Physics of auroral phenomena : proceedings of the 35th Annual seminar, Apatity, 28 Februaru – 02 March, 2012 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2012. - 187 с. : ил., табл.

"Physics o fAuroral Phenomena", Proc. XXXV Annual Seminar, Apatity, pp. 41 - 44, 2012 © Kola Science Centre, Russian Academy of Science, 2012 ON TRIANGULATION BY AURORAL CAMERAS Polar Geophysical Institute B.V. Kozelov, S.V. Pilgaev, L.P. Borovkov, V.E. Yurov (Polar Geophysical Institute, Apatity, Murmansk region, 184209 Russia) Abstract. The data of the MAIN (Multiscale Aurora Imaging Network) auroral cameras located in Apatity and all-sky camera in Lovozero observatory have been used to triangulate auroral structures. Two pairs of cameras are possible to employ: i) narrow (18°) field-of- view cameras with ~4 km distance between them and ii) two all-sky cameras which are ~86 km spaced. Triangulation abilities and discrepancies are tested by events of satellite flashes and meteor tracks. The results are compared with previous findings and theoretical estimations. the altitude profiles of auroral luminosity [Omholt, 1971]. Later more complicated tomographic methods and direct measurements of the particle spectra by satellites were widely used. However the simple triangulation still can be useful tool for auroral studies with specific equipment. Here we present an example of such equipment aimed to triangulation of small-scale aurora structure. The triangulation method abilities and discrepancies are tested by events of satellite flashes and meteor tracks. An example of triangulation of pulsing aurora event is discussed. The results are compared with previous findings and theoretical estimations. 1. Guppy F-044C, ~ b f ||j | 2. Guppy F-044B, (glass filter ~558 пм), т Щ э motorized pan-tilt г п Л В +GPS synchronization Wi-Fi connection Introduction There is a long history of triangulation measurements of the aurora altitude. Already C. Stormer [1910, 1911] used first photographic registrations of aurora to deduce the height profile of the glow. Later, in 60-70-th years of XX century, this method was used systematically [Иванов, 1975; Иванов и Старков, 1977; Brown et al., 1976; Stenbaek-Nielsen et al., 1978]. That time, the knowledge of the particle collisional physics in the Earth’s atmosphere was enough to obtain important information about energies of the auroral particles from Equipment Last years a new system of auroral cameras has been installed at Kola Peninsula. A schema of the observational system is shown in Fig. 1. Four cameras were operated automatically during dark time, independently of weather conditions. The cameras were installed on the main building of the Apatity division of the Polar Geophysical Institute (PGI) and at Apatity stratospheric range. The system is described in details in paper [Kozelov et al., 2012]. 1. ali-sky camera 2. Guppy F-044B, ~18° (glass filter ~558 пм), motorized pan-tilt mount +GPS synchronization + weather station +auroral spectrograph 4120 m PGI building Apatity range Fig. 1. Schema of the auroral camera network. Two identical cameras AVT Guppy F-044B NIR with narrow (18°) field of view are aimed to be used for triangulation. More information on the cameras is available at vendor’s web-site http://www. alliedvisiontec.com . Here we only mention that the cameras contain the most sensitive non-intensified Sony CCD sensors of TV format. Each camera is placed in an individual housing box with a heater located near the input glass window. Both cameras are additionally equipped by blue-green glass filter to decrease influence of long-lived excited states. The cameras were mounted on industrial pan-tilt motorized mounts to fit the 41