THEMIS Spacecraft Fleet Thwarts Magnetic Shield Leaks Theory

A new study supported by NASA and the National Science Foundation has reached more thorough results related to the way solar storms affect the Earth's magnetic shields, making the old views inaccurate. Depending on the alignment with the Sun's magnetic field, our own develops two huge holes which allow large amounts of solar particles to breach it. Based on some characteristics of the field, researchers can now determine the strength of the upcoming solar storms.

The magnetic field of the Earth behaves as a protective wall against the constant pummeling of the Sun's particle jets thrown towards us. Given that the ions and electrons of the jets are electrically charged, the planetary field can successfully respond to their charge and deflect most of them. Previous theories stated that when the Sun's field was facing a direction opposed to that of ours, giant doors would open for the particles to pass unscathed, and when the directions were similar, the gates would shut.

 

The new research, based on the results of NASA's Time History of Events and Macroscale Interactions during Substorms mission (THEMIS), comprised of a fleet of five spacecraft that measured the size of the leak, indicated that the opposite is, in fact, valid. "Twenty times more solar particles cross the Earth's leaky magnetic shield when the sun's magnetic field is aligned with that of the Earth compared to when the two magnetic fields are oppositely directed," explained Marit Oieroset from the University of California, Berkeley, quoted by Scientific Blogging.

 

"The discovery overturns a long-standing belief about how and when most of the solar particles penetrate Earth's magnetic field, and could be used to predict when solar storms will be severe. Based on these results, we expect more severe storms during the upcoming solar cycle," shared Vassilis Angelopoulos of the University of California, Los Angeles, Principal THEMIS Investigator.