A small asteroid or comet racing through our solar system may be the first known interstellar visitor, U.S. scientists say — but it won't be around for long.

The object, known as A/2017 U1, was discovered this month by a researcher using a sophisticated telescope system at the University of Hawaii that continually scans the skies for such phenomena.

"We have been waiting for this day for decades," said Paul Chodas, manager of the National Aeronautics and Space Administration's Center for Near Earth Object Studies at the Jet Propulsion Laboratory in Pasadena, California.