Will Smith
Self - Host (10 eps)
Chris Hadfield
Self - Astronaut (10 eps)
Jerry Linenger
Self - Astronaut (9 eps)
Nicole Stott
Self - Astronaut (8 eps)
Mae Jemison
Self - Astronaut (8 eps)
Leland Melvin
Self - Astronaut (8 eps)
Michael J. Massimino
Self - Astronaut (5 eps)
Jeffrey A. Hoffman
Self - Astronaut (5 eps)
Lucas Spelman
Self - CAL Fire Captain (2 eps)
Jonathan Paredes
Self - Cliff Diver (2 eps)
Lama Samdup
Self - Tibetan Buddhist Monk (2 eps)
Iain Kerr
Self - Expedition Leader (2 eps)
Rocky Robinson
Self - Motorcyclist (2 eps)
Peggy Whitson
Self - Astronaut (2 eps)
Felipe Gómez Gómez
Self - Astrophysicist (1 eps)
Kidane Belay
Self - Salt Trader (1 eps)
Heïdi Sevestre
Self - Glaciologist (1 eps)
Nelson Gadea
Self - Head Doctor, La Rinconada (1 eps)
Guillaume Néry
Self - Performance Freediver (1 eps)
Adam Aaronson
Self - Meteorite Dealer (1 eps)
Thomas Senf
Self - Mountaineer (1 eps)
Lukasi Nappaaluk
Self - Inuit Elder (1 eps)
Frank Willems
Self - Conservationist (1 eps)
Ken Sims
Self - Volcanologist (1 eps)
Aldo Kane
Self - Volcanologist (1 eps)
Morgan Sandercock
Self - High-Altitude Glider Pilot (1 eps)
Xiao Qiang
Self - Engineer (1 eps)
Hazel Barton
Self - Microbiologist (1 eps)
Federico Pisani
Self - Biologist (1 eps)
Lee Koon Yau
Self - Engineer (1 eps)
Liane Benning
Self - Biogeochemist (1 eps)
Kenny Broad
Self - Environmental Anthropologist (1 eps)
Roger Smith
Self - Paleontologist (1 eps)
Karla Colmenero
Self - Environmentalist (1 eps)
Tyler Winter
Self - Aquatic Ecologist (1 eps)
Petr Nesterov
Self - Kamchatka Native Dancer (1 eps)
Alina Nesterov
Self - Kamchatka Native Dancer (1 eps)
Ty Bowen
Self - Thunderbolt Lead Pilot (1 eps)
Tim Mousseau
Self - Mutational Biologist (1 eps)
Moahamed El Ghanny
Self - Master Builder (1 eps)
Fandi
Self - Fisherman (1 eps)
Omar Mednia Ramírez
Self - Paleontologist (1 eps)
Isak Mathis Triumf
Self - Sami Reindeer Herder (1 eps)
Chris Perry
Self - Coral Reef Geoscientist (1 eps)
Ra Bun Theurm
Self - Buddhist Monk (1 eps)
Caroline Ciavaldini
Self - Professional Climber (1 eps)
Franco Barattini
Self - Cave Michelangelo CEO (1 eps)
Minoru Kinoshita
Self - Former Resident of Hashima Island (1 eps)
Nichelle Nichols
Self (1 eps)
Logan Doull
Self - Caver (1 eps)
Ian D. MacLeod
Self - Corrosion Scientist (1 eps)
Marlice Van Vuuren
Self - Conservationist (1 eps)
Esentai Bekbolat
Self - Eagle Hunter (1 eps)
Esen Sailau
Self - Eagle Hunter (1 eps)
Uvaserua Tjiposa
Self - Himba Chief's Wife (1 eps)
Julie Misaki
Self - Hong Kong Resident (1 eps)
Beth Whitson
Self - Peggy's Mother (1 eps)
Keith Whitson
Self - Peggy's Father (1 eps)
Abel Méndez
Self - Planetary Astrobiologist (1 eps)
Pak Naspin
Self - Freediver (1 eps)
Rosa Maria dos Santos
Self - Climatologist (1 eps)
Jaime Awe
Self - Archeologist (1 eps)