Philip Johnston
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Sourcery · Inside Starcloud’s $2B Space Factory
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Why Is Shooting Down a Satellite So Hard?
Philip Johnston says shooting down a satellite is a lot harder than blowing up a data center in Virginia, because satellites travel at about 17,000 miles an hour. A kinetic hit at that speed is very difficult.
Starlink is the case study. Starlink is being used in Ukraine, Star Shield is too, and the Russians are not happy about it. Cyber tactics and physical tactics are already visible on Starlink. Starcloud uses the same kind of cryptography so the satellites stay secure from that side.
Anything bigger than a one inch cube can be tracked in space, so an approach would show up. Tampering with the satellites would be an act of war on the US. The Outer Space Treaty governs what cannot be don
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Why Does Everyone Leave a Starcloud 2 Test?
Philip Johnston says everyone leaves the building for a Starcloud 2 vibration test because a xenon tank under the satellite has about half the explosive power of a hand grenade if it explodes.
Vibration tables themselves are pretty safe, and the magnet does not shoot out. The worst outcome is that the hardware under test explodes. Underneath Starcloud 2 is a xenon tank for the thrusters, so the team is not running the test today. When the test does run, everybody has to leave the building. The whole satellite goes on the table, and the solenoid can flip up so the same hardware can be tested along two axes. A toy manufacturer keeps storage across the street and has no idea what is going on i
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What Is Starcloud One Doing With Satellite Imagery?
Philip Johnston says Starcloud One runs inference on satellite imagery in orbit, so the coordinates of a vessel can come down in minutes rather than hours and days.
Starcloud One carries three chips from Nvidia, two from ARM, and CPUs from AMD. Earlier workloads included training NanoGPT from Andrej Karpathy, the first model trained in space, and running the first version of Gemini. The chips are mainly in a test phase now. The useful work is inference for government customers on synthetic aperture radar and hyperspectral data. Military satellites collect enormous amounts of imagery. Reaching a ground station takes at least an hour and a half, and the amount that gets downlinked is usually
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Why Would Anyone Put a Data Center in Orbit?
Philip Johnston says a data center in orbit gets cheaper than one on Earth once launch falls to about $500 a kilogram. A new solar project built to power a ground data center has three big costs. Permitted land is the biggest, and the price depends on location. Batteries for backup power are second. The solar cells themselves are last.
In space, permitted land is unnecessary, so the biggest cost is gone. Batteries are unnecessary because the panels stay in the sun around the clock. The design needs about eight times fewer solar cells, because one square meter of panel in space produces about eight times the energy. Launch is the new cost. Running those numbers is where the $500 a kilogram l
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Where Are Most New Satellites Built?
Philip Johnston says Starcloud is based in the Seattle region because 90% of all satellites launched in the last few years by mass were designed, built, and tested in Redmond, Washington.
He and Ezra Feilden spent the first month of the company in El Segundo. A LinkedIn search for a spacecraft thermal engineer kept returning Redmond, Bellevue, and Seattle, so they moved. About half the team formerly worked at SpaceX. The other half came from the hyperscalers, with AWS and Azure down the road.
For data centers in space, the mix of satellite builders and cloud engineers makes the Seattle region the best place in the world to build Starcloud.
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How Much Did Starcloud Pay for a Broken Vibration Table?
Philip Johnston says Starcloud bought a secondhand broken vibration table for 200 grand after the team could not find a table in the US that would test a pressure vessel in time. A new vibration table costs about $1.5 million, and the lead time is almost two years.
Starcloud 1 is launched. Starcloud 2 is in the assembly facility, midway through move-in, with boxes everywhere. Two lasers sit on top, with deployables and about a 120 foot wingspan, and the satellite has just been through vibration testing. The team worked all weekend to fix the broken table. A welded mock-up of the Starcloud 3 chassis is in the fab shop to show the size. Newer facilities come online next year.