Scientists have spotted a new kind of signal in space- four strange, circular objects. Three are particularly bright around their edges, like rings, or bubbles. And they have no idea what they are.

Have we come close to getting the answer on alien existence? Four mysterious, deep circular objects, which were never seen before, have been observed in deep space by massive radio telescopes. The ...

Radio astronomers see what the naked eye can’t. As we study the sky with telescopes that record radio signals rather than light, we end up seeing a lot of circles. The newest generation of radio ...