Space science data handling has two aspects. First, it requires the setting up of a network of tracking and telemetry stations that can receive signals from spacecraft and transmit commands to them. Second, it requires a central facility that processes and manages the information from the tracking network.
The facilities at the Centre, initially designated the European Space Data Acquisition Centre (ESDAC), essentially comprised a large mainframe computer or computers, that were made available both to its in-house staff and to visiting scientists and fellows who wished to use them to analyse and study the recovered data. ESDAC was later renamed ESOC, the European Space Operations Centre. ESOC is located in Darmstadt, Germany, and after the Bannier Report, it additionally gained overall executive authority for spacecraft operation. ESOC's director also became responsible for ESRANGE and for ESTRACK.
Over the past fifty years, ESTRACK, ESA's tracking station network, has comprised a variety of antennas located around the world, including Australia and Argentina, and in remote locations, including the Falkland Islands and Spitzbergen. It originally consisted of four stations operating in the VHF radio band and situated in Redu, Belgium, Fairbanks, Alaska, USA, Spitsbergen, Norway, and the Falkland Islands.
Throughout its history, ESTRACK stations have enabled real-time commanding and control and downlinking of scientific data from missions in all types of orbits around Earth as well as from missions to the Moon, to the Sun-Earth Lagrange points and to interplanetary destinations like Mars, Venus and, of course, Rosetta’s comet.
Today, the core network has been consolidated into seven stations, including three, technically sophisticated 35 m-diameter deep space antennas at New Norcia, Western Australia, Cebreros, Spain, and Malargüe, Argentina, plus a network operations centre located at ESOC, staffed around the clock.
Additional stations are utilised for tracking ESA missions through partnership agreements or on a commercial basis. A long-term cross-support agreement with NASA means that ESTRACK stations are interlinked with those of NASA’s Deep Space Network (DSN) and each routinely supports the other’s spacecraft.
European stations also support missions from the Russian, Japanese and Chinese space agencies, as well as assisting other partners.
“International cooperation is important. Big goals can only be achieved together,” says Paolo Ferri, who was responsible for interplanetary mission operations until 2006 and succeeded Manfred Warhaut as ESA’s Head of Mission Operations in 2013.
ESA's tracking station network is a global system of ground stations providing links between satellites in orbit and ESOC, the European Space Operations Centre, Darmstadt, Germany. The core Estrack network comprises seven stations in seven countries.
The essential task of all ESA ground tracking stations is to communicate with spacecraft, transmitting commands and receiving scientific data and spacecraft status information.
Our technically advanced stations can track spacecraft almost anywhere – circling Earth, watching the Sun, orbiting at the scientifically crucial Sun-Earth Lagrange points or voyaging deep into our Solar System.
The 15 m-diameter stations, using high frequencies and data rates, were established starting in 1975. The first of these was located at Villafranca del Castillo, Spain, for the International Ultraviolet Explorer mission (and since then, the original Villafranca location has expanded to become ESAC, the European Space Astronomy Centre, ESA’s major establishment in Spain).
In a typical year, the Estrack network provides over 45 000 hours of tracking support to 20 or more missions, with an enviable service availability rate above 99%.
ESOC’s engineers are now developing and testing laser communications to support the next generation of missions.
Read more on '50 years of ESA's Mission Control'