Satellites to illuminate mystery of northern lights
A team of scientists from Canada and the United States will launch an ambitious project in February to unravel the science behind the shimmering aurora borealis seen in northern skies.
The THEMIS project will launch five satellites into orbit on Feb. 15 to monitor the interaction between charged particles expelled by the sun and the Earth's magnetic field.
When these particles — collectively referred to as the solar wind — interact with the magnetic field they occasionally release energy near the polar regions in aurora substorms. The electron release interacts with molecules in the atmosphere and appears from the night sky as the spectacular displays of the northern lights.
In addition to the five satellites, 20 ground-based observatories, including 16 in Canada, will take digital images and monitor magnetic signatures from these substorms to record the auroras in the night sky.
Most of the observatories will be in communities in the North including Whitehorse; Inuvik, N.W.T.; Sanikiluak, N.W.T.; and Gillam, Man.
The THEMIS project is a joint effort between NASA and the Canadian Space Agency and includes contributions from scientists from the University of Alberta and University of Calgary.
"This is a very exciting moment for us because we are expecting to greatly enhance our understanding of these space disturbances that are both beautiful and powerful," said University of Calgary physics professor Eric Donovan, leader of the Canadian Space Agency-funded component of THEMIS.
NASA scientists aren't as interested in the lights themselves as they are in the energy release that causes them.
That same release of electrons can also lead to unexpected electrical discharges on spacecraft surfaces, which can damage sensitive electronics.
"The worst space storms, the ones that knock-out spacecraft and endanger astronauts, could be just a series of substorms, one after the other," said David Sibeck of NASA's Goddard Space Flight Center in Greenbelt, Md., project scientist for the THEMIS mission.
"Substorms could be the building block of severe space storms."