What if you found a twin you suspected might exist, though you had no proof? What if you set out to find this twin and learned that someone in another place might be that long-lost sibling? A mixture of fear, curiosity, and excitement might prompt you to set up a fateful meeting.

Scientists at NASA think they have found something like a twin for Earth. Thanks to the Kepler telescope, launched on a planet-hunting mission in 2009, they have discovered a planet that is sufficiently like Earth that it could be hospitable to life, even intelligent life.

The new planet, unpoetically called Kepler-22b, is in a place known by a poetic metaphor -- the Goldilocks zone, where the porridge of life is not too hot and not too cold. Its surface temperature is a pleasant 72 degrees. It revolves around a star that could be our sun's twin, a year there being 290 days.

The only problem is that this planet is 2.4 times the size of Earth, and scientists fear it may be covered with gas or liquid. Our twin could be all wet.

Unfortunately, no family reunion is likely. Kepler-22b is 600 light years away. But absence makes the heart grow fonder, and more curious: Does Kepler-22b have a Congress that shows signs of intelligent life?

First Published December 11, 2011, 5:00 a.m.