Galileo Satellites Being Prepped For Launch
September 10, 2012

Next Pair Of Galileo Satellites Getting Prepped For October Launch

Lee Rannals for - Your Universe Online

The second pair of Galileo navigation satellites is being prepared for launch from Europe's Spaceport in October.

The third Galileo satellite's propellant tank will be getting filled with hydrazine fuel this week, and the fourth will be getting its propellant tank filled next week.

The twin satellites will be hitching a ride aboard the Soyuz ST-B on October 10, then will meet up with the first two Galileo satellites currently in orbit.

The fourth Galileo satellite arrived at Cayenne Airport in French Guiana on August 17, while the third satellite arrived at the facility on August 7.

The satellites will be operating from medium orbit 33 about 140 miles above the Earth.

Having four satellites is the minimum number required for navigational fixes, enabling full system testing whenever they are all visible in the sky.

These validation tests will be followed by the deployment of more satellites and ground segment to achieve "Full Operational Capability."

The European Space Agency (ESA) said back in December of last year that its first Galileo satellite transmitted test signals across its full spectrum.

Twenty-two of the planned satellites are being built by OHB in Germany, which is responsible for the platforms and final satellite integration.  The U.K.'s Surrey Satellite Technology will be producing the payloads for the satellites.

EADS Astrium in Germany built the first four Galileo satellites and produce the platforms, while Astrium U.K. built the payloads.

The four Galileo satellites were assembled and tested in Rome by Thales Alenia Space.