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Signs Of The
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Earth’s protective shield is slowly weakening, allowing harmful solar winds to penetrate the planet’s atmosphere.
Known as the magnetosphere, this shield extends thousands of miles into space and affects everything from global communication to weather patterns. The European Space Agency's Swarm mission aims to map changes to the magnetosphere -- and, after a year in orbit, it's now provided a glimpse into its dynamics.
Swarm is tasked with measuring and untangling the different magnetic signals that stem from Earth’s core, mantle, crust, oceans, ionosphere and magnetosphere. The four-year mission is hoping to eventually provide an insight into various natural processes, from those occurring deep inside the planet through to weather in space caused by solar activity. The three satellites are identical, but to optimise sampling in space and time their orbits are different and change over the course of the mission’s lifeThe magnetosphere protects the Earth from solar radiation. If it weakens dramatically, radiation at ground level would increase with some estimates suggesting that overall exposure to cosmic radiation would double causing more deaths from cancer. The Electric grid collapse from severe solar storms is a major risk. As the magnetic field continues to weaken, scientists are highlighting the importance off-the grid energy systems using renewable energy sources to protect the Earth against a black out. ‘The very highly charged particles can have a deleterious effect on the satellites and astronauts,’ added Dr Mona Kessel, a Magnetosphere discipline scientist at Nasa. The Earth’s climate could also change. A recent Danish study has found that the earth’s weather has been significantly affected by the planet’s magnetic field.They claimed that fluctuations in the number of cosmic rays hitting the atmosphere directly alter the amount of cloud covering the planet. A weakened magnetosphere will also mean that more aurora will be seen on Earth as solar winds hit the atmosphere.
The Swarm constellation also makes it much easier to monitor the changes that occur in the main field produced in the Earth’s core, which protects us from harmful charged cosmic particles. ‘Our magnetic field is largely generated by Earth’s outer core,’ said Gauthier Hulot, one of the lead proposers of the Swarm mission. ‘The constellation provides detail on the way the field is changing and thereby weakening our protective shield.’ ‘This is what will ultimately make it possible to predict the way this field will evolve over the next decades.’ The Swarm satellites will be in orbit for another three years at least. These results will be presented at the 26th General Assembly of the International Union of Geodesy and Geophysics on 22 June to 2 July in Prague, Czech Republic
