"The first confirmation of the detection occurred in 1992."
Process by which planets form from protoplanetary disks around young stars, including theories like core accretion and disk instability.
Stellar Formation: The study of how stars are formed, what factors contribute to their formation and how it affects the formation of exoplanets.
Planetary Accretion: The process of how exoplanets form, how different materials interact and accumulate to produce planets.
Disk Instabilities: An important theory of exoplanet formation that posits that gravitational instabilities in a protoplanetary disk are responsible for the formation of certain exoplanets.
Protostellar Disk Chemistry: The study of the chemical reactions occurring in the protoplanetary disk from which the exoplanets are formed.
Migration: The movement of planets, both within the protoplanetary disk and after their formation, is a vital aspect of exoplanet formation.
Planetary Atmospheres: The study of the structure and composition of the atmospheres of exoplanets, including their impact on the formation, evolution and discovery of exoplanets.
Planetary Systems: The study of the structure and composition of planetary systems, including the architecture and distribution of exoplanets.
Asteroid Belts and Planetesimals: The investigation of how planetary formation interacts with the formation of asteroids, comets and other small bodies in our solar system.
Habitable Zones: The study of habitable zones around stars, including how they are formed and how they influence the formation and evolution of exoplanets.
Comparative Planetology: The comparison of exoplanetary systems with our own Solar System to better understand the process of planetary formation and the relationship between the planet and its host star.
Core-Accretion: The most popular model of exoplanet formation, which involves the gravitational attraction of dust particles around a young star, forming a core that eventually attracts and captures gases to form a planet.
Disk Instability: This model of exoplanet formation suggests that the gravitational instability of a protoplanetary disk leads to the formation of giant planet embryos that grow rapidly by accreting gas and dust.
Pebble Accretion: In this model, rocky planetesimals grow into planets by quickly accreting pebble-sized particles that stick together through static electricity.
Gravitational Collapse: In some cases, the gravitational collapse of large masses within a protoplanetary disk can lead to the formation of gas giants, especially when there is an abundance of gas available.
Planet-Planet Scattering: This model suggests that gas giants typically form outside of the frost line and are later scattered inward by other massive planets, resulting in planetary collisions and a variety of orbit patterns.
Capture: In rare instances, exoplanets can be captured by a star's gravity and become gravitationally bound to that star, even if they did not form through core-accretion.
Stellar Flybys: Rogue planets or free-floating planets can be ejected from their home systems by the gravitational interactions with other planets or stars, resulting in them moving through the galaxy on their own.
Binary Star Planet Formation: Planets can also form around binary star systems, where the gravitational forces of two stars work together to create protoplanetary disks and planetary formation.
Unconventional Models: This model includes exotic and theoretical methods of exoplanet formation, such as planetary fission, where a planet separates into multiple smaller planets or moonlets, or the 2nd generation planet formation, where a planet forms from a debris disk around an evolving star.
"As of 1 September 2023, there are 5,506 confirmed exoplanets."
"with 878 systems having more than one planet."
"The James Webb Space Telescope (JWST) is expected to discover more exoplanets, and also much more about exoplanets, including composition, environmental conditions, and potential for life."
"Transit photometry and Doppler spectroscopy have found the most."
"85% of the exoplanets detected are inside the tidal locking zone."
"About 1 in 5 Sun-like stars have an 'Earth-sized' planet in the habitable zone."
"...it can be hypothesized that there are 11 billion potentially habitable Earth-sized planets in the Milky Way, rising to 40 billion if planets orbiting the numerous red dwarfs are included."
"The least massive exoplanet known is Draugr, which is about twice the mass of the Moon."
"The most massive exoplanet listed on the NASA Exoplanet Archive is HR 2562 b, about 30 times the mass of Jupiter."
"Known orbital times for exoplanets vary from less than an hour (for those closest to their star) to thousands of years."
"However, there is evidence that extragalactic planets, exoplanets farther away in galaxies beyond the local Milky Way galaxy, may exist."
"The nearest exoplanets are located 4.2 light-years (1.3 parsecs) from Earth and orbit Proxima Centauri, the closest star to the Sun."
"The discovery of exoplanets has intensified interest in the search for extraterrestrial life."
"There is special interest in planets that orbit in a star's habitable zone (or sometimes called 'goldilocks zone'), where it is possible for liquid water, a prerequisite for life as we know it, to exist on the surface."
"Rogue planets are those that do not orbit any star."
"The rogue planets in the Milky Way possibly number in the billions or more."
"However, the study of planetary habitability also considers a wide range of other factors in determining the suitability of a planet for hosting life."
"Transit photometry and Doppler spectroscopy have found the most."
"The first possible evidence of an exoplanet was noted in 1917, but was not recognized as such."