CNES projects library

March 5, 2019

Alphabus

Developed at the initiative of CNES and ESA, the Alphabus platform is designed for high-power telecommunications satellites. Launched for the first time in 2013, it offers technologies that are set to benefit a whole new generation of satellites.

Today’s telecommunications satellites deliver a whole range of services from Internet access and high-definition TV to mobile services. As a result, their payloads are getting heavier and more powerful by the year. To match this trend, a spacecraft bus was needed to fly and power such payloads (the bus is the ‘vehicle’ that carries the payload). CNES and ESA therefore joined forces to develop Alphabus, a cutting-edge spacecraft bus able to support payloads of up to 2 tonnes and with a maximum power rating of 22 kW—in other words, a bus with much more capacity than anything ever flown before (previous payloads did not exceed 1 tonne and 14 kW).

Initiated in 2001 by CNES and ESA, the Alphabus programme was developed in partnership with EADS Astrium and Thales Alenia Space—the Alphabus prime contractors—and numerous European subcontractors. Launched for the first time on 25 July 2013 with Inmarsat’s Alphasat, Alphabus offers technologies that are set to benefit a whole new generation of telecommunications satellites.