Carl Sagan as Self (archive footage)

John Casani as Self

Lawrence Krauss as Self

Carolyn Porco as Self

Timothy Ferris as Self

Edward Stone as Self

Nick Sagan as Self

Larry Soderblom as Self

Charley Kohlhase as Self

Fran Bagenal as Self

James F. Bell as Self

Frank Locatell as Self

Suzanne Dodd as Self

Jon Lomberg as Self

Heidi Hammel as Self

Candy Hansen as Herself

Andrew Ingersoll as Himself

Dave Linick as Himself

Fernando Peralta as Himself

Linda J. Spilker as Herself

Tom Spilker as Himself

Janet Sternberg as Herself

Amahl Drake as Herself

Don Gurnett as Himself

Stamatios Krimigis as Himself

Linda Morabito as Herself

Bradford A. Smith as Self - Imaging Science Team Leader

Richard John Terrile as Self

Frank Drake as Self