Imaginary Picture of Barnard's b
/
Exoplanet Name : Barnard's b
Alternate Name : GJ 699 b
Radius (Rjup / Re): 0.1219 (Rjup) 1.3662 (Rearth)
Mass (Mjup / Me): 0.0102 (Mjup) 3.2303 (Mearth)
Semi Major Axis / Orbital Distance Calculated 0.0000 (AU) 0.4046 (AU Est.)
Eccentricity : 0.3200
Orbital Period(Yrs) 0.6374
Orbital Period(Observed/Estimated) 232.80 (Days Obs.) 0.00 (Days Est.)
Star Radiation at Atmospheric Boundary: 27.4 (W/m2)
Measured Temperature (K) 0.0 (K)
Blackbody T 0.1(K) 102.1 (K)
Blackbody T 0.3(K) 95.9 (K)
Blackbody T 0.7(K) 77.6 (K)
Tidally Locked Blackbody T 0.1(K) 121.4 (K)
Tidally Locked Blackbody T 0.3(K) 114.0 (K)
Size Class: super-Earth-size
Mass Class:
Detection Type : Radial Velocity
Mass Detection : Radial Velocity
Radius Detection :
Habitability by Solar Eq. Astronomical Unit: Not habitable
Habitability by Kopparapu: Not habitable
Star Name : Barnard's star
Alternate Name : GJ 699
Star Distance(LY) : 6.0
Stellar Radius(Rsun) : 0.2 (Rsun Measured)
Stellar Mass(Msun) : 0.2 (Msun Measured) 0.2 (Msun Estimated)
Star Age : 8.5 (GY)
Temperature : 3278 (K)
Spectral type : M4V
Metalicity : 0.0
Absolute Magnitude: 13.2
Apparent Magnitude: 9.5
Right Ascension(RA) 269.4521
Declination (DEC) 4.6933
Hubble Space Telescope Guide Star Catalog (GSC) ID 00425-00184
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=Barnard%27s+star&submit=SIMBAD+search
Open Exoplanet Database Link
Barnard's b
Barnard's b

  • Barnard's b is an exoplanet orbiting the star Barnard's star, located about 6.0 light-years ( 1.8 pc) away from Solar System. Its discovery was publicly announced on 2018.
  • The host star Barnard's star has apparent magnitude of 9.5, with absolute magnitude of 13.2.
  • It is 0.2 times more massive and 0.2 times bigger compared with our Sun. The surface temperature is 3278 with its spectral types of M4V
  • In this planetary system, the extrasolar planet Barnard's b orbits around the star Barnard's star every 232.8 days with its orbital distance of 0.40 AU ( 60522442.7 km)
  • (Projected orbit of Barnard's b around its host star Barnard's star)


  • The Star Barnard's star 's habitable zone is located at the following distance
  • Inner Boundary (the orbital distance at Venus's Equivalent Radiation ) : 0.041 AU ( 6198634.3 km)
  • Earth Boundary (the orbital distance at Earth's Equivalent Radiation) : 0.057 AU ( 8568132.5 km)
  • Outer Boundary (the orbital distance at Mars's Equivalent Radiation) : 0.087 AU ( 13055937.7 km)
  • Snow Line (the orbital distance at Snow Line Equivalent Radiation) : 0.128 AU ( 19212384.3 km)
  • Radiation at Planetary Boundary of Barnard's b : 27.41 W/m2

    (Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star Barnard's star)



  • Kopparapu Recent Venus for Star Barnard's star distance : 0.047 AU
  • Kopparapu Runaway Greenhouse for Earth-sized planet for Star Barnard's star distance : 0.059 AU
  • Kopparapu Runaway Greenhouse for Super-Earth-sized planet for Star Barnard's star distance : 0.057 AU
  • Kopparapu Runaway Greenhouse for Mars-sized planet for Star Barnard's star distance : 0.063 AU
  • Kopparapu Outer Boundary for Maximum Greenhouse for Star Barnard's star distance : 0.117 AU
  • Kopparapu Outer Boundary for Early Mars for Star Barnard's star distance : 0.123 AU

    (Habitable zone calculated based on Kopparapu et al.(2013) around the star Barnard's star)



  • Original Kopparapu Recent Venus for Star Barnard's star distance : 0.047 AU
  • Original Kopparapu Runaway Greenhouse for Star Barnard's star distance : 0.062 AU
  • Original Kopparapu Moist Greenhouse for Star Barnard's star distance : 0.062 AU
  • Original Kopparapu Outer Boundary for Maximum Greenhouse for Star Barnard's star distance : 0.119 AU
  • Original Kopparapu Outer Boundary for Early Mars for Star Barnard's star distance : 0.123 AU

    (Habitable zone calculated based on Kopparapu et al.(Original) around the star Barnard's star)



    (Position in Stellar Map of star Barnard's star and its Exoplanet Barnard's b)



    (Zoomed position in Stellar Map of star Barnard's star and its Exoplanet Barnard's b (zoom level 3))