Feb. 16, 2007 — NASA is set to launch a spacecraft carrying five satellites on a mission to unveil the secrets of the origin of the aurora borealis.
The two-year mission, dubbed THEMIS — an acronym for Time History of Events and Macroscale Interactions during Substorms — will be coordinated by a team from the University of California at Berkeley.
Once deployed, the satellites will align below North America every four days to observe the formation of the aurora borealis, a bright play of lights in the night sky above the polar area, commonly known as the northern lights. On the ground, stations in Alaska and in Canada will photograph the multicolored phenomena.
"This is a challenging project that will replace old myths with scientific explanations for the lights' visible evidence of the earth's magnetosphere protecting us from the fatal effects of the solar wind," said Frank Snow, the National Aeronautics and Space Administration's THEMIS mission manager.
Scientists hope that the five satellites operating jointly will be able to identify the precise location of where the aurora borealis starts.
Scientists currently believe that the lights are caused by solar winds that are deformed when they reach the earth's magnetic field, forming a tail of sorts when caught in the wind.
The energy stored in this 'tail' is released sporadically, causing substorms at the equator and then spreading out towards the north and south poles, where it produces aurora borealis phenomenon.
While scientists have a good idea how this works, they have been unable to explain where in the magnetosphere the energy of solar wind transforms into the spectacular phenomenon of lights.
