Plasma Shield Protects Earth From Solar Storm

Plasma Shield Protects Earth From Solar Storm

Scientists at MIT and NASA have discovered that the Earth’s plasma shield along with its magnetosphere can wade off the harmful effects of a solar storm. For years scientists have known of its existence, but were unsure of what purpose it served. This was because the Earth’s magnetosphere was already known to protect the planet from any high energy solar activity. A process called ‘magnetic reconnection,’ occurs when the Earth’s magnetosphere comes into contact with the magnetic field of the sun. Solar storms and space weather in general has an important effect on many aspects of life on Earth.

Such storms which are also known as geomagnetic storms arise from solar flares and coronal mass ejections on the sun’s surface. They cause a blast of highly charged particles into space. Unless their course is checked they can cause severe damage on Earth. Typically it is the magnetosphere that protects the earth from these particles. This is especially true about coronal mass ejections which is a fairly common occurrence. However, scientists have now proven that when large and more intense storms occur, during magnetic reconnection, a body of plasma works in conjunction with the magnetosphere to slow down these particles and protect the Earth from the more severe effects of such storms.

During magnetic reconnection, a portion of the Earth’s magnetic field is debilitated as highly charged particles collide with the earth’s magnetosphere. Powerful electric currents are generated and they flow in the trajectory of the Earth’s magnetic field. These currents have interfered with various power grids before causing massive blackouts. In addition, geomagnetic storms disrupt high altitude flights, and operations in space. This can include the disruption and damage of satellites and the safety of our astronauts on space stations. Scientists have now been able to pinpoint why a lot of the adverse effects of this phenomenon have been curtailed. They attribute this to the role the plasma shield has played as it protects the Earth from such life threatening situations caused by a solar storm.

This finding can now help to predict the severity of such geomagnetic storms. For more than a decade at the Haystack Observatory, scientists have been studying the Earth’s plasma shield which occurs as a plume phenomenon. Recently this data has been combined and verified with studies conducted in outer space where this phenomenon could be observed directly. Instead of just mapping its existence with radio wave signals, scientists observed that the plasma field moved much like that of a stream or river. It’s functions more or less like the gulf stream or any other weather redistribution system.

Much of these findings were solidified during an extreme solar storm in January 2013.  This layer was verified to consist of hydrogen particles that were ionized because of the ultraviolet rays of the sun. The NASA Themis spacecraft has conducted extensive studies of the plume like field by measuring its density in different regions around the Earth. In essence, during an extreme solar storm the plasma shied of the Earth slows down the process of magnetic reconnection, which is a process that protects much of life as we know it. This scientific finding can help us to better understand space weather and to predict its effects on Earth more accurately.

By Unni K. Nair


MIT News

ABC Science