
Narrator / Himself - Narrator
Mike Rowe

Narrator
Erik Dellums

Himself - Cosmologist
Lawrence Krauss

Himself
Michio Kaku

Herself - Astronomer
Michelle Thaller

Stephen Hawking

Himself - Astronomer
Phil Plait

Himself - Narrator
Richard Lintern

Himself - Astrophysicist
James S. Bullock

Herself - Planetary Protection Engineer
Moogega Cooper

Herself - Cosmologist
Katie Freese

Himself - Astrophysicist
Hakeem Oluseyi

Himself - Theoretical Physicist
Max Tegmark

Dan Durda