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- Birkeland_current abstract "A Birkeland current is a set of currents that flow along geomagnetic field lines connecting the Earth’s magnetosphere to the Earth's high latitude ionosphere. In the Earth’s magnetosphere, the currents are driven by the solar wind and interplanetary magnetic field and by bulk motions of plasma through the magnetosphere (convection indirectly driven by the interplanetary environment). The strength of the Birkeland currents changes with activity in the magnetosphere (e.g. during substorms). Small scale variations in the upward current sheets (downward flowing electrons) accelerate magnetospheric electrons which, when they reach the upper atmosphere, create the Auroras Borealis and Australis. In the high latitude ionosphere (or auroral zones), the Birkeland currents close through the region of the auroral electrojet, which flows perpendicular to the local magnetic field in the ionosphere. The Birkeland currents occur in two pairs of field-aligned current sheets. One pair extends from noon through the dusk sector to the midnight sector. The other pair extends from noon through the dawn sector to the midnight sector. The sheet on the high latitude side of the auroral zone is referred to as the Region 1 current sheet and the sheet on the low latitude side is referred to as the Region 2 current sheet.The currents were predicted in 1908 by Norwegian explorer and physicist Kristian Birkeland, who undertook expeditions beyond the Arctic Circle to study the aurora. He rediscovered, using simple magnetic field measurement instruments, that when the aurora appeared the needles of magnetometers changed direction, confirming the findings of Anders Celsius and assistant Olof Hjorter more than a century before. This could only imply that currents were flowing in the atmosphere above. He theorized that somehow the Sun emitted a cathode ray, and corpuscles from what is now known as a solar wind entered the Earth’s magnetic field and created currents, thereby creating the aurora. This view was scorned by other researchers, but in 1967 a satellite, launched into the auroral region, showed that the currents posited by Birkeland existed. In honour of him and his theory these currents are named Birkeland currents. A good description of the discoveries by Birkeland is given in the book by Jago.Professor Emeritus of the Alfvén Laboratory in Sweden, Carl-Gunne Fälthammar wrote: \"A reason why Birkeland currents are particularly interesting is that, in the plasma forced to carry them, they cause a number of plasma physical processes to occur (waves, instabilities, fine structure formation). These in turn lead to consequences such as acceleration of charged particles, both positive and negative, and element separation (such as preferential ejection of oxygen ions). Both of these classes of phenomena should have a general astrophysical interest far beyond that of understanding the space environment of our own Earth.\"".
- Birkeland_current thumbnail Schematic-of-combined-FACs-and-ionospheric-current-systems.png?width=300.
- Birkeland_current wikiPageExternalLink nph-abs_connect?db_key=ALL&bibstem=Astrophysics+and+Space+Science&year=1988&volume=144.
- Birkeland_current wikiPageExternalLink nph-bib_query?bibcode=1988Ap%26SS.144..155P&db_key=AST&data_type=HTML&format=&high=42ca922c9c21187.
- Birkeland_current wikiPageExternalLink nph-data_query?bibcode=1963IAUS...16...35A&db_key=AST&link_type=ABSTRACT&high=42ca922c9c23043.
- Birkeland_current wikiPageExternalLink nph-data_query?bibcode=1967SSRv....7..140A&db_key=AST&link_type=ABSTRACT&high=42ca922c9c23043.
- Birkeland_current wikiPageExternalLink nph-data_query?bibcode=1967SoPh....1..220A&db_key=AST&link_type=ABSTRACT&high=42ca922c9c23043.
- Birkeland_current wikiPageExternalLink nph-data_query?bibcode=1975SSRv...17..563C&db_key=AST&link_type=ABSTRACT&high=42ca922c9c00817.
- Birkeland_current wikiPageExternalLink nph-data_query?bibcode=1978Ap%26SS..58..207P&db_key=AST&link_type=ABSTRACT&high=42ca922c9c00817.
- Birkeland_current wikiPageExternalLink ampere.jhuapl.edu.
- Birkeland_current wikiPageExternalLink nph-iarticle_query?1988Ap%26SS.144...73C.
- Birkeland_current wikiPageExternalLink dysprosium.jhuapl.edu.
- Birkeland_current wikiPageExternalLink elec_currents.html.
- Birkeland_current wikiPageExternalLink pinch_en.html.
- Birkeland_current wikiPageExternalLink Physics_of_the_Plasma_Universe_%28Book%29.
- Birkeland_current wikiPageExternalLink 0,11855,5-10100-72-39144987-0,00.html.
- Birkeland_current wikiPageID "2621261".
- Birkeland_current wikiPageLength "18113".
- Birkeland_current wikiPageOutDegree "49".
- Birkeland_current wikiPageRevisionID "694403791".
- Birkeland_current wikiPageWikiLink Ampere.
- Birkeland_current wikiPageWikiLink Ampxc3xa8res_force_law.
- Birkeland_current wikiPageWikiLink Anders_Celsius.
- Birkeland_current wikiPageWikiLink Arctic_Circle.
- Birkeland_current wikiPageWikiLink Aurora.
- Birkeland_current wikiPageWikiLink Carl-Gunne_Fälthammar.
- Birkeland_current wikiPageWikiLink Category:Ionosphere.
- Birkeland_current wikiPageWikiLink Diocotron_instability.
- Birkeland_current wikiPageWikiLink Double_layer_(plasma).
- Birkeland_current wikiPageWikiLink Earths_magnetic_field.
- Birkeland_current wikiPageWikiLink Electrojet.
- Birkeland_current wikiPageWikiLink Electromagnetism.
- Birkeland_current wikiPageWikiLink File:Schematic-of-combined-FACs-and-ionospheric-current-systems.png.
- Birkeland_current wikiPageWikiLink Gamma_ray.
- Birkeland_current wikiPageWikiLink Hannes_Alfvén.
- Birkeland_current wikiPageWikiLink Instability.
- Birkeland_current wikiPageWikiLink Interplanetary_magnetic_field.
- Birkeland_current wikiPageWikiLink Ionosphere.
- Birkeland_current wikiPageWikiLink Joule_heating.
- Birkeland_current wikiPageWikiLink Kelvin–Helmholtz_instability.
- Birkeland_current wikiPageWikiLink Kristian_Birkeland.
- Birkeland_current wikiPageWikiLink List_of_plasma_(physics)_articles.
- Birkeland_current wikiPageWikiLink Magnetohydrodynamics.
- Birkeland_current wikiPageWikiLink Magnetometer.
- Birkeland_current wikiPageWikiLink Magnetosphere.
- Birkeland_current wikiPageWikiLink Olof_Hiorter.
- Birkeland_current wikiPageWikiLink Optics.
- Birkeland_current wikiPageWikiLink Pinch_(plasma_physics).
- Birkeland_current wikiPageWikiLink Plasma_acceleration.
- Birkeland_current wikiPageWikiLink Plasma_cosmology.
- Birkeland_current wikiPageWikiLink Pulsed_power.
- Birkeland_current wikiPageWikiLink Radio.
- Birkeland_current wikiPageWikiLink Solar_wind.
- Birkeland_current wikiPageWikiLink Springer_Science+Business_Media.
- Birkeland_current wikiPageWikiLink Substorm.
- Birkeland_current wikiPageWikiLink Sydney_Chapman_(mathematician).
- Birkeland_current wikiPageWikiLink Synchrotron_radiation.
- Birkeland_current wikiPageWikiLink Vortex.
- Birkeland_current wikiPageWikiLink Watt.
- Birkeland_current wikiPageWikiLink Waves_in_plasmas.
- Birkeland_current wikiPageWikiLink X-ray.
- Birkeland_current wikiPageWikiLink Z-pinch.
- Birkeland_current wikiPageWikiLink File:Birkeland-anode-globe-fig259.jpg.
- Birkeland_current wikiPageWikiLink File:Birkeland-currents.gif.
- Birkeland_current wikiPageWikiLink File:Magnetic_rope.svg.
- Birkeland_current wikiPageWikiLinkText "Birkeland current".
- Birkeland_current wikiPageWikiLinkText "Birkeland_current".
- Birkeland_current wikiPageWikiLinkText "Field-aligned current".
- Birkeland_current wikiPageWikiLinkText "birkeland current".
- Birkeland_current wikiPageWikiLinkText "field aligned currents".
- Birkeland_current wikiPageWikiLinkText "field-aligned current".
- Birkeland_current wikiPageWikiLinkText "force-free magnetic fields".
- Birkeland_current wikiPageUsesTemplate Template:Doi.
- Birkeland_current wikiPageUsesTemplate Template:Magnetosphere.
- Birkeland_current wikiPageUsesTemplate Template:Reflist.
- Birkeland_current subject Category:Ionosphere.
- Birkeland_current hypernym Set.
- Birkeland_current type Physic.
- Birkeland_current type Plasma.
- Birkeland_current comment "A Birkeland current is a set of currents that flow along geomagnetic field lines connecting the Earth’s magnetosphere to the Earth's high latitude ionosphere. In the Earth’s magnetosphere, the currents are driven by the solar wind and interplanetary magnetic field and by bulk motions of plasma through the magnetosphere (convection indirectly driven by the interplanetary environment). The strength of the Birkeland currents changes with activity in the magnetosphere (e.g. during substorms).".
- Birkeland_current label "Birkeland current".
- Birkeland_current sameAs Q803957.
- Birkeland_current sameAs تيار_بيركلاند.
- Birkeland_current sameAs Corrent_de_Birkeland.
- Birkeland_current sameAs Corriente_de_Birkeland.
- Birkeland_current sameAs Courant_de_Birkeland.
- Birkeland_current sameAs Birkelandova_struja.
- Birkeland_current sameAs Birkeland-áramok.
- Birkeland_current sameAs 버켈랜드_전류.
- Birkeland_current sameAs Arus_Birkeland.
- Birkeland_current sameAs Prąd_Birkelanda.
- Birkeland_current sameAs Corrente_de_Birkeland.
- Birkeland_current sameAs m.07sbcs.
- Birkeland_current sameAs Curentul_Birkeland.
- Birkeland_current sameAs Birkelandova_struja.
- Birkeland_current sameAs Q803957.
- Birkeland_current sameAs 白克蘭電流.
- Birkeland_current wasDerivedFrom Birkeland_current?oldid=694403791.
- Birkeland_current depiction Schematic-of-combined-FACs-and-ionospheric-current-systems.png.
- Birkeland_current isPrimaryTopicOf Birkeland_current.