Galaxy Scale Megastructures & Kardashev 3 Civilizations

Imagine engineering projects so vast they mold galaxies into new shapes. We’ll explore the staggering feats of Kardashev-3 and beyond civilizations, crafting CARD galaxies, Birch Planets, and even rearranging superclusters.

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Credits:
Spaceport Innovations - Designing the Next Generation of Launch Sites
August 3, 2025; Episode 746
Written, Produced & Narrated by: Isaac Arthur
Galaxy-Scale Megastructures & Kardashev-3 Civilizations
Written by: Isaac Arthur
Editor: Darius Said
Graphics: Jeremy Jozwik, Ken York, Sergio Botero, Steve Bowers
Select imagery/video supplied by Getty Images
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Stellardrone, "Endeavour", "Red Giant", &"Billions and Billions"

Chapters
0:00 Intro
1:38 The Power of a Galaxy
4:02 Compact Artificial Red Dwarf Galaxies – CARD Galaxies
11:18 No-FTL Civilizations: Patience and Proliferation
15:37 Moving the Stars
19:26 Rearranging Galaxies and Superclusters
29:38 Black Holes as Galactic Waypoints and Interstellar Hubs
33:11 Birch Planets: The Final No-FTL Civilization
42:25 Faster-Than-Light Civilizations: Beyond the Light Barrier