This artist's illustration shows the first interstellar asteroid, 'Oumuamua. This unique object was discovered on Oct. 19, 2017 by the Pan-STARRS 1 telescope in Hawaii. Subsequent observations from ESO's Very Large Telescope in Chile and other observatories around the world show that 'Oumuamua seems to be a dark red highly elongated metallic or rocky object, about 1,300 feet (400 meters) long, and is unlike anything normally found in the solar system.