U.S. television network CBS says it ordered 13 episodes of \"Extant,\" a futuristic thriller from Steven Spielberg\'s Amblin Television and CBS Television Studios. To be broadcast next summer, the show is about a female astronaut trying to reconnect with her family when she returns after a year in outer space. No casting has been announced yet. \"\'Extant\' is a very original concept with layers of humanity, mystery and surprise that reveal itself throughout the script,\" Nina Tassler, president of CBS Entertainment, said in a statement Wednesday. \"Our partnership with Amblin for \'Under the Dome\' showed that viewers respond to high-quality event programming in the summer. We look forward to building on that with \'Extant\' and offering CBS audiences another high-concept, unique event for summer television.\"