Discovery [1] | |
---|---|
Discovered by | Naef et al. |
Discovery site | La Silla Observatory |
Discovery date | October 19, 2009 |
radial velocity (HARPS) | |
Orbital characteristics [1] | |
2.15 AU (322,000,000 km) | |
Eccentricity | 0.81+0.05 −0.02 |
1,116±26 d | |
2,454,049+43 −55 JD | |
301° +3° −4° | |
Semi-amplitude | 37.3+5.1 −0.9 m/s |
Star | HD 28254 |
Physical characteristics | |
Mean radius | 1.21 RJ |
Mass | 1.16+0.10 −0.06 MJ [1] |
34.93 m/s2 | |
Temperature | 207+13 −40 K |
HD 28254 b (also known as HIP 20606 b) is an extrasolar planet which orbits the G-type main sequence star HD 28254, located approximately 178 light years away in the constellation Dorado.
The planet was discovered in a survey by HARPS along with 29 other planets in 2009. [1]
Due to the planets high mass, it's assumed to be a gas giant like Jupiter. Since HD 28254 was detected indirectly, properties such as its inclination, radius, and temperature are unknown. HD 28254 takes about 3 years to orbit its host. However, the planet has one of the most eccentric orbits around a star.
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 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.
HD 181433 d is an extrasolar planet located approximately 87 light years away 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.
HD 181720 is an 8th-magnitude G-type main sequence star located approximately 190 light-years away in the constellation Sagittarius. This star is larger, hotter, brighter and less massive than the Sun. Also its metal content is three-tenths as much as the Sun.
HD 190984 b is an extrasolar planet which orbits the F-type main sequence star HD 190984, located approximately 330 light years away in the constellation Pavo. This planet is at least three times more massive than Jupiter and takes 13 years and four-and-a-half months to orbit the star at a semimajor axis of 5.5 AU with an eccentricity of 0.57. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 6718 is a solar twin star in the equatorial constellation of Cetus. It has a yellow hue but is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.45. The distance to this object, as determined from parallax measurements, is 168 light years. It is drifting away from the Sun with a radial velocity of +35 km/s.
HD 8535 is a star located 181 light years away from the Sun in the southern constellation of Phoenix. It has a yellow hue and can be viewed using binoculars or a small telescope, having a low apparent visual magnitude of 7.70. The star is drifting further away from the Sun with a radial velocity of +2.4 km/s.
HD 8535 b is an extrasolar planet which orbits the G-type main sequence star HD 8535, located approximately 171 light years away in the constellation Phoenix. This planet has at least five-eighths the mass of Jupiter and takes 3.6 years to orbit the star at a semimajor axis of 2.47 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 28254 is an 8th magnitude G-type main sequence star located 180 light years away in the constellation Dorado. This star is larger, cooler, brighter, and more massive than the Sun, and its metal content is 2.3 times as much as the Sun. In 2009, a gas giant planet was found in orbit around the star.
HD 290327 is a single star in the equatorial constellation of Orion. It has a yellow hue with an apparent visual magnitude of 8.99, which is too faint to be viewed with the naked eye. Parallax measurements provide a distance estimate of 184 light years from the Sun. It is drifting away with a radial velocity of +29.5 km/s, having come to within 124 light-years around a million years ago.
HD 290327 b is an extrasolar planet which orbits the G-type subgiant star HD 290327, located approximately 180 light years away in the constellation Orion. This planet has at least five halves the mass of Jupiter and takes 6.7 years to orbit the star at a semimajor axis of 3.35 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 43197 is a star with an exoplanetary companion in the southern constellation of Canis Major. It has been given the proper name Amadioha, as selected by Nigeria during the NameExoWorlds campaign that celebrated the 100th anniversary of the IAU. Amadioha is the god of thunder in Igbo mythology. It has an apparent visual magnitude of 8.98, meaning this is a ninth magnitude star that is too dim to be visible to the naked eye. The system is located at a distance of 204 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +72 km/s. It made its closest approach some 583,000 years ago when it came to within 87 light-years.
HD 43197 b is an extrasolar planet which orbits the G-type main sequence or subgiant star HD 43197, located approximately 204 light years away in the constellation Canis Major. This planet has a minimum mass 55% that of Jupiter and takes 0.85 years to orbit the star at a semimajor axis of 0.882 AU. Its has a high eccentricity of 0.74, but its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 44219 is a solar-type star with an exoplanetary companion in the equatorial constellation of Monoceros. It has an apparent visual magnitude of 7.69, making it an 8th magnitude star that is too faint to be readily visible to the naked eye. The system is located at a distance of 173 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −12 km/s.
HD 44219 b is an extrasolar planet which orbits the G-type main sequence star HD 44219, located approximately 164 light years away in the constellation Monoceros. This planet has at least three-fifths the mass of Jupiter and takes 1.29 years to orbit the star at a semimajor axis of 1.18 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 148156 is an 8th magnitude G-type main sequence star located approximately 168 light years away in the constellation Norma. This star is larger, hotter, brighter, and more massive than the Sun, and its metal content is almost twice as much.
HD 148156 b is an extrasolar planet which orbits the G-type main sequence star HD 148156, located approximately 168 light years away in the constellation Norma. This planet has at least nine-tenths the mass of Jupiter and takes 25 ninths years to orbit the star at a semimajor axis of 2.06 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
HD 156411 is a 7th magnitude G-type main-sequence star located approximately 186 light years away in the southern constellation Ara. This star is larger, hotter, brighter, and more massive than the Sun. Its metal content is three-fourths as much as the Sun. The star is around 4.3 billion years old and is spinning with a projected rotational velocity of 1.8 km/s. Naef and associates (2010) noted the star appears to be slightly evolved, and thus may be in the process of leaving the main sequence. In 2009, a gas giant planet was found in orbit around the star.
HD 156411 b is an extrasolar planet which orbits the G-type main sequence star HD 156411, located approximately 179 light years away in the constellation Ara. This planet has at least three-fourths the mass of Jupiter and takes eight-thirds years to orbit the star at a semimajor axis of 1.81 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
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 May 2023, there are 5,366 confirmed exoplanets in 3,962 planetary systems, with 856 systems having more than one planet. This is a list of the most notable discoveries.