Orbital Arcologies: Mega-Cities in Space

Sep 4, 2025 Megastructures & Extreme Engineering
From O’Neill cylinders to spiral habitats, discover how humanity might build colossal, interconnected cities high above Earth.

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Credits:
Orbital Arcologies - Mega Cities in Space
Written, Produced & Narrated by: Isaac Arthur
Graphics: Bryan Versteeg, Jeremy Jozwik, Katie Byrne, Udo Schroeter
Select imagery/video supplied by Getty Images
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

Chapters
0:00 Intro - The Conductor’s Tale
4:43 Why Megacities in Space?
6:02 The Four Foundational Assumptions of Space Habitat Design
10:11 Flawed Assumptions & Specialized Habitats
11:28 The Urban Web – Tethered Transit and Megacity Growth
17:14 Nebula
18:24 Spiral Habitats – A Rolled-Up City in Space
20:19 Density and Design – Population Scaling
23:17 Green Limits – CO₂, Heat, and Living Space
26:08 The Future of Orbital Urbanization – Terran Swarms and Beyond