Imaginary Picture of K2-228 b

Display orbital revolution of K2-228 b around the hoststar K2-228
/
Exoplanet Name : K2-228 b
Alternate Name : "2MASS J12291074-0650033 b, EPIC 228798746 b, EPIC 228798746.01, WISE J122910.73-065003.2 b"
Status : Confirmed
Radius (Rjup / Re): 0.1080 (Rjup) 1.2106 (Rearth)
Mass (Mjup / Me): 0.0061 (Mjup) 1.9471 (Mearth)
Semi Major Axis / Orbital Distance Calculated 0.0338 (AU) 0.0338 (AU Est.)
Eccentricity : 0.0000
Orbital Period(Yrs) 0.0074
Orbital Period(Observed/Estimated) 2.70 (Days Obs.) 2.69 (Days Est.)
Surface Gravity (G Earth) 1.3287
Star Radiation at Atmospheric Boundary: 224142.9 (W/m2)
Measured Temperature (K) 0.0 (K)
Blackbody T 0.1(K) 971.1 (K)
Blackbody T 0.3(K) 912.0 (K)
Blackbody T 0.7(K) 737.9 (K)
Tidally Locked Blackbody T 0.1(K) 1154.9 (K)
Tidally Locked Blackbody T 0.3(K) 1084.5 (K)
Size Class: super-Earth-size
Mass Class:
Detection Type : Primary Transit
Mass Detection :
Radius Detection :
Habitability by Solar Eq. Astronomical Unit: Not habitable
Habitability by Kopparapu: Not habitable
Star Name : K2-228
Alternate Name : "2MASS J12291074-0650033, EPIC 228798746, WISE J122910.73-065003.2"
Star Distance(LY) : 529.2
Stellar Radius(Rsun) : 0.7 (Rsun Measured)
Stellar Mass(Msun) : 0.7 (Msun Measured) 0.7 (Msun Estimated)
Star Age : 0.0 (GY)
Temperature : 4715 (K)
Spectral type : K3
UV portion[%]: 2.2
Visible portion[%]: 34.4
IR portion[%]: 63.4
Metalicity : -0.2
Absolute Magnitude: 4.9
Apparent Magnitude: 11.0
Right Ascension(RA) 187.2948
Declination (DEC) -6.8343
Hubble Space Telescope Guide Star Catalog (GSC) ID
Discovered by
Discovery Paper - Authors
Discovery Paper - Title
Discovery Paper - Journal
Discovery Paper - URL
SIMBAD LINK http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=K2-228+&submit=SIMBAD+search
Open Exoplanet Database Link
K2-228 b
K2-228 b

  • K2-228 b is an exoplanet orbiting the star K2-228, located about 529.2 light-years (162.3 pc) away from Solar System. Its discovery was publicly announced on 2018.
  • The host star K2-228 has apparent magnitude of 11.0, with absolute magnitude of 4.9.
  • It is 0.7 times more massive and 0.7 times bigger compared with our Sun. The surface temperature is 4715 with its spectral types of K3
  • In this planetary system, the extrasolar planet K2-228 b orbits around the star K2-228 every 2.7 days with its orbital distance of 0.03 AU ( 5056408.0 km)
  • (Projected orbit of K2-228 b around its host star K2-228)


  • The Star K2-228 's habitable zone is located at the following distance
  • Inner Boundary (the orbital distance at Venus's Equivalent Radiation ) : 0.313 AU ( 46831154.4 km)
  • Earth Boundary (the orbital distance at Earth's Equivalent Radiation) : 0.433 AU ( 64732893.8 km)
  • Outer Boundary (the orbital distance at Mars's Equivalent Radiation) : 0.659 AU ( 98638604.8 km)
  • Snow Line (the orbital distance at Snow Line Equivalent Radiation) : 0.970 AU ( 145151028.0 km)
  • Radiation at Planetary Boundary of K2-228 b : 224142.86 W/m2

    (Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star K2-228)



  • Kopparapu Recent Venus for Star K2-228 distance : 0.343 AU
  • Kopparapu Runaway Greenhouse for Earth-sized planet for Star K2-228 distance : 0.434 AU
  • Kopparapu Runaway Greenhouse for Super-Earth-sized planet for Star K2-228 distance : 0.419 AU
  • Kopparapu Runaway Greenhouse for Mars-sized planet for Star K2-228 distance : 0.460 AU
  • Kopparapu Outer Boundary for Maximum Greenhouse for Star K2-228 distance : 0.796 AU
  • Kopparapu Outer Boundary for Early Mars for Star K2-228 distance : 0.840 AU

    (Habitable zone calculated based on Kopparapu et al.(2013) around the star K2-228)



  • Original Kopparapu Recent Venus for Star K2-228 distance : 0.339 AU
  • Original Kopparapu Runaway Greenhouse for Star K2-228 distance : 0.448 AU
  • Original Kopparapu Moist Greenhouse for Star K2-228 distance : 0.448 AU
  • Original Kopparapu Outer Boundary for Maximum Greenhouse for Star K2-228 distance : 0.810 AU
  • Original Kopparapu Outer Boundary for Early Mars for Star K2-228 distance : 0.842 AU

    (Habitable zone calculated based on Kopparapu et al.(Original) around the star K2-228)



    (Position in Stellar Map of star K2-228 and its Exoplanet K2-228 b)



    (Zoomed position in Stellar Map of star K2-228 and its Exoplanet K2-228 b (zoom level 3))

    (Synthetic Spectrum of star K2-228*)
    *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