New ESA facility puts satnav at the service of science

News from the European Space Agency (ESA)

Global satellite navigation systems are continuously bathing Earth in satnav signals. As well as helping in our daily lives, these signals are also tools for cutting-edge science. A new ESA facility, based at ESA’s astronomy centre near Madrid, is championing their use for everything from Earth monitoring to fundamental physics.

A Surveyor uses a GNSS device to map urban assets with Galileo and EGNOS. (Image: ESA)

The new ESA Global Navigation Satellite Systems (GNSS) Science Support Centre is based at ESA’s European Space Astronomy Centre, ESAC, near Madrid. Run by ESA’s Galileo Science Office, the GSSC integrates IT and satnav infrastructure to deliver advanced data processing services to the scientific community.

Precisely timed to a few billionths of a second and highly stable, satnav signals can be used as a point of reference for many scientific sectors, including Earth and atmospheric sciences, astronomy, highly precise timing metrology as well as the study of relativity and other fundamental physics topics.

Current satnav infrastructure plans worldwide should see more than 120 satnav satellites in orbit in coming years. This number includes Europe’s own Galileo constellation — offering unique features such as its highly stable passive hydrogen maser atomic clocks, multiple transmission frequencies, robust modulation, wide bandwidth and onboard laser retro-reflectors, which permit exact pinpointing of the satellites’ position in space down to a few tens of centimetres.

“The potential of satnav for science has been recognised for a long time,” explains Javier Ventura-Traveset, Head of ESA’s Galileo Science Office. “The Galileo Science Office was set up in 2016 as a joint initiative between ESA’s Science and Navigation Directorates, coordinating scientific opportunities through interaction with the scientific community and the independent GNSS Science Advisory Committee.

“The opening of the new centre is the next step. It is ESA’s concrete answer to the need expressed by the scientific community for a one-stop-shop to offer researchers long-term GNSS data, products information, results of scientific experiments, plus services to enhance GNSS scientific research and collaboration.

“The future evolution of the centre will be driven by the interaction and feedback received from the scientific community, maximizing synergies with other GNSS data service providers from other institutions and research organization.”

Among the activities to be supported by the new GSSC are big data processing of large amounts of satnav data, crowdsourcing as a means of weather monitoring and a scientific assessment of satnav performance in Antarctica.

It also supports the continuing measurements of general relativity using Galileo satellites 5 and 6 and serves as a global data centre for the International GNSS Service. The long-established Navipedia website, giving technical information on satnav, is also hosted by the GSCC.

One enthusiastic early adopter is ESA’s Navigation Support Office, based at ESA’s ESOC mission control centre in Darmstadt, Germany, lending support to mission teams making use of satnav to steer satellites.

ESA’s GNSS Observation Network (EGON). (Image: ESA)

“The GSSC is a welcome addition to ESA’s activities in the science of satellite navigation,” says Werner Enderle, heading ESOC’s Navigation Support Office. “The GSSC already hosts GNSS products generated by the team at ESOC, including observations from our worldwide EGON GNSS Observation Network and precise satellite orbits generated by their state-of-the-art software. Our two teams look forward to this collaboration continuing for the benefit of ESA and the scientific community.”

The GSSC will roll out access to data, products and services over the coming months.