Discovery | |
---|---|
Discovery date | 2015 November 17 |
radial velocity method | |
Designations | |
HD 219134 e, HR 8832 h, HR 8832 e | |
Orbital characteristics [1] [2] | |
2.968±0.037 AU | |
Eccentricity | 0.025+0.027 −0.018 |
2100.6±2.9 d [3] | |
2456761±20 JD | |
0.0°±63.0° | |
Semi-amplitude | 5.73+0.22 −0.23 m/s |
Star | HD 219134 |
Physical characteristics [1] [2] | |
Mass | ≥97.9±4.4 M🜨 |
HD 219134 h, also known as HR 8832 h, is an exoplanet orbiting around the K-type star HD 219134 in the constellation of Cassiopeia. It has a minimum mass of 108 Earth masses, which indicates that the planet is likely a gas giant. Unlike HD 219134 b and c it is not observed to transit and thus its radius and density are unknown.
This planet was initially reported in two 2015 papers; one referred to it as HD 219134 e, [4] while the other found different, and more accurate, parameters for it and so treated it as a different planet, designated HD 219134 h. [5] It is now generally referred to by the HD 219134 h designation. [6] [2]
HD 219134 is a main-sequence star in the constellation of Cassiopeia. It is smaller and less luminous than the Sun, with a spectral class of K3V, which makes it an orange-hued star. HD 219134 is relatively close to our system, with an estimated distance of 21.34 light years. This star is close to the limit of apparent magnitude that can still be seen by the unaided eye. The limit is considered to be magnitude 6 for most observers. This star has a magnitude 9.4 optical companion at an angular separation of 106.6 arcseconds.
HD 20782 is the primary of a wide binary system located in the southern constellation Fornax. It has an apparent magnitude of 7.38, making it readily visible in binoculars but not to the naked eye. The system is located relatively close at a distance of 117 light-years based on Gaia DR3 parallax measurements, but it is receding with a heliocentric radial velocity of 40.7 km/s. At its current distance, HD 20782's brightness is diminished by 0.12 magnitudes due to interstellar extinction and it has an absolute magnitude of +4.61.
The Hungarian Automated Telescope Network (HATNet) project is a network of six small fully automated "HAT" telescopes. The scientific goal of the project is to detect and characterize extrasolar planets using the transit method. This network is used also to find and follow bright variable stars. The network is maintained by the Center for Astrophysics | Harvard & Smithsonian.
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.
WASP-11/HAT-P-10 is a binary star. It is a primary main-sequence orange dwarf star. Secondary is M-dwarf with a projected separation of 42 AU. The system is located about 424 light-years away in the constellation Aries.
HD 88133 b is an extrasolar planet orbiting the star HD 88133. It is probably less massive than Jupiter and even Saturn. It orbits the star in a very tight orbit, completing one revolution around the star in every three and half days or so. Despite the relatively large radius of the star, no transits have been detected.
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 219134 g, also known as HR 8832 g, is an unconfirmed exoplanet orbiting around the K-type star HD 219134 in the constellation of Cassiopeia. It has a minimum mass of 11 or 15 Earth masses, suggesting that it is likely a Neptune-like ice giant. Unlike HD 219134 b and HD 219134 c it is not observed to transit and thus its radius and density are unknown. If it has an Earth-like composition, it would have a radius 1.9 times that of Earth. However, since it is probably a Neptune-like planet, it is likely larger.
GJ 3470 b is an exoplanet orbiting the star GJ 3470, located in the constellation Cancer. With a mass of just under 14 Earth-masses and a radius approximately 4.3 times that of Earth's, it is likely something akin to Neptune despite the initially strong belief that the planet was not covered in clouds like the gas giants in the Solar System.
HAT-P-18 is a K-type main-sequence star about 530 light-years away. The star is very old and has a concentration of heavy elements similar to solar abundance. A survey in 2015 detected very strong starspot activity on HAT-P-18.
HAT-P-15 is a G-type main-sequence star about 630 light-years away. The star is older than Sun yet has a concentration of heavy elements roughly 190% of solar abundance. The star has no noticeable starspot activity.
HD 116029 is a binary star system about 400 light-years away.
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.