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HD 37124 is a star in the equatorial constellation of Taurus, positioned about a half degree to the SSW of the bright star Zeta Tauri. The apparent visual magnitude of this star is 7.68, which is too dim to be visible to the naked eye. It is located at a distance of 103 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −23 km/s. Three extrasolar planets have been found to orbit the star.
109 Piscium is a yellow hued G-type main-sequence star located about 108 light-years away in the zodiac constellation of Pisces. It is near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.27. The star is moving closer to the Earth with a heliocentric radial velocity of −45.5 km/s. It has one known exoplanet.
HD 175541 is an 8th magnitude star with an exoplanetary companion in the constellation Serpens. It has the proper name Kaveh, which was selected by Iran during the NameExoWorlds campaign as part of the 100th anniversary of the IAU. Kaveh is one of the heroes of Shahnameh. The apparent visual magnitude of 8.02 is too faint for this star to be visible in the naked eye. It is located at a distance of approximately 424 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +20 km/s. Despite its distance, it was given the number 736 in the Gliese Catalogue of Nearby Stars.
HD 185269 is a stellar triple system approximately 170 light-years away in the constellation Cygnus. It is easily visible to binoculars, but not the naked eye.
HD 192699 is a yellow subgiant star located approximately 214 light-years away in the constellation of Aquila. It has the apparent magnitude of 6.45. Based on its mass of 1.68 solar, it was an A-type star when it was a main-sequence. In April 2007, a planet was announced orbiting the star, together with HD 175541 b and HD 210702 b.
HD 210702 is an orange subgiant star located approximately 177 light-years away in the constellation of Pegasus. With a mass of 1.8 times that of the Sun, the star spent its main-sequence life as an A-type star. The visual luminosity is 11.38 times that of the Sun and the magnitude is near the naked-eye limit, but binoculars can easily see it.
Kappa Coronae Borealis, Latinized from κ Coronae Borealis, is a star approximately 98 light years away in the constellation of Corona Borealis. The apparent magnitude is +4.82 and the absolute magnitude is +2.35. It is an orange K-type subgiant star of spectral type K1IV, meaning it has almost completely exhausted its hydrogen supply in its core. It is 1.32 times as massive as the Sun yet has brightened to 11.6 times its luminosity. Around 2.5 billion years old, it was formerly an A-type main sequence star.
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.
Kappa Coronae Borealis b is an extrasolar planet approximately 98 light-years away in the constellation of Corona Borealis. This planet was discovered by Johnson et al., who used the radial velocity method to detect wobbling of the star caused by a planet move around by its tug of gravity. It was first discovered in September 2007 and was published in November.
HD 192699 b, also named Khomsa, is an exoplanet located approximately 214 light-years away in the constellation of Aquila, orbiting the star HD 192699. This planet was discovered in April 2007, massing at least 2.5 times the mass of Jupiter (MJ). Despite its orbital distance more than that of Earth, the orbital period is less than a year, because the parent star is more massive than the Sun.
HD 210702 b is an exoplanet located approximately 177 light-years away in the constellation of Pegasus, orbiting the star HD 210702. This planet, together with HD 175541 b and HD 192699 b, are planets around intermediate mass stars that were announced in April 2007 by Johnson et al. It has at least twice the mass of Jupiter and it orbits with semimajor axis of 1.17 AU, corresponding to a period of 341.1 days.
HD 175541 b, also named Kavian, is a jovian planet located approximately 424 light-years away in the constellation of Serpens, orbiting the star HD 175541. This planet was discovered in April 2007. Despite the distance of planet to star slightly more than Earth to the Sun, the period is less than 300 days that orbits in an eccentric orbit, because the parent star is 65% more massive than the Sun.
HD 185269 b is a hot Jupiter extrasolar planet approximately 170 light years away in the constellation of Cygnus. The minimum mass is slightly less than Jupiter and the orbital period is about one week. Most hot Jupiters are thought to have undergone tidal circularization, making the eccentricity of HD 185269 b (e=0.3) unusual. Despite having a large transit probability, none have yet been detected by various photometric monitoring campaigns.
HD 180902 b is an extrasolar planet orbiting the K-type star HD 180902 approximately 342 light years away in the constellation Sagittarius.
HD 181342 is a star in the constellation of Sagittarius. With an apparent magnitude of 7.55, it cannot be seen with the naked eye. Parallax measurements made by Gaia spacecraft put the star at a distance of 394 light-years away.
HD 163607 b is the innermost planet discovered to orbit a star HD 163607, a star somewhat brighter and older than the Sun. It was discovered using the radial velocity method, and was initially observed as part of the N2K Program. Its minimum mass is at least three quarters of Jupiter's. It follows an eccentric orbit around the host star.
HD 98219, also named Hunahpú, is a subgiant star in the constellation Crater. It has a confirmed exoplanet. At around 4 billion years old, it is a star around 1.3 times as massive as the Sun that has cooled and expanded to 4.5 times the Sun's diameter, brightening to be around 11 times as luminous. The International Astronomical Union (IAU) gave the opportunity to Honduras to name the star Hunahpú as part of NameExoWorlds. Hunahpú was one of the twin gods who became the Sun in K'iche' (Quiché) Mayan mythology.
HD 102956 b or Isagel is an extrasolar planet discovered in 2010 by a team of American astronomers led by John Johnson using Doppler spectroscopy and the Keck Observatory in Hawaii. HD 102956 b is in the orbit of host star HD 102956. The planet is at most the mass of Jupiter, orbiting every 6.5 days at a distance of 12 million km. HD 202956 b has a very circular orbit. The system is roughly 399 light years from us.
HD 108863 is a subgiant star, the primary of a binary star system 540 light-years away, belonging to spectral class K0. Its age is younger than the Sun's at 1.8±0.4 billion years. The primary star is slightly enriched in heavy elements, having 115% of solar abundance. The primary star does not have detectable flare activity.
HD 99706 is an orange-hued star in the northern circumpolar constellation of Ursa Major. With an apparent visual magnitude of 7.65, it is too dim to be visible to the naked eye but can be viewed with a pair of binoculars. Parallax measurements provide a distance estimate of approximately 480 light years from the Sun, and the Doppler shift shows it is drifting closer with a radial velocity of −30 km/s. It has an absolute magnitude of 2.12, indicating it would be visible to the naked eye as a 2nd magnitude star if it were located 10 parsecs away.
References
- 1 2 Giguere, Matthew J.; et al. (2012). "A High-eccentricity Component in the Double-planet System around HD 163607 and a Planet around HD 164509". The Astrophysical Journal. 744 (1): 4–13. arXiv: 1109.2955 . Bibcode: 2012ApJ...744....4G . doi: 10.1088/0004-637X/744/1/4 .
- 1 2 Luhn, Jacob K.; et al. (2019). "Retired A Stars and Their Companions. VIII. 15 New Planetary Signals around Subgiants and Transit Parameters for California Planet Search Planets with Subgiant Hosts". The Astronomical Journal. 157 (4). 149. arXiv: 1811.03043 . Bibcode:2019AJ....157..149L. doi: 10.3847/1538-3881/aaf5d0 .
