Discovery | |
---|---|
Discovered by | Bouchy et al. [1] |
Discovery site | La Silla Observatory |
Discovery date | December 9, 2008 [1] |
Doppler spectroscopy | |
Orbital characteristics | |
Apastron | 4.44 AU (664,000,000 km) |
Periastron | 1.56 AU (233,000,000 km) |
3.00 AU (449,000,000 km) [2] | |
Eccentricity | 0.48 ± 0.05 [2] |
2172 ± 158 [2] d 5.947 y | |
Average orbital speed | 15.1 |
2452154 ± 194 [2] | |
-30 ± 13 [2] | |
Star | HD 181433 |
HD 181433 d is an extrasolar planet located approximately 87 light years away [3] in the constellation of Pavo, orbiting the star HD 181433. This planet has a minimum mass of 0.54 Jupiter mass and takes 2172 days to orbit the star. The average orbital distance is 3.00 AU. At periastron distance, it will have distance from the star similar to Mars’ distance from the Sun at 1.56 AU. At apastron, the distance is 4.44 AU. These corresponds to the orbital eccentricity of 0.48. [2]
HD 188753 is a hierarchical triple star system approximately 151 light-years away in the constellation of Cygnus, the Swan. In 2005, an extrasolar planet was announced to be orbiting the primary star in the system. Follow-up measurements by an independent group in 2007 did not confirm the planet's existence.
HD 28185 b is an extrasolar planet 128 light-years away from Earth in the constellation of Eridanus. The planet was discovered orbiting the Sun-like star HD 28185 in April 2001 as a part of the CORALIE survey for southern extrasolar planets, and its existence was independently confirmed by the Magellan Planet Search Survey in 2008. HD 28185 b orbits its sun in a circular orbit that is at the inner edge of its star's habitable zone.
16 Cygni Bb or HD 186427 b is an extrasolar planet approximately 69 light-years away in the constellation of Cygnus. The planet was discovered orbiting the Sun-like star 16 Cygni B, one of two solar-mass (M☉) components of the triple star system 16 Cygni in 1996. It orbits its star once every 799 days and was the first eccentric Jupiter and planet in a double star system to be discovered. The planet is abundant in lithium.
HD 164922 b is an exoplanet orbiting the star HD 164922 about 72 light-years from Earth in the constellation Hercules. Its inclination is not known, and its true mass may be significantly greater than the radial velocity lower limit of 0.36 Jupiter masses. The planet also has a low eccentricity, unlike most other long period extrasolar planets – 0.05 – about the same as Jupiter and Saturn in the Solar System. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
Gliese 777 b, also known as Gliese 777 Ab or HD 190360 b, is an extrasolar planet approximately 52 light-years away in the constellation of Cygnus. The planet was discovered orbiting the primary star of the Gliese 777 system in June 2002 using the radial velocity method. The planet is at least one half more massive than Jupiter but roughly the same size as Jupiter. In 2021, the inclination of Gliese 777 Ab was measured via astrometry, allowing the true mass of 1.8 MJ to be determined.
HD 33564 b is an extrasolar planet located approximately 68 light-years away in the constellation of Camelopardalis. This planet orbits around F6V star HD 33564. The planet has an eccentric orbit, ranging in distance from 0.737 AU at periastron to 1.497 AU at apastron.
HD 156846 b is an extrasolar planet located approximately 160 light-years away in the constellation of Ophiuchus, orbiting the star HD 156846. It has one of the most eccentric planetary orbits known. The high eccentricity of this planet's orbit is probably attributable to the presence of a red dwarf companion star. The average distance of the planet from HD 156846 is 0.99 AU, nearly identical to the distance of Earth from the Sun. The distance ranges from 0.15 AU to 1.83 AU with a 360-day period, also very close to the period of the Earth. It is also very massive with at least 10.45 Jupiter masses. The mass is a lower limit because the inclination of the orbit is not known; if its inclination and hence true mass became known, it would probably be found to be a brown dwarf, or even a red dwarf.
HD 181433 is a star located approximately 87 light-years away in the constellation of Pavo. According to SIMBAD, it has a stellar classification of K3III-IV, which puts it on the borderline between being a red giant and a subgiant. This is inconsistent with the fact that its luminosity is only 0.308 times that of the Sun. Its entry in the Hipparcos catalogue lists a spectral type of K5V, classifying it as a dwarf star. As of 2008, three extrasolar planets are thought to be orbiting the star. There is currently little information on these planets. The name of this star comes from its identifier in the Henry Draper catalogue.
MOA-2007-BLG-192L is a low-mass red dwarf star or brown dwarf, approximately 3,000 light-years away in the constellation of Sagittarius. It is estimated to have a mass approximately 6% of the Sun's. In 2008, an Earth-sized extrasolar planet was announced to be orbiting this object.
HD 40307 c is an extrasolar planet orbiting the star HD 40307, located 42 light-years away in the direction of the southern constellation Pictor. The planet was discovered by the radial velocity method, using the HARPS apparatus, in June 2008. Of the six proposed planets in the HD 40307 star system, it is the third-largest, and has the second-closest orbit from the star. The planet is of interest as this star has relatively low metallicity, supporting a hypothesis that different metallicities in protostars determine what kind of planets they will form.
HD 47186 is a star located approximately 129 light-years away in the constellation of Canis Major. It is a G6V star with the characteristics very similar to the Sun, but it is 1.7 times more metal-rich. In 2008, two extrasolar planets were discovered orbiting the star.
HD 181433 b is an extrasolar planet located approximately 87 light years away in the constellation of Pavo, orbiting the star HD 181433. This planet has mass at least 7.56 times that of Earth. This planet is classified as a super-Earth and orbits at 0.080 AU and varies only about 0.063 AU with an eccentricity of 0.396. François Bouchy et al. have published a paper detailing the HD 181433 planetary system in Astronomy and Astrophysics.
HD 181433 c is an extrasolar planet located approximately 87 light-years away in the constellation of Pavo, orbiting the star HD 181433. This planet is at least 0.64 times as massive as Jupiter and takes 962 days to orbit the star at an orbital distance of 1.76 astronomical units (AU), or 263 gigametres (Gm). The orbit is eccentric, however, and ranges from 1.27 AU (190 Gm) at periastron to 2.25 AU (337 Gm) at apastron. François Bouchy et al. have published a paper detailing the HD 181433 planetary system in Astronomy and Astrophysics.
HD 154672 b is an extrasolar planet located approximately 210 light-years away in the constellation of Ara, orbiting the metal-rich and aged star HD 154672. This planet has a minimum mass five times that of Jupiter and orbits at about 60% the distance between the Earth to the Sun. Its orbit is very elliptical, which causes temperatures on the planet to vary significantly as it proceeds along its orbit. This planet was discovered in Las Campanas Observatory on September 5, 2008 using the radial velocity method. Along with HD 205739 b, the planets were the first to be discovered by the N2K Consortium using the Magellan Telescopes.
HD 60532 b is an extrasolar planet located approximately 84 light-years away in the constellation of Puppis, orbiting the star HD 60532. This planet has a true mass of 3.15 times more than Jupiter, orbits at 0.77 AU, and takes 201.83 days to revolve in an eccentric orbit. This planet was discovered on September 22, 2008 in La Silla Observatory using the HARPS spectrograph. On this same day, the second planet in this system, HD 60532 c, was discovered in a 1:3 orbital resonance.
BD-17°63 b, formally named Finlay, is an extrasolar planet located approximately 112.5 light-years away in the constellation of Cetus, orbiting the 10th magnitude K-type main sequence star BD-17°63. This planet has a minimum mass of 5.1 MJ and orbits at a distance of 1.34 astronomical units from the star. The distance ranges from 0.62 AU to 2.06 AU, corresponding to the eccentricity of 0.54. One revolution takes about 656 days.
HD 153950 b, also known as Trimobe, is an extrasolar planet located approximately 162 light-years away. This planet was discovered on October 26, 2008 by Moutou et al. using the HARPS spectrograph on ESO's 3.6 meter telescope installed at La Silla Observatory in Atacama desert, Chile.
HD 20868 b is an extrasolar planet located approximately 156 light-years away in the constellation of Fornax, orbiting the 10th magnitude K-type subgiant star HD 20868. This planet has a minimum mass of 1.99 times more than Jupiter and orbits at a distance of 0.947 AU. This planet takes 380.85 days or 12.5 months to revolve around the star with an eccentricity of 0.75, one of the most eccentric of any known extrasolar planets. At periastron, the distance is 0.237 AU and at apastron, the distance is 1.66 AU.
An exoplanet is a planet located outside the Solar System. The first evidence of an exoplanet was noted as early as 1917, but was not recognized as such until 2016; no planet discovery has yet come from that evidence. What turned out to be the first detection of an exoplanet was published among a list of possible candidates in 1988, though not confirmed until 2003. The first confirmed detection came in 1992, with the discovery of terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method and the radial-velocity method. As of 1 December 2023, there are 5,550 confirmed exoplanets in 4,089 planetary systems, with 887 systems having more than one planet. This is a list of the most notable discoveries.
HD 240237 b is a super-Jupiter exoplanet orbiting the K-type giant star HD 240237 about 4,900 light-years (1,500 parsecs, or nearly 4.6×1016 km) away from Earth in the constellation Cassiopeia. It orbits outside of the habitable zone of its star at a distance of 1.9 AU. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star. The planet has a mildly eccentric orbit.