Kristian Olaf Birkeland (13 December 1867 – 15 June 1917) was a Norwegian scientist. He is best remembered as the person who first elucidated the nature of the Aurora borealis. In order to fund his research on the aurorae, he invented the electromagnetic cannon and the Birkeland-Eyde process of fixing nitrogen from the air. Birkeland was nominated for the Nobel Prize seven times.[1][2]
Life and death
Birkeland was born in Christiania (Oslo today) and wrote his first scientific paper at the age of 18.
Birkeland got married in May 1905 with Ida Charlotte Hammer, they have no kid and due to Kristian's work, they finally divorced in 1911.[3]
Suffering from severe paranoia due to his use of Veronal as a sleeping aid, he died under mysterious circumstances in his room in the Hotel Seiyoken in Tokyo while visiting colleagues at the University of Tokyo. A post-mortem revealed that Birkeland had taken 10g of veronal the night he died, instead of the 0.5g recommended. The time of death was estimated at 7am on 15 June, 1917.[1] Some authors have claimed that he committed suicide[4].
Research
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 magnets on cathode rays. Birkeland noticed that an electron beam directed toward a magnetised 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.
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 and, with some investors, formed a firearms company. The coil-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 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.
However, fate intervened in the form of an engineer named Sam Eyde. 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. The pair worked to develop the prototype furnace into a design that was economically viable for large-scale manufacture. The resulting company, Norsk Hydro, hugely enriched Norway and Birkeland then enjoyed adequate funding for his only real interest: research.
The fact that Birkeland joined with Eyde as a business partner, appears to have been one of the reasons why Birkeland was unsuccessful in being awarded the Nobel Prize for his idea. Eyde wanted to be nominated along with Birkeland, however the Nobel Prize is designed to recognise the original idea, not any commercial applications. This resulted in a possibly contentious nomination, and this combined with the fact that at that time relations between Sweden and Norway were delicate, meant that he wasn't nominated by the committee.
In 1913, Birkeland may have been the first to predict that plasma was ubiquitous in space. 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."[5]
In 1916, Birkeland was probably the first person to successfully predict that the solar wind behaves as do all charged particles in an electric field, "From a physical point of view it is most probable that solar rays are neither exclusively negative nor positive rays, but of both kinds"[6] In other words, the Solar Wind consists of both negative electrons and positive ions.
Kristian Birkeland and his terrella experiment
Birkeland suggested that polar electric currents -- today referred to as auroral electrojets—were connected to a system of currents that flowed along geomagnetic field lines into and away from the polar region. He provided a diagram of field-aligned currents in his book, "The Norwegian Aurora Polaris Expedition 1902-1903". This diagram is reproduced on the back of the bank note in the lower right corner. This book contains chapters on magnetic storms on the Earth and their relationship to the Sun, the origin of the Sun itself, Halley's comet, and the rings of Saturn. Birkeland's vision of field-aligned currents became the source of a controversy that continued for a quarter of a century, because their existence could not be confirmed from ground-based measurements alone.
The absolute proof of Birkeland's field-aligned currents could only come from observations made above the ionosphere with satellites. A magnetometer onboard a U.S. Navy navigation satellite launched in 1963 observed magnetic disturbances on nearly every pass over the high-latitude regions of the Earth.
The magnetic disturbances were originally interpreted as hydromagnetic waves, but it was soon realized that they were due to field-aligned or Birkeland currents. The first complete map of the statistical location of Birkeland currents in the Earth's polar region was developed in 1974 by A.J. Zmuda and J.C. Armstrong and refined in 1976 by T. Iijima[7] and T.A. Potemra[8][9][10]
Legacy
An example of one of his experiments is depicted on the left front of the Norwegian 200 krones note it shows a magnetized terrella, simulating the Earth and mars suspended in an evacuated box. Birkeland's face appears a second time in a watermark in the blank space above the drawing of the Terrella, and his rudimentary magnetosphere appears on the back but is only visible under ultraviolet light. The ring encircling the magnetic pole depicted on the back of the bank note is similar to the patterns predicted by Birkeland and shown more recently by satellites.
Quotes
- 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. — Kristian Birkeland [11][citation needed]
- A very few lonely pioneers make their way to high places never before visited . . . they create the living conditions of mankind and the majority are living on their work. — Kristian Birkeland [12][citation needed]
References
- ^ a b Lucy Jago (2001). The Northern Lights. Knopf. ISBN 0375409807.
- ^ Potemra, T. A. (1997). "The contributions of Kristian Birkeland to space physics". Geomagnetism and Aeronomy with Special Historical Case Studies. IAGA Newsletters 29/1997: 107. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1997gash.conf..107P&db_key=PHY&data_type=HTML&format=&high=42ca922c9c26415.
- ^ Professor Alf Egeland. "Olav Christian Bernhard Birkeland". Research group for Plasma and Space Physics, University of Oslo. http://www.fys.uio.no/plasma/historie/birkeland/.
- ^ Murdin, P. (2001). "Birkeland, Kristian (1868-1917)". in Murdin, P.. Encyclopedia of Astronomy and Astrophysics. pp. 5443. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001eaa..bookE5443.&db_key=AST&data_type=HTML&format=&high=42ca922c9c21201.
- ^ "Polar Magnetic Phenomena and Terrella Experiments". The Norwegian Aurora Polaris Expedition 1902-1903. 1913. pp. 720.
- ^ "Are the Solar Corpuscular Rays that penetrate the Earth's Atmosphere Negative or Positive Rays?". Videnskapsselskapets Skrifter, I Mat -- Naturv. Klasse No.1. Christiania, 1916..
- ^ Sato, T.; Iijima, T. (1979). "Primary sources of large-scale Birkeland currents". Space Science Reviews 24: 347-366. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1979SSRv...24..347S&db_key=AST&data_type=HTML&format=&high=42ca922c9c21201.
- ^ Potemra, T. A. (1978). "Observation of Birkeland currents with the TRIAD satellite". Astrophysics and Space Science 58 (1): 207-226. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1978Ap%26SS..58..207P&db_key=AST&data_type=HTML&format=&high=42ca922c9c21201.
- ^ Potemra, T. A. (1985). "Field-aligned (Birkeland) currents". Space Science Reviews 42: 295-311. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1985SSRv...42..295P&db_key=AST&data_type=HTML&format=&high=42ca922c9c21201.
- ^ Potemra, T. A. (1988). "Birkeland currents in the earth's magnetosphere". Astrophysics and Space Science 144 (1-2): 155-169. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1988Ap%26SS.144..155P&db_key=AST&data_type=HTML&format=&high=42ca922c9c21201.
- ^ quoted in L. Jago, The Northern Lights (2002), p279. The implication is that the quote is from his great work, The Norwegian Aurora Polaris Expedition 1902-1903 - see book references below
- ^ quoted in L.Jago The Northern Lights (2002), p285 - apparently said in Notoddden, 1910 - see book reference below
External links
Books
Articles
