Astronomers on Wednesday confirmed the discovery of an interstellar object racing through our Solar System – only the third ever spotted, though scientists suspect many more may slip past unnoticed.

The object, a celestial body from another star system, was discovered on Tuesday by the University of Hawaii’s Asteroid Terrestrial-impact Last Alert System, or ATLAS, team. At this point, it remains unclear what the object may be or look like as it moves near Jupiter.

It currently sits around 420 million miles (or 670 million kilometres) from Earth. Astronomers have since confirmed its foreign origin—it’s only the third known comet to travel from beyond our solar system.