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Satellites to observe reconnection of magnetic fields

Fabian SchmidtMarch 13, 2015

Four new NASA satellites have been launched to find out what happens when magnetic fields disconnect briefly from earth and then reconnect in another direction. On the sun, the same phenomenon triggers sunspots.

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MMS Spacecraft in Earth’s Orbit (Photo: NASA)
MMS satellites are trying to solve the mystery behind magnetic reconnectionImage: NASA

On Thursday at 10:44 p.m. EST, an Atlas-V421 rocket took off to bring four new NASA observation satellites into orbit. They arrived less than two hours later at their destination.

Together, they form the Magnetospheric Multiscale (MMS) experiment - a system to observe a phenomenon called "magnetic reconnection" in great detail.

Explosive force

This means the following: When the magnetism of planets or suns and other stars moves, magnetic fields at the edges of the poles can briefly separate and reconnect in another direction. At the moment of the separation, explosive ejections of particles occur into space - almost at the speed of light. The phenomenon is well known from the sun as coronal mass ejections, visible from earth as sun-spots.

But the phenomenon of magnetic reconnection exists also on earth, albeit in a much weaker form. And this is, what the satellites are trying to detect at heights of between 70,811 and 152,888 kilometers.

"We've never had the opportunity to study this fundamental process in such detail," said Jim Burch. He is the principal investigator for the MMS instrument suite science team at the Southwest Research Institute in San Antonio, Texas.

USA NASA Pressemitteilung Spacecraft in Earth’s Orbit EINSCHRÄNKUNG
The Atlas V 421 rocket successfully delivered all four satellites into their orbit.Image: NASA

Sunspots

The results of the research may also be useful for applied engineering: In prototype nuclear fusion reactors, the same phenomenon takes place. The scientists hope that the data from the satellites helps explain why this leads to a drop of temperatures in fusion chambers.

And it could help to predict coronal mass ejections on the sun earlier than is possible now. Heavy sunspot activity can disrupt communication installations or radio transmissions on earth. Entire power grids have even collapsed as a result of the electromagnetic impact of sun storms.

Also, astronomers are hoping the MMS will provide answers to phenomena such as black holes or neutron stars.

To collect the data, the satellites will fly in a pyramid-shaped formation. Each of them is equipped with 25 Sensors. The measurements are scheduled to start in September. The entire mission is supposed to run for two years.