The no. 2 Vega light-lift launcher has been fitted with its solid propellant third stage, marking another milestone in preparations for its April mission from French Guiana with a multi-satellite payload.

In the latest activity at the Spaceport's ZLV launch site, Vega's Zefiro 9 stage was installed atop its lower two solid propellant stages, which were stacked during previous integration activity.

This clears the way for a "top off" of the basic Vega launcher with its bi-propellant liquid upper stage Attitude and Vernier Upper Module, which performs the attitude control and axial thrust functions during the final stages of flight - enabling the payload to be placed in orbit.

The flight next month will carry the Proba-V, VNREDSat-1A and ESTCUBE-1 satellites, and follows Vega's on-target maiden launch in February 2012 with a payload of nine spacecraft - which served as its qualification mission.

Created by Europe as a capable lightweight launcher, Vega is tailored to orbit small- to medium-sized satellites, including institutional and scientific spacecraft. It joins the two other members of Arianespace's vehicle family: the medium-lift Soyuz and heavyweight Ariane 5.

Vega resulted from a European Space Agency program led by Italy's ASI space agency and industrial prime contractor ELV SpA.