Aurora secrets probed
Joint Norwegian, American, and Japanese research looks into the northern lights
M. Michael Brady
Asker, Norway
The aurora, the colorful displays of light in the sky seen at high latitudes, have been studied since antiquity. The first scientific theory of its origin was put forth by Norwegian physicist Kristian Birkeland (1867-1917) in a book published in 1908 [The Norwegian Aurora Polaris Expedition 1902-1903, out-of-print; full text online at archive.org/details/norwegianaurorap01chririch]. It occurs in the cusp, a region in space around each pole, in which the Earth’s magnetic field dips inward, channeling charged particles from the Sun earthward, where they interact in the upper atmosphere to produce the aurora. Birkeland’s theory was disputed by traditional scientists of his time but in 1967 was proven correct by measurements made by instruments on an orbiting earth observation satellite.
Today, the aurora and the ways it behaves are part of everyday scientific knowledge, grouped in a field of study known as space weather. And there’s a continuously updated monitor of space weather accessible online at www.spaceweather.com. Yet scientific understanding of the interactions within the cusps is not yet sufficient to permit forecasting of space weather, similar to the meteorological forecasting of the weather on Earth.
That may change soon. Last April, the USA, Japan, and Norway agreed to initiate The Grand Challenge Initiative (GCI) aimed at advancing the scientific understanding of the interactions within the cusps. Four academic institutions are involved: the University of Oslo, the University of Alaska, the University of Iowa, and Dartmouth College. The data acquired by the participating agencies—the National Aeronautics and Space Administration (NASA), the Japan Aerospace Exploration Agency (JAXA), and the Svalbard Integrated Arctic Earth Observation System (SIOS)—will be shared in a common database, hopefully prompting synergy leading to scientific results beyond those achievable by individual projects of the participating countries. From December 2017 through December 2019, there will be 11 sounding rocket missions, in conjunction with ground-based scientific instrument data. For further details on GCI, visit its website at www.grandchallenge.no.
This article originally appeared in the Sept. 22, 2017, issue of The Norwegian American. To subscribe, visit SUBSCRIBE or call us at (206) 784-4617.
