HD 114762 b

Not to be confused with HD 114762 b's stellar companion, HD 114762.
HD 114762 b[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Coma Berenices
Right ascension 13h 12m 19.7428s[2]
Declination +17° 31′ 01.654″[2]
Astrometry
Distance126±2[2] ly
(38.6±0.7[2] pc)
Orbit
PrimaryHD 114762
Period (P)83.915±0.003 d[3]
Semi-major axis (a)0.375±0.006 AU[3]
Eccentricity (e)0.566+0.012
−0.011[3]
Inclination (i)6.23+1.97
−1.26[3]°
Periastron epoch (T)2449889.106±0.186[4]
Argument of periastron (ω)
(secondary)		201.3±1.0[3]°
Semi-amplitude (K2)
(secondary)		612.48±3.52[4] km/s
Details
Mass107+20
−27[3] 147.0+39.3
−42.0[5] MJup
Database references
SIMBADdata

HD 114762 b is a small red dwarf star, in the HD 114762 system,[3] formerly thought to be a massive gaseous[6][7] extrasolar planet,[8] approximately 126 light-years (38.6 pc) away in the constellation of Coma Berenices.[1][6] This optically undetected companion to the late F-type main-sequence star HD 114762 was discovered in 1989 by Latham, et al.,[7] and confirmed in an October 1991 paper by Cochran, et al.[9] It was thought to be the first discovered exoplanet (although its existence was confirmed after those around PSR B1257+12.)

The object orbits the primary star every 83.9 days at an approximate distance of 0.37 AU,[3] with an orbital eccentricity of 0.57;[3] for comparison, this orbit is similar to that of Mercury but with almost three times the eccentricity.[3] Based on the radial velocity measurements alone, it was estimated to have a minimum mass of 11.069±0.063  MJ (at 90°)[10] and a probable mass of approximately 63.2 MJ (at 10°).[11] However, analysis of its astrometric perturbation of its host star in 2019 found it to have an extremely low inclination of only 6.23+1.97
−1.26 degrees, giving it a true mass of 107+20
−27 MJ and putting it well outside of the range of planetary masses (less than 13 MJ).[3]

HD 114762 b was thought for a time to be the first extrasolar planet ever detected, predating the 1992 pulsar planets found around PSR B1257+12 and main-sequence yellow dwarf 51 Pegasi.[12][13] However, now that it has been found to not be a planet, the planets found orbiting PSR B1257+12 were indeed the first exoplanets ever found.[3]

At an event celebrating the career of discoverer David Latham and attended by his colleagues and collaborators, the object was informally dubbed "Latham's Planet".[14] However, this name has no official standing with the International Astronomical Union.

  1. ^ a b Cite error: The named reference Butler2006 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Gaia2016 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h i j k l Cite error: The named reference Kiefer2019 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Kane2011 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Kiefer2020 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference North2003 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Latham1989 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference simbad was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Cochran1991 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference wang was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Kane2012 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Hale1995 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Marcy1999 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Johnson2016 was invoked but never defined (see the help page).