An Important Step in the Advance of Space Weather Research
Although the earth’s Van Allen Radiation Belts were discovered by James Van Allen in 1958, not much was knows about these important radiation protective belts circling the earth.
In case you are wondering, James Alfred Van Allen (September 7, 1914 – August 9, 2006), was a space scientists and researcher at the University of Iowa. He was the man who was instrumental in establishing field of study of magnetospheric conditions in space and performed extensive magnetospheric research related to space weather conditions surrounding the earth.
But it wasn’t until August 2012, that NASA launched the Van Allen Probes which have been closely observing and monitoring the Van Allen Belts. Withing only days of the launch the probes provided detailed pictures of the region and revealed a third belt which was unknown to science till then.
The new Van Allen ring of radiation was observed during high solar radiation levels and persisted for nearly a month. This proved even further that the Van Allen Belts swell as they absorb solar radiation, helping scientists map out the mysterious Van Allen Belt region.
The radiation belts are doughnut-shaped and encircle the Earth with polar or cusp regions near the poles of the earth. These belts attract high-energy particles, mostly electrons and ions, and trap them there by the earth’s magnetic field. Within minutes or hours after electrons are trapped in these belts, they can be accelerated to close to the speed of light and can swell to 100 times their normal size.
However the August 2012 discovered ring, developed between the inner and the outer ring. This new, middle ring was narrow, and its electrons had energies between 4 and 7.5 mega-electron-volts which is the same energy of electrons in the outer Van Allen belt during an acceleration event or space weather event.
This radiation can also be other subatomic particles of light of various wavelengths which cause conditions in the near earth space called “space weather”.
Space weather is analogous to the atmospheric weather conditions on Earth and can affect the performance and reliability of all forms of technologies on earth, as well as pose threat to weather patterns on earth and tectonic plate movements. This type of space weather condition also poses considerable threat to astronauts in space, aircraft passengers, and spacecraft in space.
Understanding how and why this new radiation belt was formed can help us to better protect our spacecrafts in space from radiation damage.
The inner Van Allen belt is located between one to eight thousand miles above the Earth’s equator. The outer belt extends from about 12 to 25 thousand miles. The third belt is located between these two belts.
The isolated new Van Allen Radiation ring has not yet been named and unless you mind very much, I don’t see the rush in name it or just leaving its name as the third Van Allen Radiation Belt!
CREDIT: NASA Van Allen Probes