Kristian Birkeland

Kristian Birkeland (December 13, 1867 - June 15, 1917) was born in Christiania (Oslo today) and wrote his first scientific paper at the age of 18. He organized several expeditions to Norway's high-latitude regions where he established a network of observatories under the auroral regions to collect magnetic field data. The results of the Norwegian Polar Expedition conducted from 1899 to 1900 contained the first determination of the global pattern of electric currents in the polar region from ground magnetic field measurements. The discovery of X-rays inspired Birkeland to develop vacuum chambers to study the influence of cathode rays on magnets. An example of one of his experiments is depicted on the left front of the bank note. It shows a magnetized terrella, simulating the Earth, suspended in an evacuated box. Birkeland noticed that an electron beam directed toward the terrella was guided toward the magnetic poles and produced rings of light around the poles and concluded that the aurora could be produced in a similar way. He developed a theory in which energetic electrons were ejected from sunspots on the solar surface, directed to the Earth, and guided to the Earth's polar regions by the geomagnetic field where they produced the visible aurora. Birkeland was nominated for the Nobel Prize no less than seven times.

Related Topics:
December 13 - 1867 - June 15 - 1917 - Christiania - Oslo - Magnetic field - Norwegian Polar Expedition - X-rays - Terrella - Earth - Polar regions - Nobel Prize

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The scale of Birkeland's research enterprises was such that the time-honored matter of funding became an overwhelming obstacle. Recognizing that technological invention could bring wealth, he developed an electromagnetic cannon. In 1900, he obtained patents on what we now call an electromagnetic-rail-gun and, with some investors, formed a firearms company. The rail-gun worked, except the high muzzle velocities he predicted (600 m/s) were not produced. The most he could get from his largest machine was 100 m/s, corresponding to a disappointing projectile range of only 1 km. So he renamed the device an aerial torpedo and arranged a demonstration with the express aim of selling the company. At the demonstration, one of the coils in the rail-gun shorted and produced a sensational inductive arc complete with noise, flame, and smoke. This was the first failure of any of the launchers that Birkeland had built. It could easily have been repaired and another demonstration organized.

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However, fate intervened in the form of an engineer named Sam Eyde.

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At a dinner party only one week later, Eyde told Birkeland that there was an industrial need for the biggest flash of lightning that can be brought down to Earth in order to make artificial fertilizer. Birkeland's climactic reply was: I have it! There were no more attempts to sell the firearms company, and he worked with Eyde only long enough to build a plasma arc device for the nitrogen fixation process. Birkeland then enjoyed adequate funding for his only real interest: research.

Related Topics:
Artificial fertilizer - Nitrogen fixation process - Research

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In 1913, Birkeland may have been the first to predict that space is not only a plasma, but also contains "dark matter". He wrote: "It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. We have assumed that each stellar system in evolutions throws off electric corpuscles into space. It does not seem unreasonable therefore to think that the greater part of the material masses in the universe is found, not in the solar systems or nebulae, but in "empty" space. (Ref. See notes)

Related Topics:
Plasma - Dark matter

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In 1916, Birkeland was probably the first person to successful predict that in the Solar Wind, "From a physical point of view it is most probable that solar rays are neither exclusively negative nor positive rays, but of both kinds"; in other words, the Solar Wind consists of both negative electrons and positive ions (Ref. See notes)

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