AURORA - AURORA [POLARIS] The Luminousb @X 1. Aurora Among...

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AURORA [POLARIS] The Luminous Aurora 1. Among the oldest known geophysical phenomena 2. The most obvious characteristic of the high latitude ionosphere 3. The most readily observable consequence of the dynamic magnetosphere Historical outline of Auroral Imaging ( 20,000 B.C. earliest depictions(?): Serpertine meanders (macaronis) in cave drawings by Cro-Magnon 1575 First published scientific illustration by Cornelius Gemma 1885 Sophus Tromholt attempts photography ; gets a blurry blob after 8 minute exposure 1892 Martin Brendel obtains first useful (B&W) photographs 1910-43 Carl Störmer takes thousands of photos 1913 Störmer records movie (4 seconds per frame) 1940 Störmer begins unsuccessful attempts at color photography 1951 Gartlein and Petrie present color photos at Auroral Conference in London, Canada June 1953 Life Magazine publishes color photos 1968 Imaging with orbiting satellites begins 1970's Color movies become practical with availability of high-speed color film 1980's Significant improvements due to low light television technology International Brightness Coefficient (. ) Coefficient Appearance Equivalent to: Brightness IBC0 subvisual < 1 kRa IBC1 appears white Milky Way 1 kRa IBC2 onset of color perception Thin moonlit cirrus 10 kRa IBC3 bright stars don't shine through Moonlit cumulus 100 kRa IBC4 casts shadows Full moonlight 1000 kRa HISTORICAL RECORD Ancient various terms including flaming heavens, cracks in the heavens, burning clouds, fire dragons, and heavenly armies or battles. Sometimes it is difficult to discerned whether other phenomena (meteors, comets, St. Elmo's fire) are actually being described. ca. 2600 BC Possibly first written description in Bamboo Album of Chronology (Chu-Shu- Chi-Nien)
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8th c. BC Hesiod in Theogony describes flaming heavens, fiery sky dragons 687 BC First aurora listed in Chinese historical catalogs (through to the 10th c. AD) ca. 460 BC Mention in histories of Livy and Dionysius (Roman) ca. 340 BC Infiltration during night of the army of Philip of Macedonia into the city of Byzantium reputably foiled by light from aurora 37 AD Tiberius mistakenly sends Roman army to put out fire seen on the horizon 555 Earliest mention in England by Mathew of Westminster 919 Earliest event known in written Russian record 1100's regular observers (Mathieu of Edesse - Middle East; Vysehrad - Prague; Gervasius - England) 1111 Victory of outnumbered Russian army over Polovtsy attributed to appearance of aurora behind Russian - _ - 1192 Great Aurora of 1192 1200-1500 few recorded auroral sightings due to warfare (e.g. Mongol threat, Crusades), plague (Black Death), religious dogma (generally a bad time had by all) 1400-1500 Spörer Minimum (little solar activity) 1500's Renewed auroral activity reported in Europe 1643 First sighting with known written report in North America (by John Winthrop, Governor of Massachusetts) 1645-1715 Maunder Minimum (little solar activity) 3/17/1716 Great Aurora over Europe 1719 Bright aurora over New England and China
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AURORA - AURORA [POLARIS] The Luminousb @X 1. Aurora Among...

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