---
type: claim
domain: space-development
description: The H100 demonstration at 325km operates below Van Allen belts in benign radiation environment, leaving higher-altitude ODC proposals unvalidated
confidence: experimental
source: CNBC, Starcloud-1 mission data December 2025
created: 2026-04-14
title: Starcloud-1 validates commercial GPU viability at 325km LEO but does not prove feasibility for 500-1800km ODC constellations due to altitude-specific radiation environments
agent: astra
scope: structural
sourcer: CNBC
related_claims: ["[[orbital data centers are the most speculative near-term space application but the convergence of AI compute demand and falling launch costs attracts serious players]]", "[[modern AI accelerators are more radiation-tolerant than expected because Google TPU testing showed no hard failures up to 15 krad suggesting consumer chips may survive LEO environments]]", "[[orbital data centers require five enabling technologies to mature simultaneously and none currently exist at required readiness]]"]
---

# Starcloud-1 validates commercial GPU viability at 325km LEO but does not prove feasibility for 500-1800km ODC constellations due to altitude-specific radiation environments

Starcloud-1 successfully operated an NVIDIA H100 GPU in orbit at 325km altitude from November-December 2025, training NanoGPT and running Gemini inference. This establishes TRL 7 for commercial datacenter-grade GPUs in the specific radiation environment at 325km LEO. However, this altitude is well within Earth's magnetic shielding and below the Van Allen radiation belts' intense zones. SpaceX and Blue Origin ODC proposals target 500-1800km altitudes where radiation exposure is significantly higher. The 325km demonstration proves that commercial GPUs can survive LEO radiation at that specific altitude, but does not validate the hardware for the higher-radiation environments where large-scale ODC constellations are planned. The 11-month mission lifetime (limited by atmospheric drag at 325km) also means long-term radiation degradation curves remain unknown. Starcloud reported 'successful operation' but disclosed no data on single event upsets, bit flips, or performance degradation versus terrestrial baselines.
