All articles starting with H
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HD 193793
HD 193793, better known as WR 140, is a massive Wolf-Rayet and O5 binary star in Cygnus, the prototype of colliding-wind binaries that make dust every 7.9 years.
HD 19445
HD 19445 is a metal-poor F-type subdwarf in Perseus, an ancient Population II halo star about 40 parsecs away, one of the first stars shown to be metal-deficient.
HD 195019
HD 195019 is a G-type star about 123 light-years from the Sun, in a binary system, hosting the gas giant HD 195019 b found in 1998.
HD 196050
HD 196050 is a metal-rich G3 V star with the gas giant HD 196050 b (4.7 Jupiter masses, 1392-day orbit at 2.65 au, e=0.20), found by radial velocity in 2002, plus two M-dwarf companions Ba and Bb about 500 au away.
HD 196067
HD 196067 is a metal-rich G-type star about 40 pc away in Octans, primary of a wide binary with HD 196068. It hosts super-Jupiter HD 196067 b (11.4 Mjup, 3414-day orbit) and Neptune-like HD 196067 c (10.4 Earth masses, 4.6-day period, found 2025).
HD 199579
HD 199579 is a spectroscopic binary star in the constellation Cygnus about 870 light years away, consisting of an O6.5V primary and a B-type companion in a 48.5-day orbit.
HD 20003
HD 20003 (HIP 14530) is a G8 V star 41.8 parsecs away in Hydrus with two Neptune-mass planets, HD 20003 b (11.66 Earth masses, 11.85-day orbit) and HD 20003 c (14.44 Earth masses, 33.92-day orbit), found by HARPS radial velocity measurements.
HD 200775
HD 200775, also cataloged as MWC 361, is a young, massive Herbig Be star in Cepheus that illuminates the reflection nebula NGC 7023, the Iris Nebula.
HD 200964
HD 200964 is a G-type subgiant about 223 light-years away with two gas giants, HD 200964 b and c, found by radial velocity in 2010 and locked near a 4:3 mean motion resonance.
HD 201891
HD 201891, also cataloged as HIP 104659, is a metal-poor G-type dwarf star in Equuleus about 33.5 parsecs from the Sun, roughly 10 billion years old and a long-serving spectroscopic standard.
HD 202206
HD 202206 is a G6V star about 46 pc away with two substellar companions in a rare 5:1 mean-motion resonance; the inner one (HD 202206 b) is near the brown-dwarf limit, and the system may be a circumbinary G+M binary.
HD 202696
HD 202696 (HIP 105056) is a K-type giant star 188.5 pc away with two confirmed Jovian-mass planets, HD 202696 b and c, found by radial velocity in 2019 near an 11:6 resonance.
HD 202772 A
HD 202772 A is an evolved F-type star about 161.5 pc away, primary of a wide binary with HD 202772 B. Its hot Jupiter HD 202772 A b, the first TESS-confirmed hot Jupiter, orbits in 3.3 days and is the most irradiated hot Jupiter known in a wide binary.
HD 203030
HD 203030 is a slightly cool solar analog star about 128 light-years away, best known for its directly imaged young L dwarf companion HD 203030B.
HD 203387
HD 203387 (iota Capricorni, 32 Cap, HIP 105515, HR 8167) is an evolved giant star 61.7 parsecs away in Capricornus with two confirmed gas giant planets, HD 203387 b (3.48 Jupiter masses) and c (7.485 Jupiter masses), found by radial velocity in 2022.
HD 2039
HD 2039 is a metal-rich G2/G3 IV-V star about 86 parsecs away in Phoenix; its planet HD 2039 b, a 6.29-Jupiter-mass gas giant in an eccentric 1120-day, 2.2 AU orbit, was found by radial velocity in 2002 (Tinney et al. 2003).
HD 204313
HD 204313 is a metal-rich G5V star about 48 pc away hosting at least three radial-velocity planets: Neptune-mass HD 204313 c (35 d), giant HD 204313 b (4.6 Mjup, 5.6 yr), and super-Jovian HD 204313 e.
HD 204827
HD 204827 is a heavily reddened, multiple O-type star in Cepheus whose 2008 spectrum survey cataloged 380 diffuse interstellar bands, making it a standard reference sightline for that field.
HD 206267
HD 206267 is a massive multiple star system at the center of the nebula IC 1396 in Cepheus, ionizing the Elephant's Trunk Nebula from about 2,400 light-years away.
HD 206893
HD 206893 is a nearby F5V star, located 38 parsecs from Earth, that hosts a debris disk and two confirmed substellar companions: a red brown dwarf and a planet.
HD 207832
HD 207832 is a G5 V star 58.9 parsecs away hosting two gas giants, HD 207832 b (0.56 Jupiter masses, 162-day orbit) and c (0.73 Jupiter masses, 1156-day orbit), found in 2012 by Keck/HIRES radial velocity in the Lick-Carnegie Survey.
HD 207897
HD 207897 (TOI-1611) is a nearby, bright K0V star 28 pc away hosting HD 207897 b, a dense transiting sub-Neptune of 14-16 Earth masses in a 16.2-day orbit, discovered with TESS and SOPHIE, APF, and HIRES radial velocities.
HD 20794
HD 20794 is a nearby (6.04 pc) naked-eye G-type star with a radial-velocity planetary system; its eccentric 647-day super-Earth (HD 20794 d/f) crosses the habitable zone, while planet c was refuted in 2025.
HD 208487
HD 208487 (Itonda) is a nearby Sun-like star 45 parsecs away in Grus with the confirmed gas giant HD 208487 b (Mintome), a 0.46-Jupiter-mass planet on a 129.36-day, eccentric 0.53-AU orbit found by radial velocity in 2004, plus two 2025 candidate planets.
HD 209458
HD 209458 is a Sun-like star about 153 light-years from Earth in the constellation Pegasus, whose giant planet gave the first observed exoplanet transit in November 1999.
HD 210277
HD 210277 is a G8V dwarf star 21.3 parsecs away with one confirmed planet, HD 210277 b, a 1.29-Jupiter-mass gas giant in an eccentric 442-day orbit at 1.13 AU, found by radial velocity in 1998.
HD 212301
HD 212301 is an F-type star about 180 light years away in the constellation Octans that hosts HD 212301 b, a gas giant found by radial velocity in 2005.
HD 213240
HD 213240 is a bright G/F-type star about 40.9 pc away in Grus, hosting the 2001 radial-velocity gas giant HD 213240 b (5.21 Jupiter masses, 882.7-day eccentric orbit) and a wide M-dwarf companion, HD 213240 C.
HD 213885
HD 213885 (TOI-141) is a bright G-type star 48 parsecs away hosting HD 213885 b, a 1.008-day ultra-short-period iron-enriched super-Earth found by TESS, and HD 213885 c, a non-transiting Neptune-mass planet in a 4.79-day orbit.
HD 214419
HD 214419, also cataloged as CQ Cephei and WR 155, is a Wolf-Rayet binary star in Cepheus whose WN6 star orbits an O companion every 1.64 days.