WASHINGTON :Astronomers are tracking a newly spotted comet hailing from parts unknown, only the third time such an interstellar object has been observed visiting our solar system. According to U.S. space agency NASA, the interloper - named 3I/ATLAS - was first spotted on Tuesday by an Asteroid Terrestrial-impact Last Alert System, or ATLAS, telescope located in Rio Hurtado, Chile. Astronomers said its unusual trajectory indicated it had ventured from beyond our solar system. Journeying at a