Neil deGrasse Tyson

Self - Host

Ann Druyan

Acteur

Brannon Braga

World's Fair Attendee

Carl Sagan

Self (voice) (archive footage)

Seth MacFarlane

Sherwood Rowland (voice)

John Steven Rocha

Bellaramine (voice)

Paul Telfer

Angry Scholar #2 (voice)

Jonathan Morgan Heit

John Herschel (voice)

Cary Elwes

Edmond Halley / Robert Hooke (voice)

Tom Konkle

Samuel Pepys (voice)

Alexander Siddig

Isaac Newton (voice)

Alfred Molina

Ibn al-Haytham (voice)

Richard Gere

Clair Patterson (voice)

Marc Worden

Harrison Brown (voice)

Kirsten Dunst

Cecilia Payne (voice)

Marlee Matlin

Annie Jump Cannon (voice)

Peggy Jo Jacobs

Margaret Harwood (voice)

Amanda Seyfried

Marie Tharp (voice)

Christiane Amanpour

Enheduanna (voice)

Stoney Emshwiller

Acteur

Michael Chochol

Jan Oort

André Sogliuzzo

Christopher Wren (voice)

Oliver Vaquer

Joseph von Fraunhofer (voice)

Christopher Emerson

Acolyte (voice)

Fred Tatasciore

Democritus (voice)

Larry Cedar

Acteur

Piotr Michael

Lab Assistant (voice)

Nick Jameson

Acteur

Michael McConnohie

Acteur

Enn Reitel

Henry Norris Russell (voice)

Keythe Farley

Acteur

Masasa Moyo

Acteur

Maria Frucci

Acteur

Martin Jarvis

Humphry Davy (voice)

Noah Langford

(voice)

Fay Masterson

(voice)

Heiko Obermöller

Einstein's Father (voice)

Julian Ovenden

Michael Faraday (voice)

Jack Rainsford

(voice)

Glenn Steinbaum

Bruce Heezen (voice)

William Salyers

(voice)

Paul Sorvino

Augustin Mouchot (voice)

Eliza Schneider

(voice)

Frank Baxter

Self (archive footage)

John F. Kennedy

Self (voice) (archive footage)

Masoumeh Husseini

Monk (voice)

Harssh A. Singh

Ashoka (voice)

Nick Sagan

Acteur

Clinnette Minnis

Acteur

Shereen Balles

Female Voyager (voice)

Kapeneta Te'o-Tafiti

Male Voyager (voice)

Patrick Stewart

William Herschel (voice)

Joseph Grange

John Herschel (voice)

Carol Bach Rita

Caroline Herschel (voice)

Viggo Mortensen

Nikolai Vavilov (voice)

Ken Lally

(voice)

Phil Crowley

(voice)

Yuri Lowenthal

(voice)

Edita Brychta

(voice)

Christopher Lee Parson

(voice)

Andrew Pifko

(voice)

Brendan Bradley

(voice)

Matthew Jayson Cwern

(voice)

Alan Shearman

(voice)

Natasha Goubskaya

(voice)

Skye Sammoutis

(voice)

Marcelo Tubert

(voice)

Mara Junot

(voice)

Rick Pasqualone

(voice)

Elijah Braik

(voice)

Novi Brown

(voice)

Jamie Hanes

Acteur

Will Greenburg

John Goodricke

Dex de Groot

Acteur

Joep Fellinger

Acteur

Elizardo Torrez

Young Carl Sagan

Steve Oatway

Charles Darwin

Adam Tsekhman

Christiaan Huygens

Neil Arnote

Neil Armstrong

Ernie Vigil

Thomas Young

Judd Hirsch

Robert Oppenheimer (voice)

Joseph J. Micucci

Young Father

Olivia D'Abo

Marie Curie (voice)