Tess will systematically scan the sky

The US space agency is launching a new telescope that should find thousands of planets beyond our Solar System. The Tess mission will survey nearly the entire sky over the course of the next two years. It will stare at stars, hoping to catch the dip in brightness as their faces are traversed by orbiting worlds. Sara Seager is from the Massachusetts Institute of Technology (MIT), which leads the project. She explained the Tess observation strategy.