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HD 12661 is a G-type main sequence star in the northern constellation of Aries. The star is slightly larger and more massive than the Sun, with an estimated age of seven billion years. It has two known extrasolar planets.
HD 74156 is a yellow dwarf star in the constellation of Hydra, 187 light years from the Solar System. It is known to be orbited by two giant planets.
HD 187123 is a single, yellow-hued star with two exoplanetary companions in the northern constellation of Cygnus. It has an apparent visual magnitude of 7.83, making it an 8th magnitude star that is too faint to be visible with the naked eye. However, it should be easy target with binoculars or small telescope. The system is located at a distance of 150 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −17 km/s.
HD 217107 is a yellow subgiant star approximately 65 light-years away from Earth in the constellation of Pisces. Its mass is very similar to the Sun's, although it is considerably older. Two planets have been discovered orbiting the star: one is extremely close and completes an orbit every seven days, while the other is much more distant, taking fourteen years to complete an orbit.
Gliese 777, often abbreviated as Gl 777 or GJ 777, is a yellow subgiant approximately 52 light-years away in the constellation of Cygnus. The system is also a binary star system made up of two stars and possibly a third. As of 2005, two extrasolar planets are known to orbit the primary star.
HD 108874 is a yellow dwarf star in the constellation of Coma Berenices. It is 195 light years from Earth and has two extrasolar planets that are possibly in a 9:2 orbital resonance.
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 217107 c is an extrasolar planet approximately 64 light-years away from Earth in the constellation of Pisces. The planet was the second planet to be discovered orbiting the star HD 217107. HD 217107 c's existence was hypothesized in 1998 due to the eccentricity of the inner planet's orbit and confirmed in 2005 when radial velocity studies of the star indicated another, more distant and massive companion orbiting the star. The planet has an eccentric orbit lasting on order of a decade.
HD 66428 is a G-type main sequence star located approximately 174 light-years away in the constellation of Monoceros. This star is similar to the Sun with an apparent magnitude of 8.25, an effective temperature of 5705 ± 27 K and a solar luminosity 1.28. Its absolute magnitude is 11.1 while its U-V color index is 0.71. It is considered an inactive star and it is metal-rich . This star has a precise mass of 1.14552 solar masses. This precision comes from the Corot mission that measured asteroseismology.
HD 11964 is a binary star system located 110 light-years away from the Sun in the equatorial constellation of Cetus. It is visible in binoculars or a telescope but is too faint to be seen with the naked eye, having an apparent visual magnitude of 7.51. The system is drifting closer to the Sun with a radial velocity of −9 km/s. Two extrasolar planets have been confirmed to orbit the primary.
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.
Gliese 777 c, often catalogued as Gliese 777 Ac or simply HD 190360 c, 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 2005 using the radial velocity method and confirmed in 2009. The planet was once called the "smallest extrasolar planet discovered", but this is currently no longer the case. With a minimum mass just 18 times that of the Earth, the planet is likely a "hot Neptune" planet, a small Jovian planet, or possibly a large terrestrial planet.
HD 183263 is an 8th magnitude subgiant star located approximately 177 light-years away in the constellation Aquila. This star is about to or already ran out of hydrogen fuel at its core and is evolving into a red giant before dying as a white dwarf. It has absolute magnitude of 4.16 compared to the Sun’s 4.83, which indicates the star is more luminous than the Sun, and therefore hotter by about 100 K.
HD 8673 is a binary star in the northern constellation of Andromeda. It has an apparent magnitude and absolute magnitude of 6.34 and 3.56 respectively. Based upon an annual parallax shift of 26.2 mas, the system is located around 124.5 light years away. The system is moving further from the Earth with a heliocentric radial velocity of +19 km/s. A sub-stellar companion was detected in 2005; it could either be an exoplanet or a brown dwarf.
HD 187123 b is a typical "hot Jupiter" located approximately 150 light-years away in the constellation of Cygnus, orbiting the star HD 187123. It has a mass about half that of Jupiter and it orbits in a very tight, round orbit around the star every three days.
HD 187123 c is an extrasolar planet located approximately 156 light-years away in the constellation of Cygnus, orbiting the star HD 187123. This planet was published in 2006. The radius of the planet's orbit is 4.80 AU, 113 times more distant from the star than first companion. This takes 10 years to orbit. As it is typical for very long-period planets, the orbit is eccentric, referring to as "eccentric Jupiter". At periastron, the orbital distance is 3.60 AU and at apastron, the distance is 6.00 AU. The planet's mass is nearly 2 times that of Jupiter, but is likely to be smaller in size than the inner planet.
HD 183263 b is an extrasolar planet orbiting the star HD 183263. This planet has a minimum mass of 3.6 times more than Jupiter and takes 625 days to orbit the star. The planet was discovered on January 25, 2005 using multiple Doppler measurements of five nearby FGK main-sequence stars and subgiants obtained during the past 4–6 years at the Keck Observatory in Mauna Kea, Hawaii. These stars, namely, HD 183263, HD 117207, HD 188015, HD 45350, and HD 99492, all exhibit coherent variations in their Doppler shifts consistent with a planet in Keplerian motion, and the results were published in a paper by Geoffrey Marcy et al. Photometric observations were acquired for four of the five host stars with an automatic telescope at Fairborn Observatory. The lack of brightness variations in phase with the radial velocities supports planetary-reflex motion as the cause of the velocity variations. An additional planet in the system was discovered later.
HD 108874 b is a gas giant announced in 2003. The orbit lies in the star's habitable zone. It is expected that any moons orbiting this planet are enriched in carbon, and are thus quite different from the silicate-rich bodies in the Solar System. The planet is possibly in a 4 : 1 orbital resonance with HD 108874 c.
HD 108874 c is a gas giant discovered in 2005 which orbits beyond the star's habitable zone, and receives insolation 15.9% that of Earth. It has minimum mass similar to Jupiter, although since the inclination of the orbit is not known the true mass of this planet could be much greater. The planet is possibly in a 4 : 1 orbital resonance with HD 108874 b.
References
- 1 2 Wright, J. T.; et al. (2009). "Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems". The Astrophysical Journal. 693 (2): 1084–1099. arXiv: 0812.1582 . Bibcode:2009ApJ...693.1084W. doi:10.1088/0004-637X/693/2/1084.
- 1 2 3 4 5 Feng, Y. Katherina; et al. (2015). "The California Planet Survey IV: A Planet Orbiting the Giant Star HD 145934 and Updates to Seven Systems with Long-period Planets". The Astrophysical Journal. 800 (1). 22. arXiv: 1501.00633 . Bibcode:2015ApJ...800...22F. doi:10.1088/0004-637X/800/1/22.
- ↑ Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series . 262 (21). arXiv: 2208.12720 . Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57.
