October 1, 2012
Twin Galileo Satellites Fueled Up And Ready For October Launch
Lee Rannals for redOrbit.com - Your Universe Online
The twin Galileo satellites are now fueled and ready for the launch planned for the evening of October 12, according to the European Space Agency (ESA).ESA said that technicians filled up the two satellites' tanks with hydrazine fuel, which is used to maintain the satellites' attitude and orbital position during their 12-year lifetime.
The Galileo satellites will be transported to medium orbit by the Fregat fourth stage of their Soyuz ST-B launcher. This launch technique allows the two Galileo satellites to be launched together aboard the Soyuz, or in groups of four if driven up by the new Ariane 5.
The satellites are now attached to a special dispenser that holds them securely in position during launch. After launch, pyrotechnic devices will release them sideways in opposite directions once they're at about 14,500 miles altitude.
ESA said the satellites are equipped with aluminum plates on each side to protect their solar panels. These plates will be removed later once in orbit.
The Galileo satellites, along with the dispenser and Fregat upper stage, will now be checked out ahead of Thursday's fitting of the protection launch fairing.
The two satellites launch readiness review will begin the start of the following week, according to the space agency.
Assuming the launch readiness goes according to plan, the combined "Upper Composite" will be moved from the Fregat Integration Building to the launch pad, where it will be attached to the Soyuz launcher.
The new Galileo In-Orbit Validation satellites will be joining the first two that have been orbiting since October 2011.
"This is a significant milestone for Europe´s Galileo program because four is the minimum number required for navigational fixes, enabling full system testing whenever they are all visible in the sky," ESA said in a press statement.
The space agency said this validation phase will be followed by the deployment of more satellites and ground segment components to achieve "Full Operational Capability."
The first four Galileo satellites were built by a consortium led by EADS Astrium, Germany, with Astrium producing the platforms and being responsible for the payloads. Thales Alenia Space assembled and tested the equipment in Rome.