Next week the European Space Agency begins its final push to establish an independent global satellite navigation system. Four new satellites are scheduled for launch atop a specially converted European Ariane 5 rocket at 13:06 GMT on 17 November.
The launch will take place from Europe’s spaceport at Kourou, French Guiana. Until now, the satellites have been launched two at a time using Russian Soyuz rockets, again launched from Kourou.
Known as Galileo, the European satellite navigation system will need 24 working satellites to provide positioning, navigation and timing services. Next week’s launch will be the eighth so far and will bring the number to 18.
It will take three and a half hours for the rocket to reach an altitude of 23,200km, which is where the operating orbit is located. This is much higher than the International Space Station (400km) but significantly lower than the communications satellites at 36,000km.
The satellites will be released from the rocket two at a time, and two teams of satellite operators will work in parallel to first make sure the spacecraft are functioning properly, and secondly to guide each pair to their final operational positions within the constellation. Altogether, this phase will take almost a fortnight.
At least two more quadruple deployment flights are scheduled to bring the constellation to operational capacity. They will also furnish it with spare satellites to take over as the others run out of fuel or fail for other reasons.