The mysterious outage that knocked out EU's Galileo GPS services for a week Watch Now

The European Global Navigation Satellite Systems Agency (GNSS) had said the days-long outage as a result of an incident last week that knocked out the Galileo satellite constellation's GPS navigation services has now been fixed.

"Galileo Initial Services have now been restored. Commercial users can already see signs of recovery of the Galileo navigation and timing services, although some fluctuations may be experienced until further notice," GNSS said. "A team composed of GSA experts, industry, ESA and Commission, worked together 24/7 to address the incident. The team is monitoring the quality of Galileo services to restore Galileo timing and navigation services at their nominal levels."

GNSS originally said the incident was the result of an equipment malfunction in the Galileo control centers but later updated this to say the problem was with "ground infrastructure" affecting the calculation of time and orbit predictions, and which are used to compute the navigation message. "The malfunction affected different elements on the ground facilities," it said.

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The agency earlier this week revealed "a technical incident related to its ground infrastructure", but that information only came to light four days after the outage began and no details on the precise cause have been given yet.

"We will set an Independent Inquiry Board to identify the root causes of the major incident. This will allow the Commission, as the programme manager, together with the EU Agency GSA to draw lessons for the management of an operational system with several millions of users worldwide," GNSS said.

In an update Wednesday, the agency had said experts from GNSS, industry, the European Space Agency and the European Commission were "implementing and monitoring recovery actions" for the incident.

"The key objective is to restore the Galileo navigation and timing services for users as soon as possible," GSA said at the time. "Based on the results of the troubleshooting activities, several elements of the ground infrastructure were re-initiated. The progress is being closely monitored," it said.

"As soon as the incident was declared, an Anomaly Review Board was convened and urgent recovery procedures were activated in the affected Galileo infrastructures. Operational teams are working on recovery actions 24/7 to restore the Galileo navigation and timing services as soon as possible."

One impact of the incident was that positioning data was nowhere near as accurate as it should be. According to Italy-based researchers at The Navigation Signal Analysis and Simulation (NavSAS) Group, Galileo was producing positioning information that is 500 meters off the mark.

According to Politico, a European Commission official said a full report would be released once the problem has been resolved, but added that it couldn't provide a "running commentary" on the specific technical issues, in part because it fears that those concerns could expose weaknesses in Galileo before they're fixed.

While Galileo's navigation services were unavailable, devices like smartphones could instead rely on positioning from other US satellites. Galileo search and rescue services remain available.

The Galileo satellite constellation is Europe's multi-billion euro European-controlled alternative to the US satellite navigation system. It was launched in part due to fears that a loss of satellite navigation across Europe could cost billions. In support of the Galileo project, GNSS argued a EU-wide navigation outage for just a few days would cost more than Galileo's development phase.

Galileo "initial services" commenced in 2016 with 26 satellites orbiting the Earth, promising more accurate positioning for end users. Europe is aiming for it to be fully operational by 2020, but such an extended outage could thwart those plans.

GNSS defended its strategy, explaining that the initial services phase was precisely to iron out issues like this before moving to a fully operational phase.