NASA's Hubble Reveals Rogue Planetary Orbit For Fomalhaut B

There are known

exoplanet 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 ...

s, or planets outside 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 ...

that orbit a star, as of ; only a small fraction of these are located in the vicinity of the Solar System. Within , there are 97 exoplanets listed as confirmed by the

NASA Exoplanet Archive The NASA Exoplanet Archive is an online astronomical exoplanet catalog and data service that collects and serves public data that support the search for and characterization of extra-solar planets (exoplanets) and their host stars. It is part of ...

. Among the over 500 known stars and

brown dwarf Brown dwarfs (also called failed stars) are substellar objects that are not massive enough to sustain nuclear fusion of ordinary hydrogen ( 1H) into helium in their cores, unlike a main-sequence star. Instead, they have a mass between the most ...

s within 10 parsecs, around 60 have been confirmed to have planetary systems; 51 stars in this range are visible to the naked eye, eight of which have planetary systems. The first report of an exoplanet within this range was in 1998 for a planet orbiting around

Gliese 876 Gliese 876 is a red dwarf approximately 15 light-years away from Earth in the constellation of Aquarius. It is one of the closest known stars to the Sun confirmed to possess a planetary system with more than two planets, after Gliese 1061 ...

(15.3 light-years (ly) away), and the latest as of 2022 is one around

EQ Pegasi EQ Pegasi (also known as Gliese 896) is a nearby binary system of two red dwarfs. Both components are flare stars, with spectral types of M4Ve and M6Ve respectively, and a current separation between the components of 5.8 arcseconds. ...

A (20 ly). The closest exoplanet found is

Proxima Centauri b Proxima Centauri b (or Proxima b), sometimes referred to as Alpha Centauri Cb, is an exoplanet orbiting in the habitable zone of the red dwarf star Proxima Centauri, which is the closest star to the Sun and part of the triple star system ...

, which was confirmed in 2016 to orbit

Proxima Centauri Proxima Centauri is a small, low-mass star located away from the Sun in the southern constellation of Centaurus. Its Latin name means the 'nearest tarof Centaurus'. It was discovered in 1915 by Robert Innes and is the nearest-kno ...

, the closest star to the Solar System (4.25 ly).

HD 219134 HD 219134 (also known as Gliese 892 or HR 8832) is a main-sequence star in the constellation of Cassiopeia. It is smaller and less luminous than the Sun, with a spectral class of K3V, which makes it an orange-hued star. HD 219134 is rel ...

(21.6 ly) has six exoplanets, the highest number discovered for any star within this range. Most known nearby exoplanets orbit close to their stars. A majority are significantly larger than Earth, but a few have similar masses, including planets around YZ Ceti, Gliese 367, and Proxima Centauri which may be less massive than Earth. Several confirmed exoplanets are hypothesized to be potentially habitable, with Proxima Centauri b and

Gliese 667 Cc Gliese 667 Cc (also known as GJ 667Cc, HR 6426Cc, or HD 156384Cc) is an exoplanet orbiting within the habitable zone of the red dwarf star Gliese 667 C, which is a member of the Gliese 667 triple star system, approximately away in the constella ...

(23.6 ly) considered among the most likely candidates. The

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

has assigned proper names to some known extrasolar bodies, including nearby exoplanets, through the

NameExoWorlds NameExoWorlds (also known as IAU NameExoWorlds) is the name of various projects managed by the International Astronomical Union (I.A.U.) to encourage names to be submitted for astronomical objects, which would later be considered for official ad ...

project. Planets named in the 2015 event include the planets around

Epsilon Eridani Epsilon Eridani ( Latinized from ε Eridani), formally named Ran, is a star in the southern constellation of Eridanus, at a declination of 9.46° south of the celestial equator. This allows it to be visible from most of Earth's surf ...

(10.5 ly) and

Fomalhaut Fomalhaut is the brightest star in the southern constellation of Piscis Austrinus, the "Southern Fish", and one of the brightest stars in the night sky. It has the Bayer designation Alpha Piscis Austrini, which is Latinized from � ...

, while planets that will be named in the 2022 event include those around

Gliese 436 Gliese 436 is a red dwarf approximately away in the zodiac constellation of Leo. It has an apparent visual magnitude of 10.67, which is much too faint to be seen with the naked eye. However, it can be viewed with even a modest telescope ...

, Gliese 486, and Gliese 367.

Exoplanets within 10 parsecs

Excluded objects

Unlike for bodies within the

, there is no clearly established method for officially recognizing an exoplanet. According to the

, an exoplanet should be considered confirmed if it has not been disputed for five years after its discovery. There have been examples where the existence of exoplanets has been proposed, but even after follow-up studies their existence is still considered doubtful by some astronomers. Such cases include

Wolf 359 Wolf 359 is a red dwarf star located in the constellation Leo, near the ecliptic. At a distance of approximately 7.9 light years from Earth, it has an apparent magnitude of 13.54 and can only be seen with a large telescope. Wolf 359 i ...

(7.9 ly, in 2019),

LHS 288 LHS 288 (Luyten 143-23) is a red dwarf around 15.8 light years from the Sun, the closest in the constellation Carina (constellation), Carina (near Eta Carinae). It is far too faint to be seen with the Naked eye astronomy, unaided eye, wit ...

(15.8 ly, in 2007), 40 Eridani A (16.3 ly, in 2018), and Gliese 1151 (26.2 ly, in 2021). There are also several instances where proposed exoplanets were later disproved by subsequent studies, including candidates around Alpha Centauri B (4.36 ly),

Barnard's Star Barnard's Star is a red dwarf about six light-years from Earth in the constellation of Ophiuchus. It is the fourth-nearest-known individual star to the Sun after the three components of the Alpha Centauri system, and the closest star in t ...

(5.96 ly),

Kapteyn's Star Kapteyn's Star is a class M1 red subdwarf about 12.83 light-years from Earth in the southern constellation Pictor; it is the closest halo star to the Solar System. With a magnitude of nearly 9 it is visible through binoculars or a te ...

(12.8 ly),

Van Maanen 2 Van Maanen 2, or van Maanen's Star, is the closest known solitary white dwarf to the solar system. It is a dense, compact stellar remnant no longer generating energy and has equivalent to about 68% of the Sun's mass but only 1% of its ...

(14.1 ly),

Groombridge 1618 Groombridge 1618 is a star in the northern constellation Ursa Major. With an apparent visual magnitude of +6.6, it lies at or below the threshold of stars visible to the naked eye for an average observer. It is relatively close to Eart ...

(15.9 ly), AD Leonis (16.2 ly),

Gliese 682 Gliese 682 or GJ 682 is a red dwarf. It is listed as the 49th-nearest known star to the Sun, being about 16 light years away from the Earth. Even though it is close by, it is dim with a magnitude of 10.95 and thus requires a telescope ...

(16.3 ly),

VB 10 VB 10 or Van Biesbroeck's star is a very small and very dim red dwarf located in the constellation Aquila. It is part of a binary star system. VB 10 is historically notable as it was the coolest, least massive and least luminous k ...

(19.3 ly), and

(25.1 ly). In 2021, a candidate planet was detected around

Vega Vega is the brightest star in the northern constellation of Lyra. It has the Bayer designation α Lyrae, which is Latinised to Alpha Lyrae and abbreviated Alpha Lyr or α Lyr. This star is relatively close at only from the Sun, an ...

, though it has yet to be confirmed. Another candidate planet, Candidate 1, was directly imaged around Alpha Centauri A, though it may also be a clump of asteroids or an artifact of the discovery mechanism. The Working Group on Extrasolar Planets of the International Astronomical Union adopted in 2003 a working definition on the upper limit for what constitutes a planet: not being massive enough to sustain thermonuclear fusion of

deuterium Deuterium (or hydrogen-2, symbol or deuterium, also known as heavy hydrogen) is one of two Stable isotope ratio, stable isotopes of hydrogen (the other being Hydrogen atom, protium, or hydrogen-1). The atomic nucleus, nucleus of a deuterium ato ...

. Some studies have calculated this to be somewhere around 13 times the

mass of Jupiter 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 ...

, and therefore objects more massive than this are usually classified as

s. Some proposed candidate exoplanets were later shown to be massive enough to fall above the threshold, and are likely brown dwarfs, as was the case for: SCR 1845-6357 B (13.1 ly), SDSS J1416+1348 B (30.3 ly), and

WISE 1217+1626 B WISEPC J121756.91+162640.2 (designation abbreviated to WISE 1217+1626, or WISE J1217+1626) is a binary brown dwarf system of spectral classes T9 + Y0, located in constellation Coma Berenices at approximately 30.4 light-years from Earth ...

(30 ly). Excluded from the current list are known examples of potential free-floating sub-brown dwarfs, or "

rogue planet A rogue planet (also termed a free-floating planet (FFP), interstellar, nomad, orphan, starless, unbound or wandering planet) is an interstellar object of planetary-mass, therefore smaller than fusors (stars and brown dwarfs) and without a h ...

s", which are bodies that are too small to undergo fusion yet they do not revolve around a star. Known such examples include: WISE 0855–0714 (7.4 ly), UGPS 0722-05, (13.4 ly) WISE 1541−2250 (18.6 ly), and SIMP J01365663+0933473 (20.0 ly).

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* * * * * * * * {{featured list Planetary systems Nearest nearest exoplanets

Exoplanets within 10 parsecs

Excluded objects

See also

Notes

References

External links