GQ Lupi
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Observation data Epoch J2000.0 |
|
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Constellation | Lupus |
Right ascension | 15h 49m 12.14s |
Declination | -35° 39' 03.9" |
Apparent magnitude (V) | +11.4 |
Spectral Characteristics | |
Spectral type | K7V |
U-B color index | ? |
B-V color index | ? |
Variable type | T Tauri variable |
Astrometry | |
Radial velocity (Rv) | ? km/s |
Proper motion (μ) | RA: ? mas/yr Dec.: ? mas/yr |
Parallax (π) | ? ± ? mas |
Distance | 400 ly (123 pc) |
Absolute magnitude (MV) | ? |
Physical Characteristics | |
Mass | 0.7 M☉ |
Radius | 1.57 R☉ |
Luminosity | ? L☉ |
Temperature | 4350 K |
Metallicity | ? |
Rotation | ? |
Age | <2 Million years |
Other designations | |
CD-35°10525
|
GQ Lupi is a star in the constellation Lupus. GQ Lupi is a young (2 million years old) main sequence variable star with about 70% of the Sun's mass and is about 400 light years away from Earth. A companion object discovered in 2005, GQ Lupi b, if confirmed to be a planet, may be the first directly imaged extrasolar planet.
[edit] GQ Lupi b
Extrasolar planet | Lists of extrasolar planets | |
---|---|---|
Observed position | ||
Observed separation | (d) | 103 ± 37 AU |
Physical characteristics | ||
Mass | (m) | 1 – 42 MJ |
Radius | (r) | 1.2 ± 0.6 RJ |
Density | (ρ) | ? kg/m3 |
Temperature | (T) | 1600 – 2520 K |
Discovery information | ||
Discovery date | 2005 | |
Discoverer(s) | Neuhäuser et al. | |
Detection method | Imaged | |
Discovery status | Confirmed |
GQ Lupi b is a possible extrasolar planet orbiting the star GQ Lupi. At its discovery in 2005, it was believed to be the first extrasolar planet to be directly imaged, although 2M1207b may also claim that distinction. The image was made with the VLT telescope at Paranal Observatory, Chile in April 2005.
Located at a distance of about 100 AU from its companion star, giving it an orbital period of about 1200 years, GQ Lupi b 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 precisly specified -- although most estimates give a mass of about 2 to 3 times that of Jupiter, other models place GQ Lupi b's mass anywhere between 1 and 42 Jupiter masses. At the highest end of this range, GQ Lupi b would be classified as a small brown dwarf in a binary star system rather than as an exoplanet. The object has a spectral type between M9 and L4, corrseponding to a temperature between 1600 and 2500 kelvins.
As of May 2005, the International Astronomical Union describes GQ Lupi b as a "possible planetary-mass companion to a young star."
[edit] References
- E.W. Guenther et al. (2005). "The low-mass companion of GQ Lup". (Preprint)
- R. Neuhaeuser (2005). "Homogeneous comparison of directly detected planet candidates: GQ Lup, 2M1207, AB Pic". (Preprint)
[edit] External links
- New Scientist: First image of exoplanet orbiting Sun-like star
- Extrasolar Planets Encyclopedia: Profile on GQ Lupi system
- The Planetary Society: Striking Image Could Be First Picture Ever of Extrasolar Planet
- BBC: Telescopes see 'distant planet'
- SPACE.com: Fresh Debate over First Photo of Extrasolar Planet