Was it NASA's new call for aliens, the future of a secretive Air Force space plane or something else?
Interstellar travel is the ability to travel between stars in the exploration of space. In science fiction, interstellar travel is often depicted as faster-than-light, such as warp drive on "Star Trek" or light speed in "Star Wars," but research is underway to build robotic probes for Alpha Centauri (as in the Breakthrough Starshot project), and to develop hibernation systems, generation ships and other long-duration space technology needed to one day send astronauts to other stars. Learn more about interstellar travel and technology.
Far-out ideas on how to visit another star will be discussed this weekend at the 100 Year Starship Symposium.
Dense filaments of gas shine in the IC5146 interstellar cloud, in an infrared photo from ESA's Herschel space observatory.
Don't expect cuddly, squishy E.T.s to come calling someday; instead, picture robots descending from the sky.
The energy inherent in gravitational corridors would make ideal space lanes for interstellar travel.
A new space telescope that aims to investigate the edge of the solar system is set to launch Sunday.