HD 81817

Display orbital revolution around the star HD 81817
Imaginary Picture of Star HD 81817
Star Name : HD 81817
Alternate Name :
Star Distance (LY/pc): inf (LY) inf (pc)
Stellar Radius (Rsun): 0.0000 (Rsun, measured) 91.4000 (Rsun, estimated)
Stellar Mass (Msun): 4.3000 (Msun/observed) 4.3000 (Msun/estimated)
Spectral type : K3II-III
Metalicity : -0.1700
Absolute Magnitude : -inf
Apparent Magnitude : 4.40
Right Ascension(RA) : 144.27083
Declination(DEC) : 81.30972
  • This is the HD 81817 . The star HD 81817 islocated about inf light-years ( inf pc) away from our Solar System.
  • The star HD 81817 has apparent magnitude of 4.4, with absolute magnitude of -inf.
  • It is 4.3 times more massive and 91.4 times bigger compared with our Sun. The surface temperature is 4245 with its spectral types of K3II-III
  • Number of Extrasolar Planets : 2
  • Name of the 1 Planet HD 81817 b radius 1.049861 mass 24.128000 orbital distance 3.233000
  • Name of the 2 Planet HD 81817 c radius 1.049861 mass 22.609000 orbital distance 2.325000
    (Illustration of the HD 81817's Planetary System)



    The Star HD 81817 's habitable zone is located at the following distance

    Inner Boundary (the orbital distance at Venus's Equivalent Radiation ) : 35.681 AU ( 5337768044.4 km)
    Earth Boundary (the orbital distance at Earth's Equivalent Radiation) : 49.320 AU ( 7378190362.9 km)
    Outer Boundary (the orbital distance at Mars's Equivalent Radiation) : 75.153 AU ( 11242729323.0 km)
    Snow Line (the orbital distance at Snow Line Equivalent Radiation) : 110.591 AU ( 16544168711.1 km)
    (Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star HD 81817)



    Kopparapu's Recent Venus for Star HD 81817 distance : 39.728 AU
    Kopparapu's Runaway Greenhouse for Earth-sized planet for Star HD 81817 distance : 50.288 AU
    Kopparapu's Runaway Greenhouse for Super-Earth-sized planet for Star HD 81817 distance : 48.571 AU
    Kopparapu's Runaway Greenhouse for Mars-sized planet for Star HD 81817 distance : 53.220 AU
    Kopparapu's Outer Boundary for Maximum Greenhouse for Star HD 81817 distance : 94.287 AU
    Kopparapu's Outer Boundary for Early Mars for Star HD 81817 distance : 99.465 AU
    (Habitable zone calculated based on Kopparapu et al.(2013) around the star HD 81817)



  • Original Kopparapu Recent Venus for Star HD 81817 distance : 39.205 AU
  • Original Kopparapu Runaway Greenhouse for Star HD 81817 distance : 51.961 AU
  • Original Kopparapu Moist Greenhouse for Star HD 81817 distance : 51.875 AU
  • Original Kopparapu Outer Boundary for Maximum Greenhouse for Star HD 81817 distance : 95.808 AU
  • Original Kopparapu Outer Boundary for Early Mars for Star HD 81817 distance : 99.637 AU

    (Habitable zone calculated based on Kopparapu et al.(Original) around the star HD 81817)



    (Position in Stellar Map of star HD 81817 )



    (Zoomed position in Stellar Map of star HD 81817 (zoom level 3))

    (Synthetic Spectrum of star HD 20003*)
    *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