Guest Stars Matthew O'Dowd as Himself (Astrophysicist) Grant Tremblay as Himself (Astrophysicist) Alex Filippenko as Himself (Astrophysicist) Max Tegmark as Himself (Theoretical Physicist) Sean Carroll as Himself (Theoretical Physicist) Katherine Freese as Herself (Cosmologist) Uncredited Sheperd S. Doeleman as Himself (Astronomer (archive footage))
