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HD 169830 is a star in the southern constellation of Sagittarius. It has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of +5.90. The star is located at a distance of 120 light years from the Sun based on parallax. It is drifting closer with a radial velocity of −17.3 km/s, and is predicted to come as close as 20.7 ly (6.4 pc) in 2.08 million years. HD 169830 is known to be orbited by two large Jupiter-like exoplanets.
54 Piscium is an orange dwarf star approximately 36 light-years away in the constellation of Pisces. In 2003, an extrasolar planet was confirmed to be orbiting the star, and in 2006, a brown dwarf was also discovered orbiting it.
79 Ceti, also known as HD 16141, is a binary star system located 123 light-years from the Sun in the southern constellation of Cetus. It has an apparent visual magnitude of +6.83, which puts it below the normal limit for visibility with the average naked eye. The star is drifting closer to the Earth with a heliocentric radial velocity of −51 km/s.
HD 46375 is double star with an exoplanetary companion in the equatorial constellation of Monoceros. It presents as an 8th-magnitude star with an apparent visual magnitude of 7.91, which is too dim to be readily visible to the naked eye. The system is located at a distance of 96.5 light-years from the Sun based on parallax measurements, but is slowly drifting closer with a radial velocity of −1 km/s. The common proper motion stellar companion, designated HD 46375 B, has a linear projected separation of 346±13 AU.
HD 179949 is a 6th magnitude star in the constellation of Sagittarius. It is a yellow-white dwarf, a type of star hotter and more luminous than the Sun. The star is located about 90 light years from Earth and might be visible under exceptionally good conditions to an experienced observer without technical aid; usually binoculars are needed.
HD 177830 is a 7th magnitude binary star system located approximately 205 light-years away in the constellation of Lyra. The primary star is slightly more massive than the Sun, but cooler being a type K star. Therefore, it is a subgiant clearly more evolved than the Sun. In visual light it is four times brighter than the Sun, but because of its distance, about 204 light years, it is not visible to the unaided eye. With binoculars it should be easily visible.
Gliese 876 c is an exoplanet orbiting the red dwarf Gliese 876, taking about 30 days to complete an orbit. The planet was discovered in April 2001 and is the second planet in order of increasing distance from its star.
Gliese 876 b is an exoplanet orbiting the red dwarf Gliese 876. It completes one orbit in approximately 61 days. Discovered in June 1998, Gliese 876 b was the first planet to be discovered orbiting a red dwarf.
79 Ceti b is an extrasolar planet orbiting 79 Ceti every 75 days. Discovered along with HD 46375 b on March 29, 2000, it was the joint first known extrasolar planet to have minimum mass less than the mass of Saturn.
109 Piscium b is a long-period extrasolar planet discovered in orbit around 109 Piscium. It is about 5.74 times the mass of Jupiter and is likely to be a gas giant. As is common for long-period planets discovered around other stars, it has an orbital eccentricity greater than that of Jupiter.
Epsilon Eridani b, also known as AEgir [sic], is an exoplanet approximately 10.5 light-years away orbiting the star Epsilon Eridani, in the constellation of Eridanus. The planet was discovered in 2000, and as of 2023 remains the only confirmed planet in its planetary system. It orbits at around 3.5 AU with a period of around 7.6 years, and has a mass around 0.6 times that of Jupiter. As of 2023, both the Extrasolar Planets Encyclopaedia and the NASA Exoplanet Archive list the planet as 'confirmed'.
HD 114762 b is a small red dwarf star, in the HD 114762 system, formerly thought to be a massive gaseous extrasolar planet, approximately 126 light-years (38.6 pc) away in the constellation of Coma Berenices. This optically undetected companion to the late F-type main-sequence star HD 114762 was discovered in 1989 by Latham, et al., and confirmed in an October 1991 paper by Cochran, et al. It was thought to be the first discovered exoplanet
The extrasolar planet, designated as HD 4208 b, was discovered by the California and Carnegie Planet Search team using the Keck telescope. The planet is probably somewhat less massive than Jupiter, although only its minimum mass is known. Its orbital distance is 1.67 AU, slightly further than Mars and its eccentricity is low.
HD 117207 b is an exoplanet orbiting at 3.77 astronomical units around HD 117207, taking about 7.14 years to complete its orbit. Its orbit has a low to moderate eccentricity. This planet was announced in January 2005 by Marcy at the Keck Observatory. HD 117207 b has a minimum mass of 1.88 Jupiter masses, and in 2023 its inclination and true mass were determined via astrometry.
HD 210277 b is an extrasolar planet orbiting the star HD 210277. It was discovered in September 1998 by the California and Carnegie Planet Search team using the highly successful radial velocity method. The planet is at least 24% more massive than Jupiter. The mean distance of the planet from the star is slightly more than Earth's distance from the Sun. However, the orbit is very eccentric, so at periastron this distance is almost halved, and at apastron it is as distant as Mars is from the Sun.
HD 30177 b is an extrasolar planet located approximately 181.6 light-years away in the constellation of Dorado, orbiting the star HD 30177.
HD 114729 b is an extrasolar planet approximately 114 light years away in the constellation of Centaurus. This planet is probably slightly less massive than Jupiter. It is an "eccentric Jupiter" meaning that it does not orbit very near the star like the famous 51 Pegasi b but further out and its orbit is very oval-shaped. The mean distance from the star is 2.11 AU, about twice the Earth's distance from the Sun. At periastron, the planet is only 1.43 AU from the star, and at apoastron, the orbital distance is 2.72 AU.
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 89307 b is an exoplanet orbiting the star HD 89307 located approximately 104 light-years away in the constellation of Leo. The planet takes roughly 2164 days or 5.9 years to orbit its star. The planet's minimum mass is 1.92 MJ; initially, the true mass could not be determined since the inclination was unknown. As is common for many long-period exoplanets, the eccentricity is greater than any planets in the Solar System, orbiting at an average distance of 3.28 AU. 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. In 2023, the inclination and true mass of HD 89307 b were determined via astrometry.
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 was one of the smallest extrasolar planets discovered as of 2006.
References
- 1 2 "Keck astronomers discover planets smaller than saturn" (Press release). Kamuela, Hawaii: W. M. Keck Observatory. March 29, 2000. Retrieved August 13, 2019.
- 1 2 Marcy, Geoffrey W.; et al. (2000). "Sub-Saturn Planetary Candidates of HD 16141 and HD 46375". The Astrophysical Journal Letters. 536 (1): L43–L46. arXiv: astro-ph/0004326 . Bibcode:2000ApJ...536L..43M. doi:10.1086/312723. PMID 10849416. S2CID 119530785.
- Butler, R. P.; et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv: astro-ph/0607493 . Bibcode:2006ApJ...646..505B. doi:10.1086/504701. S2CID 119067572.
