Goldilocks planet
n. A planet that can support life because it is neither too hot nor too cold, too big nor too small, too near its star nor too far.
Good news for anything living on the Earth-like Goldilocks planet circling Gliese 581 — at a distance of 20.5 light years, there's no chance humans will get there any time soon.
—Larry Highes, “A star trek too far,” The Globe and Mail, April 26, 2007
Last week NASA announced the discovery of a giant gasball of a planet, bigger than Jupiter, 41 light-years from Earth. "Extrasolar" planets are familiar, but this one's orbit is promising. Its wide path hints that its star, 55 Cancri, might also harbor a Goldilocks planet: one whose size, temperature and composition are all just right for life. Current science spots only planets so massive they tug stars into a telltale "wobble." "You could put an Earth around 55 Cancri and we wouldn't know it was there," says Geoff Marcy, a planet hunter at UC, Berkeley.
—Adam Rogers, “Planets for the Finding,” Newsweek, June 24, 2002
1992 (earliest)
With a ceremonial tip of the hat to Christopher Columbus, the space agency next week embarks on a search for new worlds in the sea of interstellar space.

At 3 p.m. Monday, the 500th anniversary of Columbus's landfall in the Americas, NASA will activate two powerful radio telescopes - one in Puerto Rico and one in California - to begin the most comprehensive search ever for other intelligent life in the universe.

Over the next decade, scientists will scan radio emissions from the more than 300 billion stars in the Milky Way galaxy, using sophisticated new computer systems to distinguish the sounds of any intelligent life from the hiss and crackle of natural radio noise in the galaxy.

Not all stars of course, are likely to have planets, especially what researchers call "Goldilocks" planets - not too hot and not too cold for life.
—Mike Toner, “NASA has unveiling set on Columbus Day,” The Atlanta Journal and Constitution, October 10, 1992
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