The ‘Cities Beyond Earth’ Public Debates, held on 22 January in Madrid, explored the remarkable confluence of space colonies and the sustainability of our cities on Earth.

As humanity increasingly ventures into the cosmos, the lessons learned from building and maintaining self-contained habitats beyond our planet hold immense relevance for the cities we inhabit today. Our world faces unprecedented challenges, from climate change to resource scarcity, and the urgency to create more resilient, sustainable urban environments has never been greater. By studying space colonies, we can gain critical insights into efficient resource management, closed-loop ecosystems, and innovative technologies that can be harnessed to improve the sustainability and resilience of our terrestrial cities to avert the collapse of our model to inhabit the Earth.