Kristian Birkeland, the first space scientist


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  • Giuseppe Bonacina
  • (bonacina1940@gmail.com)
  •  XII International Crimean Conference
  • “Cosmos and the Biosphere”
  • Alushta, Crimea, October 2-6, 2017
  • Kristiana (now Oslo, Norway), 1867
  • - Tokyo (Japan), 1917
  • ■ he was the first to plausibly address the polsr aurorae to electrical charged particles of solar origin
  • ■ Birkeland organized three expeditions in arctic regions for a direct observation and registration of the polar aurorae (northern lights)
  • ■ he realized an original apparatus for the silumations of aurorae in laboratory (terrella)
  • ■ the Birkeland “solar” theory was disputed in 50s and 60s by the English geophysical Sydney Chapman, who developed mathematical descriptions of current systems contained completely within the Earth ionosphere
  • ■ direct evidence of the Birkeland theory was established In the mid-sixties with the magnetometers on board of artificial satellites in the upper atmosphere.
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  • three expeditions in arctic regions
  • third expedition, 1902-1903
  • second expedition, September 1899 – April 1900
  • ■ it was a «failure» for adverse weather conditions and a lack of experience
  • ■ the results of the second expedition and the preliminary theory of «solar» origin of the polar aurorae are reported in the book of K. Birkeland Expedition Norvegienne 1899-1900 (Norway, 1901)
  • 1. Kaafjord (69° 56’ N), Norway
  • 2. Dyrafjord (66° 15’ N), Iceland
  • 3. Axeløen (77° 41’ N), Svalbord Archipelago
  • 4. Matotchkin Schar (73° 16’ N), Novaya Zemlya, Russia
  • ■ 4 stations in the auroral ring
  • ■ results of the third expedition and of the laboratory experiments are reported in the book of K. Birkeland The Norvwegian Aurora Polaris Expedition 1902-1903 - On the cause of magnetic storms and the origin of terrestrial magnetism
  • (Norway, 1908)
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  • auroral ring
  • aligned electric
  • currents (vertical)
  • auroral
  • electrojet (horizontal)
  • ■ a glass chamber with a high vacuum containing a source of cathode rays, simulating the Sun, and a magnetized metallic sphere (terrella), «piccola Terra», small Earth) simulating the Earth
  • ■ diameter 4000 km
  • ■ latitude 60° - 70° N and S
  • ■ height 100-150 km (ionosphere)
  • ■ light production from excited oxigen and nitrogen molucules in the air
  • ■ planet conditions for aurorae: a magnetic field and a gaseous atmosphere (Earth, Jupiter, Saturn and Uranus)
  • Birkeland’s original digram explaining the origin of polar aurorae from solar wind
  • ■ more frequent about equinoxes
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  • current polar aurorae mechanism
  • solar wind
  • electric currents in the Earth magnetosphere
  • Alv Egeland, William J. Burke
  • Kristian Birkeland - The first space scientist
  • Springer, 2005
  • Norwegian 200 kroner banknote dedicated to Kristian Birkeland
  • ■ recurrents aurorae events: (about 27 days): from coronal holes
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