To better understand the sun's magnetic fields, NASA has built a trippy, moving computer model mapping the star's magnetic field lines.
The model shows both closed magnetic field lines (these are colored white-gold) and open magnetic field lines, which project out into space (these are colored green or pink depending on their polarity). Bright spots appear when closed magnetic field lines bump into each other, causing explosions.
Studying these dancing, dynamic magnetic fields is crucial in part because these explosions can cause solar storms, like solar flares or coronal mass ejections. Many within the scientific community believe that solar storms could pose a significant threat to Earth. Aside from disrupting space travel and satellite orbits, it's possible that a big enough storm could disrupt our own planet's geomagnetic field, which would destroy power grids and could leave us in the dark for months at a time.
It sounds like science fiction, but it's happened before—the last such incident was in 1859. Called the Carrington Event, it started fires and knocked out telegraph networks. But since we rely infinitely more on electricity in the present day, a massive solar storm would disrupt life on a much, much larger scale.
FOIA'ed documents released a few months ago revealed that the US Geological Survey had requested a budget increase to map Earth's geomagnetic field lines and do research that could help us protect ourselves in the event of a massive storm. Luckily, it appears the budget proposal has since been passed and the USGS got the $1.7 million it requested.
Maybe we can feel a little bit safer.