Guest Stars Chiara Mingarelli as Herself (Astrophysicist) Greg Leonard as Himself (Astronomer) Cathy Plesko as Herself (Planetary Scientist) Konstantin Batygin as Himself (Planetary Astrophysicist) Paul Chodas as Himself (Director, Center for NEO Studies) Kelly E. Fast as Herself (NEO Observations Program Manager) Andrew Rivkin as Himself (Planetary Astronomer)