Fabio Del Sordo edited untitled.tex  about 9 years ago

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Svalbard is an archipelago situated at about half way between continental Norway and the North Pole, and it is an outpost for research and exploration on the arctic. In Longyearbyen, a little city with a population of about 2000 and Svalbard capital, there is UNIS, University Center in Svalbard: this is the world’s northernmost institution for higher education and research.  There’s plenty of science to be investigated during an eclipse. One of the most relevant historical examples is the \href{http://adsabs.harvard.edu/abs/1920RSPTA.220..291D}{measurement of the deflection of light by the Sun}, performed by Sir Arthur Eddington in 1919 during a total solar eclipse. Such experiment demonstrated that the sun was indeed deflecting the light, as predicted by Einstein's general theory of relativity.  But an eclipse as at  such high latitude gives an excellent opportunity to have measurement of the dayside aurora, which is a relatively common phenomena phenomenon  at Svalbard. Aurora, or northern light, is mostly known for its manifestation during the night at high latitudes, being a consequence of high-energy particles accelerated towards the terrestrial magnetic poles in the nigthside of the terrestrial magnetosphere. Nevertheless, some particles are injected by the interplanetary magnetic field also in the dayside Earth magnetospheres, so generating the dayside aurora. Still, the presence of sulight makes difficult to observe such phenomenon.  Aurora. KHO observatory Observation of dayside aurora have been carried out during the eclipse at \href{http://kho.unis.no}{KHO observatory}, a few kilometers away from Longyearbyen.  However, no northern light was visible with naked eye during the eclipse. The eclipse was, in fact, quite luminous and the sky did not get too dark. The reason is that the Sun was very low - 11 degrees - on the horizon, and the whole landscape was white. I saw the eclipse from the snow-covered valley of Adventalen, which became an almost extraterrestrial place during the two and a half minutes of darkness.