This document summarizes a presentation given at the ONE Conference 2013 about using cloud computing for Earth observation ground segments. It describes four cases where the European Space Agency used cloud computing:
1. Mass re-processing of satellite data on Amazon Web Services for validation purposes, allowing processing of 30,000 products in 5 weeks.
2. Coupling large data dissemination and processing capabilities on dedicated servers from Hetzner for analyzing 38,000 satellite images and serving 3,000 users.
3. A collaborative exploitation platform using multiple cloud providers through Helix Nebula for exploiting Earth observation data from various sources and making it available to over 200 users.
4. Plans for a sandbox service providing researchers and service providers