Great Regulars: It is, for example, widely assumed

that Earth cannot possibly be the only life-bearing planet in the universe, given how vast the universe is and how many planets there must be. In fact, of 2,326 planets so far spotted by NASA's Kepler space telescope, 10 are said to be about the size of Earth and orbiting their suns in what is called a "habitable zone." Kepler-22b in particular looks promising. Temperature there seems to be around 72 degrees and it circles a star much like our sun.

from Frank Wilson: When Falls the Coliseum: That's What He Said: The presumption that we are not alone

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