The radio telescope at the Arecibo Observatory in Puerto Rico can do something that most radio telescopes can't: it can transmit. And that's useful for something other than sending messages to the stars: it might just help save the world one day. More about the Arecibo Observatory: http://www.naic.edu/ Behind the Scenes, including helmet-cam footage of the walk to the telescope, over on the Park Bench: https://www.youtube.com/watch?v=QZAWqk-wrzc Camera and audio mix: Matt Gray http://mattg.co
