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Most of the planets of the stars. Stars similar to our sun. Planets similar to the earth. Planets with proper conditions.
has different laws has one common law shares the same laws shares no common law
it is impossible for life to exist on planets earthlike life could only exist on a few planets life could exist on only one planet in a million life could exist on a great number of planets
carrying passengers to planets acting as stop- over points refueling spacecraft providing supply of air, food and water
The planet must be as big and heavy as the earth. Proper conditions are essential to the existence of life. Double stars can provide steady light and heat. The distance between a planet and its sun should be right.
the right amount of atmosphere our own solar system steady heat and light the right distance from the sun
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