The three SWARM satellites designed by the European Space Agency (ESA) to measure the Earth’s magnetic field have blasted off from Russia’s cosmodrome Plesetsk atop a Rockot launcher at noon today.
The launch of the trio of spacecraft, named by ESA scientists Alpha, Bravo and Charlie, was closely monitored by controllers at the European Space Operations Centre (ESOC) in Darmstadt, Germany, who confirmed acquiring the signal of the satellites after 1:30pm GMT through ground control stations Kiruna and Svalbard.
The Rockot launcher, with the three satellites inside its payload fairing, lifted off from a launch pad hidden in dense fog, which was covering Russia’s secondary cosmodrome, located some 800km north off Moscow.
The three satellites separated from the Rockot’s Breeze M upper stage about an hour and a half into the flight.
To prevent the three satellites, weighing 473kg each from bumping into each other after separation, while flying some 490km above the Earth’s surface at the speed of about 7km/h, the engineers have equipped them with a special coil-based mechanism designed to push them safely apart.
“It’s a very special moment, it’s little bit as if your child goes away from home for the first time and we have three babies here,” said one of the engineers during a launch event in ESOC that was broadcasted live via the agency’s livestream channel.
Paolo Ferri, Head of Satellite Operations at ESA, explained the hard work is only about to start for the ESOC operators, who will have to power up and check all the satellites’ system and guide them to their operational orbit in the upcoming days.
During this period, the operators will deploy the satellites’ 9m long booms, fitted at the tip with extremely sensitive sensors. The engineers have decided to use the boom in order to protect the measurements from interference from the satellites’ systems.
At the end of the launch and early orbit phase (LEOP), the first two satellite will orbit at the altitude of 460 km, with the third one acquiring measurements from about 70km higher.
The constellation will then embark on its 4-year long mission, measuring the Earth’s magnetic field, trying to help scientists understand why has this field become up to 15 per cent weaker during the last 200 years.
The magnetic field protects our planet from cosmic radiation and charged particles that bombard Earth in solar winds. Without this protective shield, the atmosphere as we know it would not exist, rendering life on Earth virtually impossible.
Swarm’s measurements will also be used to improve the accuracy of navigation systems such as those carried on satellites. This will assist in improving earthquake prediction and increasing the efficiency of drilling for natural resources.
Swarm is ESA’s fourth Earth Explorer mission, following GOCE, SMOS and CryoSat. In its observations of Earth’s magnetic field, Swarm will benefit from the data obtained by ESA’s Cluster scientific mission, launched in 2000 and still operational. Cluster is studying conditions within Earth’s magnetosphere and its interaction with charged particles in the solar wind, using four satellites to map them in 3D over a range of scales.
While Swarm is designed to orbit extremely low, Cluster’s satellites circle the Earth at a distance of 10 000km.