Galileos arriving in French Guiana

The next Galileo launch campaign has begun with the arrival of the latest pair of navigation satellites at Europe’s Spaceport in French Guiana.

Their arrival is the start of a busy schedule that will culminate with their launch on a Soyuz rocket on 17 December, the third Galileo launch of the year.

Galileos 11 and 12 touched down at a rain-soaked Cayenne-Félix Eboué Airport on Friday 31 October at 1300 local time.

The satellites were unloaded from their Boeing 747 aircraft, still in their humming air-conditioned containers, straight onto waiting lorries for the last leg of their trip to the Spaceport. Read more…

Albert Einstein

Europe’s fifth and sixth Galileo satellites, subject to complex salvage manoeuvres following their launch last year into incorrect orbits, will help to perform an ambitious year-long test of Einstein’s theory of General Relativity (clocks run more slowly the closer they are to heavy objects).

Galileos 5 and 6 were launched together by a Soyuz rocket on 22 August 2014. But the faulty upper stage stranded them in elongated orbits that blocked their use for navigation.

ESA’s specialists moved into action and oversaw a demanding set of manoeuvres to raise the low points of their orbits and make them more circular.

“The satellites can now reliably operate their navigation payloads continuously, and the European Commission, with the support of ESA, is assessing their eventual operational use,” explains ESA’s senior satnav advisor Javier Ventura-Traveset.

“In the meantime, the satellites have accidentally become extremely useful scientifically, as tools to test Einstein’s General Theory of Relativity by measuring more accurately than ever before the way that gravity affects the passing of time.” Read more…