GALILEO UPDATE

Europe launches two satellites in the Galileo constellation

With the launch of Galileo 7 and 8, the EU’s Galileo satellite navigation system now has a total eight satellites in orbit. Galileo 7 & 8 lifted off at 21:46 GMT on March 27 from Europe’s Spaceport in French Guiana on top of a Soyuz rocket.

All the Soyuz stages performed as planned, with the Fregat upper stage releasing the satellites into their target orbit close to 23 500 km altitude, around 3 hours 48 minutes after liftoff. The launch is designated VS11 in Arianespace’s numbering system. Flight VS11’s passengers — built by OHB System, with Surrey Satellite Technology Ltd. supplying the navigation payloads — are the third and fourth Full Operational Capability (FOC) satellites in the Galileo program, which is creating a Europeanoperated space-based navigation system.

Following initial checks, run jointly by ESA and France’s CNES space agency from the CNES Toulouse centre, the two satellites will be handed over to the Galileo Control Centre in Oberpfaffenhofen, Germany and the Galileo in-orbit testing facility in Redu, Belgium for testing before they are commissioned for operational service. This is expected in mid-year. ESA

ESA successfully corrects sixth Galileo satellite’s orbit

The ESA has successfully corrected the orbit of its sixth Galileo satellite following its launch into an elongated orbit in August 2014. It took 14 maneuvers to reposition the probe, which is designed to form part of a new global navigation system on par with existing GPS and Glonass solutions.

The fifth and six Galileo satellites were launched together in August 2014, and are designed to follow the same path on their course around Earth, orbiting on opposite sides of the planet. Due to a malfunction during assent, the two satellites were launched into a lower orbit than intended, with the sixth probe hitting altitudes of between 13,713 km (8,521 miles) and 25,900 km (16,094 miles), bring it into contact with the harmful Van Allen Belt.

The plan to recover the sixth satellite to an operational orbit was devised by the ESA’s Galileo team in conjunction with the agency’s ESOC operations center, SpaceOpal and the CNES space agency. The operation began in January, taking six weeks and including 14 separate maneuvers. The team worked to slowly raise the lowest point of the orbit by more than 3,500 km (2,175 miles) while making it more circular.

The sixth satellite joins the fifth, the orbit of which also required correction after launch, with 11 adjustments being completed in November 2014. The two probes will now work in tandem, but they’ll require significant testing before they can become operational. ESA