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Earth’s magnetic field shields it from a constant stream of charged subatomic particles emitted by the sun. As these charged particles approach the earth’s atmosphere, they collide with nitrogen and oxygen atoms and eject photons in visible wavelengths. Near the north and south poles, where magnetic field lines are nearly perpendicular to the earth’s surface, a shimmering, folded curtain of colored light can be seen by human observers. In arctic and subarctic regions, this display is called the aurora borealis, or northern lights. Magnetic turbulence creates movement in the auroral display. The American landscape painter Frederic Edwin Church (1826-1900) based his painting Aurora Borealis on sketches by the explorer Isaac Israel Hayes. In this image Hayes’ steamship United States is frozen in the pack ice of the Kennedy Channel, an ocean strait that separates Ellesmere Island, Canada, from the northwestern coast of Greenland. The only signs of life in this scene are the cabin’s lighted windows and a tiny dogsled returning to the ship. The promontory behind the ship is the coast of Ellesmere Island, and the sharp mountaintop behind the promontory is Church Peak, which was named after the painter by Hayes. On this dark winter day, the only sounds heard by the explorers would have been the wind, the faint barking of sled dogs, and the sudden crack of ice under pressure.
Cole TB. Aurora Borealis Frederic Edwin Church. JAMA. 2015;314(15):1546-1547. doi:10.1001/jama.2014.12035