Galactic Crucibles
Register
Advertisement

The habitable zone is the range where complex, multicellular life can naturally evolve as a result of a liquid solvent existing in all three phases. Life can arise almost anywhere in the universe, but within the habitable zone, the probability of the formation of advanced civilizations is most likely.

Range of liquid water[]

Main sequence[]

  • Class M - 0.02 AU to 0.28 AU
    • M8 - 0.02 to 0.03 (tidal locking, major tidal heating)
    • M7 - 0.03 to 0.05 (tidal locking, major tidal heating)
    • M6 - 0.05 to 0.09 (tidal locking)
    • M5 - 0.08 to 0.11 (tidal locking)
    • M4 - 0.09 to 0.14 (tidal locking)
    • M3 - 0.11 to 0.18
    • M2 - 0.14 to 0.21
    • M1 - 0.17 to 0.24
    • M0 - 0.20 to 0.28
  • Class K - 0.22 AU to 0.77 AU
    • K9 - 0.22 to 0.32
    • K8 - 0.25 to 0.36
    • K7 - 0.27 to 0.40
    • K6 - 0.30 to 0.45
    • K5 - 0.33 to 0.48
    • K4 - 0.35 to 0.51
    • K3 - 0.38 to 0.56
    • K2 - 0.45 to 0.66
    • K1 - 0.49 to 0.72
    • K0 - 0.53 to 0.77
  • Class G - 0.55 AU to 1.35 AU
    • G9 - 0.55 to 0.80
    • G8 - 0.61 to 0.90
    • G7 - 0.64 to 0.94
    • G6 - 0.68 to 1.01
    • G5 - 0.72 to 1.06
    • G4 - 0.76 to 1.11
    • G3 - 0.79 to 1.15
    • G2 - 0.82 to 1.20
    • G1 - 0.87 to 1.27
    • G0 - 0.92 to 1.35
  • Class F - 0.98 AU to 3.06 AU
    • F9 - 0.98 to 1.42
    • F8 - 1.02 to 1.50
    • F7 - 1.12 to 1.64
    • F6 - 1.19 to 1.75
    • F5 - 1.30 to 1.90 (lifetime possibly too short)
    • F4 - 1.38 to 2.03 (lifetime too short)
    • F3 - 1.56 to 2.29 (lifetime too short)
    • F2 - 1.75 to 2.59 (lifetime too short)
    • F1 - 1.93 to 2.86 (lifetime too short)
    • F0 - 2.09 to 3.06 (lifetime too short)

Range of liquid hydrocarbon[]

Range of liquid ammonia[]

Advertisement