The European Space Agency got its new small launcher VEGA off the pad on schedule this morning at 1000GMT, or 0600 local time in Kourou, French Guiana.

The launch couldn’t have been pushed back much further – it had been scheduled for 26 January – because ESA needs to launch Ariane 5 on 9 March to carry its third Automated Transfer Vehicle robotic supply ship to the International Space Station.

Kourou could handle both flights more or less simultaneously, but the two rockets will follow similar trajectories and thus share the same set of ground stations, including some tracking equipment aboard ships that are today in place for the Vega launch but must be repositioned before the ATV flight. Traffic to the ISS is heavy, so 9 March – give or take a day for normal launch delays – is a non-negotiable slot.

Vega has been nine years in the works and will give ESA exceptional flexibility in its operations. The rocket’s sweet spot is to place a 1.5T payload into a 750km orbit, ideal for Earth observation or scientific missions. Soyuz can loft 3T to the very high geosynchronous orbits – its first Kourou payload was a pair of Galileo navigation satellites. Ariane 5 is much bigger, ideal for up to 10T to geosynchronous orbits or heavy loads to the Space Station.