When I was young, the Byrds recorded a song called “CTA-102,” immortalizing the dully named planet, in a faraway solar system, that scientists at the time suggested may have been throwing off radio signals that were signs of intelligent life. Nothing came of that, except for a fun song – but today, technology allows us to be a little more hopeful. Part of that modern technology is the Kepler telescope, which has identified hundreds of potential Earth-like planets and environments – including one, isolated in tonight’s documentary, given the catchy name of Kepler-22b. Another name that, like CTA-102, clearly is for the Byrds… Check local listings.