I just found this article while researching the Van Allen belts.
"The kicker? It's actually saving us.
Forget the Karman line, there's a human-made space barrier to wonder about, first observed by NASA in 2017. The mysterious zone of anthropogenic space weather is caused by specific kinds of radio waves that we've been blasting into the atmosphere for decades, but experts say the expanding band actually helps protect humankind from dangerous space radiation."