![]() Artist's conception | |
Discovery | |
---|---|
Discovered by | Udry et al. |
Discovery site | California, United States |
Discovery date | 22 August 2005 |
Doppler Spectroscopy | |
Orbital characteristics | |
Apastron | 0.115 AU (17,200,000 km) |
Periastron | 0.115 AU (17,200,000 km) |
0.115 ± 0.096 AU (17,200,000 ± 14,400,000 km) | |
Eccentricity | 0.00 ± 0.01 |
15.56 ± 0.02 d 0.04260 y | |
2,453,314.70 ±2.0 | |
359±47 | |
Semi-amplitude | 4.07 ± 0.2 |
Star | HD 4308 |
Physical characteristics | |
Mass | >0.0442 MJ (>14 MEarth) |
HD 4308 b is a low-mass exoplanet orbiting around HD 4308. It is believed to have almost no orbital eccentricity. [1]
HD 189733, also catalogued as V452 Vulpeculae, is a binary star system approximately 64.5 light-years away in the constellation of Vulpecula. The primary star is suspected to be an orange dwarf star, while the secondary star is a red dwarf star. Given that this system has the same visual magnitude as HD 209458, it promises much for the study of close transiting extrasolar planets. The star can be found with binoculars 0.3 degrees east of the Dumbbell Nebula (M27).
HD 4308 is a single star in the southern constellation of Tucana. It has a yellow hue and is a challenge to view with the naked eye even under good seeing conditions, having an apparent visual magnitude of 6.54. This object is located at a distance of 72 light years, as determined from parallax measurements. It is a population II star and is considered to be a member of the thick disk. The star is receding from the Sun with a radial velocity of +95 km/s.
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.
HD 11964 c is an extrasolar planet approximately 110 light-years away in the constellation of Cetus. The planet was discovered in a close-orbit around the yellow subgiant star HD 11964. The planet has a minimum mass 35 times the mass of Earth and is located in a mildly eccentric orbit which takes almost 38 days to complete. HD 11964 c was a possible planet discovered on the same day as HD 11964 b in 2005. HD 11964 c was first proposed in a paper published in 2007, and finally confirmed with new data presented in a review of multi-planet systems which appeared on the arXiv preprint website in 2008.
HD 11964 b is an extrasolar planet, a gas giant like Jupiter approximately 110 light-years away in the constellation of Cetus. The planet orbits the yellow subgiant star HD 11964 in a nearly-circular orbit, taking over 5 years to complete a revolution around the star at a distance of 3.34 astronomical units.
HD 189733 b is an exoplanet approximately 64.5 light-years (19.8 pc) away from the Solar System in the constellation of Vulpecula. Astronomers in France discovered the planet orbiting the star HD 189733 on October 5, 2005, by observing its transit across the star's face. With a mass 16.2% higher than that of Jupiter and a radius 13.8% greater, HD 189733 b orbits its host star once every 2.2 days at an orbital speed of 152.5 kilometers per second, making it a hot Jupiter with poor prospects for extraterrestrial life.
HD 4203 is a single star in the equatorial constellation of Pisces, near the northern constellation border with Andromeda. It has a yellow hue and is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.70. The distance to this object is 266 light years based on parallax, but it is drifting closer to the Sun with a radial velocity of −14 km/s.
HD 4203 b is an exoplanet more massive than Jupiter. It orbits two times further from the star than Earth to the Sun. The planet takes 1.1824 year to orbit the star very eccentrically from 1.00 AU to 3.14 AU. The planet was discovered by Steve Vogt using the Keck telescope.
HD 222582 b is an extrasolar planet that is 8.37 times the mass of Jupiter orbiting the star HD 222582. The orbital period is 572 days and orbits at a semimajor axis of 1.35 AU in one of the most eccentric orbits of any known planets.
HD 117618 b, named Noifasui by the IAU, is an exoplanet discovered orbiting the star HD 117618 in September 2004. The planet is a small gas giant less than a fifth the mass of Jupiter. It orbits close to its star in a very eccentric orbit.
HD 142022 Ab is an exoplanet discovered by the radial velocity method by Eggenberger et al. in 2005 after finding that HD 142022 A is wobbling which indicated the presence of a massive planet, designating as HD 142022 Ab, with mass of 4.5 times Jupiter. It has a relatively wide separation between a planet and a star with nearly 3 AU, which takes 1928 days or 5.28 years to revolve. As it is typical for long-period planets, it has a relatively high eccentricity of 53±20%.
HD 121504 b is an exoplanet that is likely to be slightly less massive than Jupiter. Although the radial velocity method that was used to detect the planet can only measure the minimum mass of the planet, it is very unlikely that its true mass would be much higher.
HD 40979 b is an extrasolar planet orbiting the star HD 40979, was detected from the Lick and Keck observatories and photometric observations at Fairborn Observatory reveal low-amplitude brightness variations in HD 40979. It is thought to be a large gas giant planet. It was discovered in 2002 by Debra Fischer.
HD 49674 b is an extrasolar planet located approximately 134 light-years away in the constellation of Auriga, orbiting the star HD 49674. This planet was discovered orbiting the star in 2002. The planet is a gas giant and orbits extremely close to its star, which takes only 4.95 days to revolve.
HD 89307 b is an extrasolar planet orbiting the star HD 89307 located approximately 108 light-years away in the constellation of Leo. The planet takes 187 megaseconds to orbit. The planet's minimum mass is 1.92 MJ since the inclination is unknown. As it is typical for most of the long-period planets, the eccentricity is greater than any planets in the Solar System, orbiting at the average distance of 491 gigameters. The speed of the wobble caused by the planet's gravity is 31 meters per second. The average orbital velocity is 16.6 m/s.
HD 102117 b, formally named Leklsullun, is a planet that orbits the star HD 102117. The planet is a small gas giant a fifth the size of Jupiter. It orbits very close to its star, but not in a "torch orbit" like the famous 51 Pegasi b. It is one of the smallest extrasolar planets discovered so far.
HD 153950 b 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 4313 b is an extrasolar planet orbiting the K-type star HD 4313 approximately 447 light years away in the constellation Pisces. This planet was discovered using the Doppler spectroscopy method.
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 October 2022, there are 5,197 confirmed exoplanets in 3,833 planetary systems, with 840 systems having more than one planet. This is a list of the most notable discoveries.
HD 89345 b is a Neptune-like exoplanet that orbits a G-type star. It is also called K2-234b. Its mass is 35.7 Earths, it takes 11.8 days to complete one orbit of its star, and is 0.105 AU from its star. It was discovered by 43 astrophysicists, one which is V. Van Eylen, and is announced in 2018.