Protection for the Earth

Solar storm created third Van Allen belt

The solar storm in May - the most violent since 2003 - gave our Earth an additional, third Van Allen belt.

(Bild: JHUAPL/LASP)

The solar storm in May - the most violent since 2003 - has given our Earth an additional, third Van Allen Belt. This is shown by data transmitted to Earth by NASA's CIRBE (Colorado Inner Radiation Belt Experiment) satellite.

The new belt created by the solar storm lies between the permanently existing inner and outer Van Allen radiation belts (see image above), reports the US space agency NASA.

The Earth is normally orbited by two Van Allen radiation belts. The inner of the two begins about 1600 kilometers above the Earth's surface and extends to an altitude of 12,800 kilometers. The outer one extends at an altitude of approximately 19,300 to 40,200 kilometers. The Van Allen belts were discovered in 1958 by the NASA space probe "Explorer 1".

This radiation ring consists of captured particles originating from the sun. Astronauts flying to the moon and back therefore have to cross both radiation belts twice, once on the way there and once on the way back.

Particles from the outer Van Allen belt
Satellites have already detected such an intermediate ring of extremely fast electrons once - after a solar storm in 2012. Analyses at the time showed that these particles originally came from the outer Van Allen belt, but were swept inwards by the force of the solar storm and collected there to form a new, third ring.

What is a cubesat?

Cubesats are small satellites whose basic unit is roughly cube-shaped (hence "cube"). This specification for low-cost nanosatellites developed in the USA was first used in space travel in 2004 and has since established itself as the industry standard. They are carried in a special launch device as a secondary payload during satellite launches.

The previously outer ring becomes a store for high-energy particles. This configuration is then stable until another powerful solar wind blast restores the original configuration. 

Of great importance for mankind
The Van Allen belts are named after their discoverer, the US astrophysicist and space pioneer James Alfred Van Allen. They are of great importance to modern society, which is dependent on numerous space-based technologies (e.g. GPS).

They are affected by solar storms and space weather and can inflate dramatically. When this happens, they can pose a threat to communications and GPS satellites.

NASA's CIRBE satellite, a so-called cubesat, investigates the inner radiation belt of the Earth's magnetosphere and is intended to provide new insights into the high-energy particles that could disrupt satellites and endanger astronauts, for example during a spacewalk.