LEON is a 32-bit CPU microprocessor core, based on the SPARC-V8 RISC architecture and instruction set.
It was originally designed by the European Space Research and Technology Centre (ESTEC), part of the European Space Agency (ESA), and after that by Gaisler Research (now Aeroflex Gaisler). It is described in synthesizable VHDL.
LEON has a dual license model: A LGPL/GPL FLOSS license that can be used without licensing fee, or a proprietary license that can be purchased for integration in a proprietary product. The core is configurable through VHDL generics, and is used in system-on-a-chip (SOC) designs both in research and commercial settings.
ESA's Alphasat telecom satellite, the Proba-V microsatellite, the Earth-monitoring Sentinel family and the BepiColombo mission to Mercury are among the missions to use an advanced 32-bit microprocessor – engineered and built in Europe.
All of them incorporate the LEON2-FT chip, commercially known as the AT697. Engineered to operate within spacecraft computers, this microprocessor is manufactured by Atmel in France but originally designed by ESA.