ROBOT SWARM positions itself over EARTH ... to probe our magnetic field
For the poles, they are a-changin'
The European Space Agency has successfully deployed its trio of mapping satellites, dubbed Swarm, and is ready to start some serious scanning of the Earth's changing magnetic fields.
The Swarm payload was launched from the Plesetsk cosmodrome in Northern Russia on Friday evening and has now split into its three constituent satellites. Two will orbit the Earth in tandem on a polar path at an altitude of 450km, while the third will fly above them at 530km once the the launch and early orbit phase (LEOP) is complete.
"We've had a trouble-free LEOP and the satellites are performing beyond expectation," said flight operations director Pier Paolo Emanuelli in a statement. "We're looking forward to an excellent mission."
The ESA team is now focused on starting up the Swarm's main telemetry systems in preparation for magnetic mapping operations. The mission is going to help scientists understand the strange phenomenon of magnetic-pole shifts that the Earth is currently undergoing.
While early explorers thought the magnetic poles on our planet were fixed, geological evidence shows that they change roughly every 250,000 years – but as far as geoscientists can tell, they haven't shifted significantly in over double that time period since their last big switchover.
But NASA reports that the Earth's magnetic North Pole has been moving further north at a rate of 40 miles per year, four times the speed it displayed a century ago. At the same time, the magnetic field is weakening slightly.
The Earth's magnetic field is a key element in protecting the fragile life forms on the surface from dangerous solar radiation. While you would expect this protection to lessen somewhat during a shift in poles, it's nothing too much to worry about, Todd Hoeksema, a solar physicist at Stanford's Wilcox Solar Observatory told The Reg.
"The same systems that are vulnerable now, such as power systems, would face increased risks, but your radio and telephone are still going to work. And this isn't something that happens overnight – we'd have a warning," he said.
Hoeksema is something of an expert in the field and has been mapping the Sun's magnetic pole shift, which has been ongoing for the last year. But he told us that the Earth's poles are expected to shift from a binary pole system to one with four poles. This will pose something of a problem for compass makers, but life as we know it will still carry on just fine, he said.
ESA's Swarm mission will now spend the next four years mapping our magnetosphere, how it reacts with solar winds, and how the rate of change is proceeding. A full magnetic shift should take a thousand years or so, so no need to panic yet. ®