Starcloud's Philip Johnston: Why the Cheapest Compute Will Be in Space

Philip Johnston, co-founder and CEO of Starcloud, takes the AI Ascent 2026 stage to make the case that the future of AI compute is in orbit. He walks through the economics of building data centers in space: why one square meter of solar in space generates eight times the energy of one on Earth, why launch costs only need to fall to $500/kg before space-based compute becomes cheaper than terrestrial, and why he thinks Starship gets us there. He also previews Starcloud's plan: an 88,000-satellite constellation that would deliver 20 gigawatts of inference capacity in low Earth orbit, optically linked, always in the sun. Plus what it took to train the first model in space, why this is the start of the largest infrastructure project ever, and what a five-gigawatt, four-kilometer-wide data center in space might actually look like. 00:00 Introduction 00:32 StarCloud 1 GPU Demo 01:01 Proving GPUs Work in Space 01:43 Why Space Data Centers 02:49 Launch Cost Break-Even 03:17 88,000-Satellite Vision 04:42 Heat Dissipation Math 06:42 Debris and Kessler Risk 08:39 Radiation and Bit Flips 09:23 Inference Focus and Timeline