From the total of stars known to have
exoplanets
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. A different planet, init ...
(as of ), there are a total of known multiplanetary systems,
or stars with at least two confirmed planets, beyond the
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar S ...
. This list includes systems with at least three confirmed planets, or with two confirmed planets where additional candidates have been proposed. The stars with the most confirmed planets are
Sol (the Solar System's star, also referred to as the Sun) and
Kepler-90
Kepler-90, also designated 2MASS J18574403+4918185, is an F-type star located about from Earth in the constellation of Draco (constellation), Draco. It is notable for possessing a planetary system that has the same number of observed pla ...
with 8 confirmed planets each, followed by
TRAPPIST-1 with 7 planets.
The multiplanetary systems are listed below according to the star's distance from Earth. Proxima Centauri, the closest star to the Solar System, has three planets (
b,
c and
d). The nearest system with four or more confirmed planets is
Tau Ceti
Tau Ceti, Latinized from τ Ceti, is a single star in the constellation Cetus that is spectrally similar to the Sun, although it has only about 78% of the Sun's mass. At a distance of just under from the Solar System, it is a relativ ...
, with four known. The farthest confirmed multiplanetary system is OGLE-2012-BLG-0026L, at 13,300 ly away.
The table below contains information about the coordinates, spectral and physical properties, and number of confirmed (unconfirmed) planets for systems with at list 2 planets and 1 not confirmed. The two most important
stellar properties
Pages Related to Stellar properties, Pages using the word stellar in a physics context.
* Stellar aberration
* Stellar aberration (derivation from Lorentz transformation)
* Stellar age estimation
* Stellar archaeology
* Stellar astronomy
* Stella ...
are
mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...
and
metallicity
In astronomy, metallicity is the abundance of elements present in an object that are heavier than hydrogen and helium. Most of the normal physical matter in the Universe is either hydrogen or helium, and astronomers use the word ''"metals"'' as a ...
because they determine how these
planetary system
A planetary system is a set of gravitationally
In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interacti ...
s form. Systems with higher mass and metallicity tend to have more planets and more massive planets. However, although low metallicity stars tend to have fewer massive planets, particularly hot-Jupiters, they also tend to have a larger number of close in planets, orbiting at less than 1 AU.
Multiplanetary systems
*Need to be added: EPIC 249893012
Stars orbited by both planets and brown dwarfs
Stars orbited by objects on both sides of the 13
Jupiter mass
Jupiter mass, also called Jovian mass, is the unit of mass equal to the total mass of the planet Jupiter. This value may refer to the mass of the planet alone, or the mass of the entire Jovian system to include the moons of Jupiter. Jupiter is b ...
dividing line.
*
54 Piscium
54 Piscium is an orange dwarf star approximately 36 light-years away in the constellation of Pisces (constellation), Pisces. In 2003, an extrasolar planet was confirmed to be orbiting the star, and in 2006, a brown dwarf was also discover ...
(HD 3651)
*
HD 168443
HD 168443 is an ordinary yellow-hued star in the Serpens Cauda segment of the equatorial constellation of Serpens. It is known to have two substellar companions. With an apparent visual magnitude of 6.92, the star lies just below the nomin ...
*
Gliese 229
Gliese 229 (also written as Gl 229 or GJ 229) is a binary system composed of a red dwarf and the first brown dwarf seen by astronomers, 18.8 light years away in the constellation Lepus. The primary component has 58% of the mass of the S ...
A
*
Epsilon Indi
Epsilon Indi, Latinized from ε Indi, is a star system located at a distance of approximately 12 light-years from Earth in the southern constellation of Indus. The star has an orange hue and is faintly visible to the naked eye with an a ...
*
HD 82943
HD 82943 (164 G. Hydrae) is a yellow dwarf star approximately 89 light-years away in the constellation of Hydra. Two extrasolar planets have been confirmed to be orbiting it, and it is thought that the system had more giant planets that ...
*
Pi Mensae
Pi Mensae (π Men), also known as HD 39091, is a yellow dwarf star in the constellation of Mensa. This star has a high proper motion. The apparent magnitude is 5.67, which can be visible to the naked eye in exceptionally dark, cle ...
See also
References
{{Portal bar, Astronomy, Stars, Spaceflight, Outer space, Solar System
*List
Multiplanetary systems