Newly Discovered Van Allen Belt of Radiation Around Earth [Nature]

My article in Nature, Ephemeral Third Ring of Radiation Makes Appearance Around Earth, discusses how twin spacecraft studying the Van Allen radiation belt overturned a fifty year old model: Instead of seeing two rings of high-energy particles circling the Earth, an unexpected third ring has been found.

Earth's third Van Allen Belt
Earth’s third Van Allen Belt. Credit: NASA Van Allen Probes/Goddard Space Flight Center

From the article:

…telescopes on the probes revealed the emergence of an additional, narrow belt of charged particles sandwiched between the inner ring and a now highly eroded outer ring. “It was so unexpected that we thought there was something wrong with the instrument,” says Daniel Baker, a space physicist at the University of Colorado in Boulder.


The findings, which are reported today in Science, demonstrate that solar outbursts are indeed a strong driving force behind the structure of the belts and that similar activity might be common, especially now, near the peak of the 11-year solar cycle, Baker says. Nonetheless, he adds, details about the dramatic reshaping of the outer belt and the location of the month-long middle ring cannot be explained by current theory.

Read the rest of the Nature article for more information about the third Van Allen Belt and the structure of these belts.