March 7, 2017


CNES’s Proteus series of spacecraft buses is designed for satellites in the 500-700-kg class operating in low-Earth orbit.

CNES began development of its Proteus bus (Plateforme Reconfigurable pour l'Observation, les Télécommunications et les Usages Scientifiques) in 1996. Its main goal was to offer cheaper space access through a standardized series of spacecraft buses to foster new missions for satellites weighing 500 to 700 kg.

The JASON-1 altimetry satellite was the first to be built around a Proteus bus. Launched in 2001, its mission was officially terminated by CNES and NASA in 2013 after more than 11 years in orbit, far exceeding Proteus’s 3-year design life. Four more missions using Proteus would follow: CALIPSO, launched in 2006 by a Delta II vehicle; COROT the same year by a Soyuz launcher; JASON-2 in 2008 by Delta II; and SMOS in 2009 by a Rockot launcher. The last Proteus bus in the series is flying on the JASON-3 mission launched in 2016.

Initiated by CNES, the Proteus series was conceived and built in partnership with Thales Alenia Space. Besides the bus design, it also called for the development of an orbit control ground segment. CNES’s Myriade bus for satellites in the 100-200-kg class and Myriade-Evolutions bus for satellites in the 350-400-kg class draw on the heritage of Proteus.