Two further satellites have formally become part of Europe's Galileo satnav system, broadcasting timing and navigation signals worldwide while also picking up distress calls across the planet.

These are the 15th and 16th satellites to join the network, two of the four Galileos that were launched together by Ariane 5 on 17 November, and the first additions to the working constellation since the start of Galileo Initial Services on 15 December.

The growing number of Galileo users around the world will draw immediate benefit from the enhanced service availability and accuracy brought by these extra satellites.

The launch into space and the manoeuvres to reach their final orbits still left a lot of rigorous testing before the satellites could join the operational constellation.

Their navigation and search and rescue payloads had to be switched on, checked and the performance of the different Galileo signals assessed methodically in relation to the rest of the worldwide system.

This lengthy testing saw the satellites being run from the second Galileo Control Centre in Oberpfaffenhofen, Germany, while their signals were assessed from ESA's Redu centre in Belgium, with its specialised antennas.

The tests measured the accuracy and stability of the satellites' atomic clocks - essential for the timing precision to within a billionth of a second as the basis of satellite navigation - as well as assessing the quality of the navigation signals.

Oberpfaffenhofen and Redu were linked for the entire campaign, allowing the team to compare Galileo signals with satellite telemetry in near-real time.

Making the tests even more complicated, the satellites were visible for only three to nine hours a day from each site.

The satellites are now broadcasting working navigation signals and are ready to relay any Cospas-Sarsat distress calls to regional emergency services.

Now that these two satellites are part of the constellation, the remaining pair from the Ariane 5 launch is similarly being checked to prepare them for service.

Tweet

GIS is a powerful tool that should be used with caution
Washington DC (SPX) May 30, 2017
Although computer models of archaeological sites are ideal software tools for managing spatially referenced data and commonly used to yield insights which contribute to the protection of heritage materials, some scientists question their credibility, calling for these long-term trends be 'ground truthed' in order to ensure that calculated rates of change reflect observed phenomena 'in the field' ... read more

Related Links
Galileo at ESA
GPS Applications, Technology and Suppliers

Thanks for being here; We need your help. The Space Media Network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceMediaNetwork Contributor $5 Billed Once credit card or paypal		SpaceMediaNetwork Monthly Supporter $5 Billed Monthly paypal only