• A location in a “safe” place in the galaxy, not close to any active regions, overactive stars, or black holes
  • Being attached to a stable star.  Our sun, a G2 type is ideal
  • Having our host star the proper size, and with proper stable energy output
  • Being in an orbit in the “habitable” zone setting temperature in a fairly narrow region
  • Having several gas giant planets in the system for protection from orbiting debris
  • Having a near-circular orbit assuring that the heat input from the star does not vary much
  • A planet with the proper inclination as it goes around its orbit
  • Having a planet within a certain range of masses
  • Having a planet with a reasonable rotation rate
  • Having an atmosphere with the right composition and density
  • Having liquid water of the proper amount and composition
  • Having a good ratio between water (oceans) and land
  • Having hydrogen with specialized bonding to give water characteristics different than other substances
  • Having a satellite moon of the right size and distance
  • A planet of the proper mass
  • A planet with a liquid iron core to generate a magnetic field
  • A planet with a magnetic field of the proper strength
  • A rocky planet with a crust of the proper thickness to allow plate tectonics to occur
  • A planet with a good source of carbon – in the form to allow chemical reactions
  • A planet with a number of rare element chemicals which are essential to life forms.

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Prerequisites For Life

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Pensamiento Peligroso writes the truth as he sees it, and if it upsets you, then it makes you think!