Imaginary Picture of HD 22781 b

Display orbital revolution of HD 22781 b around the hoststar HD 22781
/
Exoplanet Name : HD 22781 b
Alternate Name :
Status : Confirmed
Radius (Rjup / Re): 0.9078 (Rjup) 10.1759 (Rearth)
Mass (Mjup / Me): 13.6500 (Mjup) 4339.8537 (Mearth)
Semi Major Axis / Orbital Distance Calculated 1.1670 (AU) 1.1670 (AU Est.)
Eccentricity : 0.8191
Orbital Period(Yrs) 1.4457
Orbital Period(Observed/Estimated) 528.07 (Days Obs.) 531.70 (Days Est.)
Surface Gravity (G Earth) 41.9114
Star Radiation at Atmospheric Boundary: 239.4 (W/m2)
Measured Temperature (K) 0.0 (K)
Blackbody T 0.1(K) 175.6 (K)
Blackbody T 0.3(K) 164.9 (K)
Blackbody T 0.7(K) 133.4 (K)
Tidally Locked Blackbody T 0.1(K) 208.8 (K)
Tidally Locked Blackbody T 0.3(K) 196.1 (K)
Size Class: Jupiter-size
Mass Class:
Detection Type : Radial Velocity
Mass Detection :
Radius Detection :
Habitability by Solar Eq. Astronomical Unit: Not habitable
Habitability by Kopparapu: Not habitable
Star Name : HD 22781
Alternate Name :
Star Distance(LY) : 102.5
Stellar Radius(Rsun) : 0.6 (Rsun Estimated)
Stellar Mass(Msun) : 0.8 (Msun Measured) 0.8 (Msun Estimated)
Star Age : 4.8 (GY)
Temperature : 5027 (K)
Spectral type : K0V
UV portion[%]: 3.4
Visible portion[%]: 37.4
IR portion[%]: 59.2
Metalicity : -0.4
Absolute Magnitude: 6.3
Apparent Magnitude: 8.8
Right Ascension(RA) 55.2064
Declination (DEC) 31.8264
Hubble Space Telescope Guide Star Catalog (GSC) ID 02355-00246
Discovered by
Discovery Paper - Authors 0
Discovery Paper - Title
Discovery Paper - Journal 0
Discovery Paper - URL 0
SIMBAD LINK http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+22781+&submit=SIMBAD+search
Open Exoplanet Database Link http://www.openexoplanetcatalogue.com/planet/HD%2022781%20b/
HD 22781 b
HD 22781 b

  • HD 22781 b is an exoplanet orbiting the star HD 22781, located about 102.5 light-years (31.4 pc) away from Solar System. Its discovery was publicly announced on 2011.
  • The host star HD 22781 has apparent magnitude of 8.8, with absolute magnitude of 6.3.
  • It is 0.8 times more massive and 0.6 times bigger compared with our Sun. The surface temperature is 5027 with its spectral types of K0V
  • In this planetary system, the extrasolar planet HD 22781 b orbits around the star HD 22781 every 528.1 days with its orbital distance of 1.17 AU ( 174580715.1 km)
  • (Projected orbit of HD 22781 b around its host star HD 22781)


  • The Star HD 22781 's habitable zone is located at the following distance
  • Inner Boundary (the orbital distance at Venus's Equivalent Radiation ) : 0.353 AU ( 52842615.1 km)
  • Earth Boundary (the orbital distance at Earth's Equivalent Radiation) : 0.488 AU ( 73042303.4 km)
  • Outer Boundary (the orbital distance at Mars's Equivalent Radiation) : 0.744 AU ( 111300306.2 km)
  • Snow Line (the orbital distance at Snow Line Equivalent Radiation) : 1.095 AU ( 163783276.3 km)
  • Radiation at Planetary Boundary of HD 22781 b : 239.40 W/m2

    (Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star HD 22781)



  • Kopparapu Recent Venus for Star HD 22781 distance : 0.382 AU
  • Kopparapu Runaway Greenhouse for Earth-sized planet for Star HD 22781 distance : 0.483 AU
  • Kopparapu Runaway Greenhouse for Super-Earth-sized planet for Star HD 22781 distance : 0.467 AU
  • Kopparapu Runaway Greenhouse for Mars-sized planet for Star HD 22781 distance : 0.512 AU
  • Kopparapu Outer Boundary for Maximum Greenhouse for Star HD 22781 distance : 0.875 AU
  • Kopparapu Outer Boundary for Early Mars for Star HD 22781 distance : 0.923 AU

    (Habitable zone calculated based on Kopparapu et al.(2013) around the star HD 22781)



  • Original Kopparapu Recent Venus for Star HD 22781 distance : 0.378 AU
  • Original Kopparapu Runaway Greenhouse for Star HD 22781 distance : 0.498 AU
  • Original Kopparapu Moist Greenhouse for Star HD 22781 distance : 0.500 AU
  • Original Kopparapu Outer Boundary for Maximum Greenhouse for Star HD 22781 distance : 0.890 AU
  • Original Kopparapu Outer Boundary for Early Mars for Star HD 22781 distance : 0.925 AU

    (Habitable zone calculated based on Kopparapu et al.(Original) around the star HD 22781)



    (Position in Stellar Map of star HD 22781 and its Exoplanet HD 22781 b)



    (Zoomed position in Stellar Map of star HD 22781 and its Exoplanet HD 22781 b (zoom level 3))

    (Synthetic Spectrum of star HD 22781*)
    *Yamashiki YA et al. 2019 ApJ 881 114
    MUSCLES Paper I - France et al. 2016 ApJ 820 89
    MUSCLES Paper II- Youngblood et al. 2016 ApJ 824 101
    MUSCLES Paper III- Loyd et al. 2016 ApJ 824 102