Sci-fi thrills us with enormous space monsters and Kaiju, but could the galaxy already be home to such leviathans?

Watch my exclusive video The Fermi Paradox: Air https://nebula.tv/videos/isaacarthur-the-fermi-paradox-air
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.

Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE

Credits:
Giant Space Monsters
Episode 427b; January 1, 2024
Produced, Written & Narrated by: Isaac Arthur
Graphics: Jeremy Jozwik, Ken York
Music Courtesy of:
Epidemic Sound http://epidemicsound.com/creator
Select imagery/video supplied by Getty Images

Giant Space Monsters (Narration Only)

The universe is a cold and hostile place, and may be inhabited by ruthless civilizations or machine minds, bent on destroying anything in their way.

Watch my exclusive video Big Alien Theory https://nebula.tv/videos/isaacarthur-big-alien-theory
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.

Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE
Credits:
Xenocide
Episode 486; February 9, 2025
Written, Produced & Narrated by: Isaac Arthur
Editors:Ludwig Luska
Graphics: Darth Biomech, LegionTech Studios
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

Xenocide (Narration Only)

Imagine a scale that ranks civilizations not by their borders or technology, but by the sheer energy they command— some spanning entire galaxies. Join us as we explore the Kardashev Scale, the ultimate measure of cosmic power.


Watch my exclusive video Big Alien Theory https://nebula.tv/videos/isaacarthur-big-alien-theory
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.

Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE
Credits:
The Kardashev Scale & Population
Episode 486; February 13, 2025
Written, Produced & Narrated by: Isaac Arthur
Editors: Ludwig Luska
Graphics: Fishy Tree, Jeremy Jozwik, Ken York YD Visual
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Phase Shift, "Forest Night"
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector", "Oxygen Garden"
Stellardrone, "Red Giant", "Billions and Billions"

The Kardashev Scale & Population

What if the "magic" of tomorrow is just science we don’t yet understand? In this episode, we explore the wildest speculative technologies—faster-than-light travel, Dyson Spheres, teleportation, wormholes, and more. Could these breakthroughs redefine our future or explain the Fermi Paradox? Find out as we dive into the impossible!

Watch my exclusive video Big Alien Theory https://nebula.tv/videos/isaacarthur-big-alien-theory
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.
Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE
Credits:
Impossible Technologies: The Clarketech Compendium 
Episode 486a; February 16, 2025
Written, Produced & Narrated by: Isaac Arthur
Editors: Ludwig Luska, Thomas Owen, Lukas Konecny
Graphics: Jeremy Jozwik, Ken York YD Visual, Mihail Yordanov, Sergio Botero
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Phase Shift, "Forest Night"
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector", "Oxygen Garden"
Stellardrone, "Red Giant", "Billions and Billions"
Lombus, "Hydrogen Sonata", "Cosmic Soup"

Impossible Technologies: The Clarketech Compendium

Imagine a world stretched along a single, endless river inside a colossal space megastructure. Explore the fascinating concept of the Topopolis, a futuristic habitat billions of miles long, where humanity might thrive in a sprawling civilization bound by physics, engineering, and imagination.

Watch my exclusive video Big Alien Theory https://nebula.tv/videos/isaacarthur-big-alien-theory
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.
Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE
Credits:
Topopolis: The Eternal River 
Episode 487a; February 23, 2025
Written, Produced & Narrated by: Isaac Arthur
Graphics: Apogii.uk, Ken York YD Visual, Steve Bowers, Udo Scroeter
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

Topopolis: The Eternal River Space Habitat (Narration Only)

Gravity Tech: The Power To  Reshape Our Civilization... And The Cosmos Themselves

Gravity Tech: The Power To  Reshape Our Civilization... And The Cosmos Themselves (Narration Only)

If civilizations can endure for eons and people can live indefinitely, what drives progress, ambition, and purpose in a world where time has no limit? Would an ageless society be a utopia of infinite wisdom, or a stagnating empire struggling to keep ambition alive across the centuries?

Watch my exclusive video The End of Science https://nebula.tv/videos/isaacarthur-the-end-of-science
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isaacarthur
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.

Visit our Website: http://www.isaacarthur.net
Join Nebula: https://go.nebula.tv/isaacarthur
Support us on Patreon: https://www.patreon.com/IsaacArthur
Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur
Facebook Group: https://www.facebook.com/groups/1583992725237264/
Reddit: https://www.reddit.com/r/IsaacArthur/
Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content.
SFIA Discord Server: https://discord.gg/53GAShE
Credits:
Methuselah Civilizations: A Society of the Ageless 
Episode 489; March 6, 2025
Written, Produced & Narrated by: Isaac Arthur
Edited by: Ludwig Luska
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector", "Oxygen Garden", "Wonder Cycle"
Stellardrone, "Red Giant", "Billions and Billions"