Plasma Shield Guarding Earth From Solar Storm
The Earth's magnetic field which is also known as magnetosphere, stretches from the planet's core out into space only to act as a shield to protect the Earth from the high-energy solar activity, a new research has found.
However, researchers warned that when this field came into contact with sun's magnetic field, powerful electrical currents from the sun could stream into our atmosphere. This could whip up geomagnetic storms and space weather phenomenon affecting high-altitude aircrafts and even astronauts on the International Space Station.
"The Earth's magnetic field protects life on the surface from the full impact of these solar outbursts," said John Foster, associate director of MIT's Haystack Observatory in a press release. "Reconnection strips away some of our magnetic shield and lets energy leak in, giving us large, violent storms. These plasmas get pulled into space and slow down the reconnection process, so the impact of the sun on the Earth is less violent."
Scientists have been studying plasma plume phenomena using a ground-based technique called GPS-TEC for the last ten years. This involves analyzing radio signals transmitted from GPS satellites to more than 1,000 receivers on the ground.
"This higher-density, cold plasma changes about every plasma physics process it comes in contact with," Foster added. "It slows down reconnection, and it can contribute to the generation of waves that, in turn, accelerate particles in other parts of the magnetosphere. So it's a recirculation process, and really fascinating."
Other experts pointed that although others have observed magnetic reconnection, they did not look at data closer to Earth to understand this connection.
"I believe this group was very creative and ingenious to use these methods to infer how plasma plumes affect magnetic reconnection," said Tony Mannucci, supervisor of the Ionospheric and Atmospheric Remote Sensing Group at NASA's Jet Propulsion Laboratory, who was not involved in the research, in the press release. "This discovery of the direct connection between a plasma plume and the magnetic shield surrounding Earth means that a new set of ground-based observations can be used to infer what is occurring deep in space, allowing us to understand and possibly forecast the implications of solar storms."
The finding of the study will be published in this week's issue of Science.