GQ Lupi is a

T Tauri variable T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus star-forming region. They are found near molecular clouds and iden ...

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

approximately 495

light-year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s away in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

Lupus Lupus, technically known as systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Comm ...

. The star is young and has about 70% of the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

's mass.

Possible planetary system

In 2005, Ralph Neuhäuser and his colleagues reported a

substellar object A substellar object, sometimes called a substar, is an astronomical object the mass of which is smaller than the smallest mass at which hydrogen fusion can be sustained (approximately 0.08 solar masses). This definition includes brown dwarfs and fo ...

GQ Lupi b GQ Lupi b, or GQ Lupi B, is a possible extrasolar planet, brown dwarf or sub-brown dwarf orbiting the star GQ Lupi. Its discovery was announced in April 2005. Along with 2M1207b, this was one of the first extrasolar planet candidates to be dir ...

, orbiting the star. Along with

2M1207b 2M1207b is a planetary-mass object orbiting the brown dwarf 2M1207, in the constellation Centaurus, approximately 170 light-years from Earth.

, this was one of the first

extrasolar planet 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 ...

candidates to be directly imaged. The image was made with the VLT telescope at

Paranal Observatory Paranal Observatory is an astronomical observatory operated by the European Southern Observatory (ESO). It is located in the Atacama Desert of northern Chile on Cerro Paranal at altitude, south of Antofagasta. By total light-collecting area, it ...

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

, on June 25, 2004. Depending on its mass and the definition of a planet, GQ Lupi b may or may not be considered a planet. Is this a Brown Dwarf or an Exoplanet? New Young Sub-stellar Companion Imaged with the VLT
, ESO Press Release 09/05, April 7, 2005. Accessed on line June 13, 2008. As of 2006, 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 ...

Working Group on Extrasolar Planets described GQ Lupi b as a "possible planetary-mass companion to a young star." ''GQ Lupi b'' is listed as "confirmed planet" as in 2020.openexoplanetcatalogue.com GQ Lup
/ref> In 2020, another low-mass companion of GQ Lupi was discovered at a separation distance of about 16 arcseconds, or 2400 AU. Designated 2MASS J15491331-3539118 under the

2MASS The Two Micron All-Sky Survey, or 2MASS, was an astronomical survey of the whole sky in infrared light. It took place between 1997 and 2001, in two different locations: at the U.S. Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona, and ...

catalogue, it is likely a young stellar object that is gravitationally bound to its primary star. It is estimated to be approximately 15% the Sun's mass and 21% the Sun's radius. It has an effective temperature of about 3190 K, indicating that it is a

red dwarf ''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. T ...

with the spectral type M4.

References

External links

* The low-mass companion of GQ Lup, E.W. Guenther, R. Neuhaeuser, G. Wuchterl, M. Mugrauer, A. Bedalov, and P.H. Hauschildt, ''Astronomische Nachrichten'' 326, #10 (December 2005), pp. 958–963. . *R. Neuhaeuser (2005)
"Homogeneous comparison of directly detected planet candidates: GQ Lup, 2M1207, AB Pic"
arXiv:astro-ph/0509906v1. * * * * {{Stars of Lupus Planetary systems with one confirmed planet Lupus (constellation) T Tauri stars K-type main-sequence stars Lupi, GQ Durchmusterung objects