It was interesting how they dealt with this for the Apollo missions.<p>Shortly before the launches Operation Starfish Prime took place and one hope was that detonating nuclear bombs in the upper atmosphere might deform the Van Allen belts or indeed that the extra energy might displace them entirely.<p>However, it actually strengthened the radiation belt, fortunately it dissipated relatively quickly and it was safe for the lunar missions.<p><a href="https://thewire.in/the-sciences/apollo-11-van-allen-radiation-belts-translunar-injection" rel="nofollow">https://thewire.in/the-sciences/apollo-11-van-allen-radiatio...</a>
These belts are created (at least mostly) by Earth's magnetic field capturing or deflecting incident radiation, which therefore shields Earth's surface from the radiation and (I believe) protects life.<p>Earth's magnetic field isn't stable with time and has (geologically) frequent pole reversals. We don't have a great idea of how long this process takes, whether it is near-instantaneous or takes hundreds of years (or perhaps longer?). The poles are currently 'wandering' relatively fast and some geophysicists think this may be a sign of a pole reversal to come.<p>I wonder about how the Van Allen belts fair during a pole reversal, and if for some time interval the amount of incoming radiation on the Earth's surface is much greater, perhaps at dangerous levels.<p>Earth also has a much stronger geomagnetic field than other rocky planets because it has a solid iron-nickel inner core that rotates inside of a liquid iron-nickel outer core, inducing the magnetic field (the so-called 'geodynamo'. If the resulting Van Allen belt is indeed a safeguard to the development of life on Earth, it may be part of the reason that Earth is unique in life development versus its neighbors.
Also related: <a href="https://en.wikipedia.org/wiki/South_Atlantic_Anomaly" rel="nofollow">https://en.wikipedia.org/wiki/South_Atlantic_Anomaly</a><p>Our low-Earth orbit satellites go a bit berserk each time they pass through the SAA. Star trackers used for orientation estimation pick up lots of pixel snow.
Couple of nice references:<p>Observation of high intensity radiation by satellites 1958 Alpha and Gamma J A Van Allen Journal of Jet Propulsion
<a href="http://www-pw.physics.uiowa.edu/ProfVanAllen/1958_VanAllen_ObservationOfHighIntensityRadiationBySatellites1958AlphaAndGamma_JPL_28_588-592.pdf" rel="nofollow">http://www-pw.physics.uiowa.edu/ProfVanAllen/1958_VanAllen_O...</a><p>Apollo Experience Report - Protection from Radiation
Technical Note TN D-7080, March 1973
<a href="https://www.hq.nasa.gov/alsj/tnD7080RadProtect.html" rel="nofollow">https://www.hq.nasa.gov/alsj/tnD7080RadProtect.html</a>
The "Proposed Removal" is interesting. I also read elsewhere that it was thought nuclear blasts could clear holes for astronauts to travel through.