Engineers at the European Space Agency’s control centre are busy trying to figure out whether there could be any navigational use of the two Galileo satellites stranded in an incorrect orbit after the Friday launch failure.
The two spacecraft, each worth €40m, are the first Full Operating Capability satellites of the foreseen 30-strong global navigation satellite system (GNSS), to have been launched. However, the major milestone on the way towards Europe’s very own civilian navigational constellation turned into a bitter fiasco after the two spacecraft were left stranded in an elliptical orbit instead of the required circular orbit.
An investigation has been launched trying to determine the cause of the glitch, which left the satellites orbiting around an ellipse with the farthest point at about 25,000km and the nearest only about 13,000km away from Earth.
The Galileo constellation of 30 satellites is designed to circle the Earth at the altitude of about 23,500km in strictly circular orbits with exactly defined inclination towards the equator for each satellite.
The focus of the investigation is on the Fregat upper stage of the Russian-made Soyoz rocket, which lifted the two satellites from Europe’s spaceport in Kourou, French Guiana, on Friday.
According to Russian Space Web, the investigators in Moscow believe that two out of 12 thrusters of the NPO Lavochkin-made Fregat upper stage, used to keep the rocket in right orientation during unpowered flight, experienced problems during firing. As a result, the rocket was positioned incorrectly when the main engine was ignited, injecting the two satellites into the wrong orbit with incorrect inclination towards the equator.
Esa announced on Thursday that both satellites are under control with their solar panels deployed, generating power. The agency’s engineers, together with teams from the French space agency CNES, are trying to determine how to make the best use of the two unfortunate satellites.
Due to the limited amount of fuel on board of the satellites, it’s impossible to correct their orbit as the difference is too big.
Esa, together with Arianespace, the operator of Europe’s launch facility in Kourou, French Guiana, and the European Commission, has launched a separate investigation into the cause of the mishap, which will most likely delay Europe’s plans to roll out Galileo’s services.
Before the Friday glitch, Esa planned to launch additional two satellites aboard a Soyuz rocket by the end of this year and continue launching afterwards using domestically manufactured Ariane 5.
The Galileo constellation, Europe’s response to the US Air Force operated GPS, will consist of 30 satellites, manufactured by a consortium of European companies led by German OHB Systems as part of a £4.34bn contract.
The Galileo programme, offering better positioning precision than the GPS constellation, is managed by the European Commission together with Esa serving as a technical agent.
Before the Friday mishap, the European Commission hoped to have the already delayed system fully operational by 2017.