Discovery | |
---|---|
Discovered by | Neuhäuser et al. |
Discovery site | ESO's Paranal Observatory, Chile |
Discovery date | April 2005 |
Imaged | |
Orbital characteristics | |
Star | GQ Lupi |
Physical characteristics | |
4.6±1.4 [1] RJ | |
Mass | 1 – 36 [1] [2] MJ |
Temperature | 2650 ± 100, [2] (2050±350–2400) [3] K |
GQ Lupi b, or GQ Lupi B, [4] [5] is a possible extrasolar planet, brown dwarf or sub-brown dwarf orbiting the star GQ Lupi. Its discovery was announced in April 2005, less than a month before the full confirmation of 2M1207b was announced. Along with 2M1207b, this was one of the first extrasolar planet candidates to be directly imaged. The image was made with the European Southern Observatory's VLT telescope at the Paranal Observatory, Chile on June 25, 2004. [6] [7]
GQ Lupi b has a spectral type between M6 and L0, corresponding to a temperature between 2,050 and 2,650 kelvins. [2] Located at a projected distance of about 100 AU from its companion star, giving it an orbital period of perhaps about 1,200 years, it is believed to be several times more massive than Jupiter. Because the theoretical models which are used to predict planetary masses for objects in young star systems like GQ Lupi b are still tentative, the mass cannot be precisely specified — models place GQ Lupi b's mass anywhere between a few Jupiter masses and 36 Jupiter masses. [2] At the highest end of this range, GQ Lupi b could be classified as a small brown dwarf, but at the lowest end of this range, it could be classified as an extremely large Jupiter-like exoplanet rather than a brown dwarf.
As of 2006, the International Astronomical Union Working Group on Extrasolar Planets described GQ Lupi b as a "possible planetary-mass companion to a young star." [8] GQ Lupi b is listed as a "confirmed planet" as of 2020. [9]
Emission by hydrogen in the near-infrared (paschen beta) was first detected in 2007 with the Very Large Telescope (VLT). This was interpreted as a sign of accretion of material from a disk. [10] Additionally H-alpha emission was detected with Hubble. [11] H-alpha was also detected with the Magellan Telescope, but the disk was not detected with ALMA. [12] An analysis of additional VLT data showed a mutual inclination with the circumstellar disk of 84 ± 9°. This hints to a turbulent formation of the disk around GQ Lupi b. The researchers suspect the disk to be in a transitional stage in which satellites (similar to exomoons) opened a gap within the disk, indicating a late stage of the disk. The accretion rate was estimated to be 10-6.5 MJ/year. [13] A study from 2023 with additional VLT data found the emission line to be variable on timescales of several months to decades. The observations were consistent with magnetospheric accretion. [14] Mid-infrared observations with JWST MIRI did not show any silicate features from the disk. This indicates grain growth and dust settling. Additionally the disk could have an inner cavity that is larger than allowed by sublimation. [15]
2M1207, 2M1207A or 2MASS J12073346–3932539 is a brown dwarf located in the constellation Centaurus; a companion object, 2M1207b, may be the first extrasolar planetary-mass companion to be directly imaged, and is the first discovered orbiting a brown dwarf.
Rho Coronae Borealis is a yellow dwarf star 57.1 light-years away in the constellation of Corona Borealis. The star is thought to be similar to the Sun with nearly the same mass, radius, and luminosity. It is orbited by four known exoplanets.
GQ Lupi is a T Tauri variable star approximately 495 light-years away in the constellation of Lupus. The star is young and has about 70% of the Sun's mass.
2M1207b is a planetary-mass object orbiting the brown dwarf 2M1207, in the constellation Centaurus, approximately 170 light-years from Earth. It is one of the first candidate exoplanets to be directly observed. It was discovered in April 2004 by the Very Large Telescope (VLT) at the Paranal Observatory in Chile by a team from the European Southern Observatory led by Gaël Chauvin. It is believed to be from 5 to 6 times the mass of Jupiter and may orbit 2M1207 at a distance roughly as far from the brown dwarf as Pluto is from the Sun.
AB Pictoris is a K-type main-sequence star, located 163.5 light-years away in the southern constellation of Pictor. It has been identified as a member of the young Tucana–Horologium association. The star has been classified as a BY Draconis variable, indicating it has an active chromosphere. It is an X-ray source and displays emission lines in its spectrum.
Gliese 86 is a K-type main-sequence star approximately 35 light-years away in the constellation of Eridanus. It has been confirmed that a white dwarf orbits the primary star. In 1998 the European Southern Observatory announced that an extrasolar planet was orbiting the star.
HD 100546, also known as KR Muscae, is a pre-main sequence star of spectral type B8 to A0 located 353 light-years from Earth in the southern constellation of Musca. The star is surrounded by a circumstellar disk from a distance of 0.2 to 4 AU, and again from 13 AU out to a few hundred AU, with evidence for a protoplanet forming at a distance of around 47 AU.
Beta Pictoris b (abbreviated as β Pic b) is an exoplanet orbiting the young debris disk A-type main sequence star Beta Pictoris located approximately 63 light-years (19.4 parsecs, or 6×1014 km) away from Earth in the constellation of Pictor. It has a mass around 13 Jupiter masses and a radius around 46% larger than Jupiter's. It orbits at 9 AU from Beta Pictoris, which is about 3.5 times farther than the orbit of Beta Pictoris c. It orbits close to the plane of the debris disk orbiting the star, with a low eccentricity and a period of 20–21 years.
Spectro-Polarimetric High-contrast Exoplanet REsearch (VLT-SPHERE) is an adaptive optics system and coronagraphic facility at the Very Large Telescope (VLT). It provides direct imaging as well as spectroscopic and polarimetric characterization of exoplanet systems. The instrument operates in the visible and near infrared, achieving exquisite image quality and contrast over a small field of view around bright targets.
PDS 70 is a very young T Tauri star in the constellation Centaurus. Located 370 light-years from Earth, it has a mass of 0.76 M☉ and is approximately 5.4 million years old. The star has a protoplanetary disk containing two nascent exoplanets, named PDS 70b and PDS 70c, which have been directly imaged by the European Southern Observatory's Very Large Telescope. PDS 70b was the first confirmed protoplanet to be directly imaged.
A circumplanetary disk is a torus, pancake or ring-shaped accumulation of matter composed of gas, dust, planetesimals, asteroids or collision fragments in orbit around a planet. They are reservoirs of material out of which moons may form. Such a disk can manifest itself in various ways.
K2-24 is a metal-rich G3-type main sequence star larger and more massive than the Sun, located 560 light-years away in the constellation Scorpius. Two confirmed transiting exoplanets are known to orbit this star. An attempt to detect stellar companions using adaptive optics imaging at the Keck telescope was negative however later observations using lucky imaging at the Danish 1.54 m telescope at La Silla Observatory detected a possible companion at 3.8 arcseconds distance from K2-24. This candidate companion being over 8 magnitudes fainter than K2-24 and with a color temperature of 5400 Kelvin, is inconsistent with a bound main sequence companion.
Delorme 1 is a binary star with a planetary-mass companion (PMC) or protoplanet in a circumbinary orbit. The PMC is notable for showing signs of accretion, despite being 30-45 Myr old, making it similar to Peter Pan disks. These disks show characteristics of a gas-rich disk at unexpected high ages.
Media related to GQ Lupi b at Wikimedia Commons