestrial planets. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth, as these planets are, in terms of structure, Earth-like. These planets are located between the Sun and the asteroid belt.
HD 28185 b is an extrasolar planet approximately 128.6 light-years away from Earth in the constellation of Eridanus. The planet was discovered orbiting the Sun-like star HD 28185 in April 2001 as a part of the CORALIE survey for southern extrasolar planets, and its existence was independently confirmed by the Magellan Planet Search Survey in 2008. HD 28185 b orbits its sun in a circular orbit that is at the inner edge of its star's habitable zone.
HD 69830 d is an exoplanet likely orbiting within the habitable zone of the star HD 69830, the outermost of three such planets discovered in the system. It is located approximately 40.7 light-years (12.49 parsecs, or 3.8505×1014 km) from Earth in the constellation of Puppis. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
A super-Earth is an extrasolar planet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth's, respectively. The term "super-Earth" refers only to the mass of the planet, and so does not imply anything about the surface conditions or habitability. The alternative term "gas dwarfs" may be more accurate for those at the higher end of the mass scale, although "mini-Neptunes" is a more common term.
Exoplanetology, or exoplanetary science, is an integrated field of astronomical science dedicated to the search for and study of exoplanets. It employs an interdisciplinary approach which includes astrobiology, astrophysics, astronomy, astrochemistry, astrogeology, geochemistry, and planetary science.
Pipitea, originally named HD 221287 b, is an exoplanet that orbits Poerava, approximately 173 light years away in the constellation of Tucana. This planet has mass >3.12 MJ and orbits in a habitable zone at 1.25 AUs from the star, taking 1.25 years to orbit at 29.9 km/s around the star. Naef discovered this planet in early 2007 by using HARPS spectrograph located in Chile.
HD 10180, also designated 2MASS J01375356-6030414, is a Sun-like star in the southern constellation Hydrus that is notable for its large planetary system. Since its discovery, at least seven planets, and possibly as many as nine, have been observed orbiting it, making it potentially the largest of all known planetary systems, including the Solar System. Other stars with a large known number of planets include Kepler-90, TRAPPIST-1, Kepler-11, and 55 Cancri. The star is known to host three brown dwarfs, e, f and h, after their true masses were found.
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. However, the first scientific detection of an exoplanet began in 1988. Afterwards, the first confirmed detection came in 1992, with the discovery of several 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 22 June 2021, there are 4,768 confirmed exoplanets in 3,527 planetary systems, with 783 systems having more than one planet. This is a list of the most notable discoveries.
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-47c is an exoplanet orbiting the binary star system Kepler-47, the outermost of three such planets discovered by NASA's Kepler spacecraft. The system, also involving two other exoplanets, is located about 3,400 light-years away.
Kepler-442b is a confirmed near-Earth-sized exoplanet, likely rocky, orbiting within the habitable zone of the K-type main-sequence star Kepler-442, about 1,206 light-years, from Earth in the constellation Lyra.
Kepler-452b is a super-Earth exoplanet orbiting within the inner edge of the habitable zone of the Sun-like star Kepler-452, and is the only planet in the system discovered by Kepler. It is located about 1,402 light-years (430 pc) from Earth in the constellation of Cygnus.
Kepler-452 is a G-type main-sequence star located about 1,402 light-years away from Earth in the Cygnus constellation. Although similar in temperature to the Sun, it is 20% brighter, 3.7% more massive and 11% larger. Alongside this, the star is approximately six billion years old and possesses a high metallicity. Thus, Kepler-452 can be considered a solar twin, although it could be considered a solar analog due to its age.
HD 219134 g, also known as HR 8832 g, is an unconfirmed exoplanet orbiting around the K-type star HD 219134 in the constellation of Cassiopeia. It has a minimum mass of 11 Earth Masses, suggesting that it could be a high-mass ocean planet or a Neptune-like ice giant. Unlike HD 219134 b and HD 219134 c it was not observed by the Spitzer Space Telescope and thus its radius and density are unknown. It resides closer to the star than the inner edge of the system's (empirical) habitable zone, defined by the recent Venus limit. If it has an Earth-like composition, it would have a radius 1.9 times that of Earth. However, since it is probably an ocean planet or Mini-Neptune, it is likely larger.
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.
HIP 57274 d is an exoplanet orbiting the K-type main sequence star HIP 57274 about 84.5 light-years (26 parsecs, or nearly 8.022×1016 km) from Earth in the constellation Cetus. It orbits within the outer part of its star's habitable zone, at a distance of 1.01 AU. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
EPIC 211945201 b is a Neptune-like exoplanet that orbits an F-type star. It is also called K2-236b. Its mass is 27 Earths, it takes 19.5 days to complete one orbit of its star, and is 0.148 AU from its star. Its discovery was announced in 2018. This was the first exoplanet discovered by scientists based in India. The discoverers were Abhijit Chakraborty (PRL), Arpita Roy (Caltech), Rishikesh Sharma (PRL), Suvrath Mahadevan, Priyanka Chaturvedi, Neelam J.S.S.V Prasad (PRL), and B. G. Anandarao (PRL).
HATS-36 b is a gas giant exoplanet that orbits a F-type star. Its mass is 3.216 Jupiters, it takes 4.2 days to complete one orbit of its star, and is 0.05425 AU from it. It was discovered on June 12, 2017 and was announced in 2018. Its discoverers were 23, namely Daniel Bayliss, Joel Hartman, George Zhou, Gaspar Á. Bakos, Andrew Vanderburg, J. Bento, L. Mancini, S. Ciceri, Rafael Brahm, Andres Jordán, N. Espinoza, M. Rabus, T. G. Tan, K. Penev, W. Bhatti, M. de Val-Borro, V. Suc, Z. Csubry, Th. Henning, P. Sarkis, J. Lázár, I. Papp, P. Sári.
Kepler-1649c is an Earth-sized exoplanet, likely rocky, orbiting within the habitable zone of the red dwarf star Kepler-1649, the outermost planet of the planetary system discovered by Kepler’s space telescope. It is located about 301 light-years (92 pc) away from Earth, in the constellation of Cygnus.
