@CNN: A mysterious trail of light appeared in the sky in Northern California last night, sparking online chatter about whether it was a UFO. NASA Astronomer Bill Cooke will answer your questions about this celestial mystery. Join us on Facebook Watch at 6:25p ET https://t.co/1RlN9bnIez https://t.co/hoY11FoOFv

@CNN: A mysterious trail of light appeared in the sky in Northern California last night, sparking online chatter about whether it was a UFO. NASA Astronomer Bill Cooke will answer your questions about this celestial mystery. Join us on Facebook Watch at 6:25p ET https://t.co/1RlN9bnIez https://t.co/hoY11FoOFv