European satnav system will get its first spacecraft

Oct 5, 2011 07:34 GMT  ·  By
This is the Galileo In-Orbit Validation (IOV) ProtoFlight Model (PFM) satellite, which will fly aboard the Soyuz rocket on October 20, 2011
   This is the Galileo In-Orbit Validation (IOV) ProtoFlight Model (PFM) satellite, which will fly aboard the Soyuz rocket on October 20, 2011

Officials at the European Space Agency (ESA) say that the first two spacecraft of the Galileo satellite navigation constellation are now fueled. At this point, the two vehicles are scheduled to launch on October 20, aboard a Russian-built rocket.

The mission will take off from the Kourou Spaceport in French Guiana, South America, where ESA operates its primary spaceport. A three-stage Soyuz rocket and a Fregat-MT upper stage will carry the satellites high above the Earth's surface.

In order to be able to construct Galileo more efficiently, the space agency decided some years ago to sign an agreement with the Russian Federal Space Agency (RosCosmos) for constructing an entire Soyuz launch pad at Kourou.

The facility was completed and dedicated earlier this year, and now experts say that it's ready to see its first launch. Everyone has been waiting for this two satellites to finally take up their positions in orbit, marking a critically-important milestone on constructing Galileo.

Both Galileo In-Orbit Validation (IOV) spacecraft arrived in South America last month, aboard impressive Antonov airplanes. They were transported to Kourou, checked for errors, and then prepared for launch. Now, they are fueled and ready to be mated with their delivery system.

Ultimately, the vehicles are destined to enter an orbit around 23,222 kilometers (14,430 miles) above the surface of the planet. They will be inserted in position by an especially-built dispenser, which will hold the satellites together with inside the Fregat-MT upper stage.

“The first two Galileo IOV satellites, launched this month, will be followed next year by two more. This quartet of satellites, built by a consortium led by EADS Astrium Germany, will form the operational nucleus of the full Galileo satnav constellation,” an ESA press release explains.

“They combine the best atomic clock ever flown for navigation – accurate to one second in three million years – with a powerful transmitter to broadcast precise navigation signals,” the statement goes on to say.

Over the next few years, the Soyuz rockets ESA acquired from RosCosmos will make a nice addition to the agency's existing rocket roaster, which includes the massive Ariane V and the medium-class Vega delivery systems.