Ingrid Sandahl Swedish Institute of Space Physics, Kiruna
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Transcript of Ingrid Sandahl Swedish Institute of Space Physics, Kiruna
EoI#118EoI#118 Auroral Optical NetworkAuroral Optical NetworkInternational Network for Auroral Optical International Network for Auroral Optical Studies of the Polar IonosphereStudies of the Polar Ionosphere
Ingrid SandahlSwedish Institute of Space Physics, Kiruna
Photo: Christer Fuglesang ESA/NASA
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Optical measurements are really important for understanding the aurora and the magnetosphere
Temporal and spatial variations
Photo: Y. Ebihara
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Spectral linesLine intensityLine intensity ratiosDoppler shift
• Primary particle distribution
• Energy input• Microphysics of
the ionosphere
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Auroral Optical Network International Network for Auroral Optical Studies of the Polar Ionosphere
• IPY Expression of Intent, Jan 2005• Network for research groups carrying out optical
measurements of the aurora.
• Forum for planning coordinated measurement campaigns and for distributing information.
• Intercalibration between different sets of instruments located in different parts of the world.
• Meeting point: Optical meetings, dedicated workshops
• Home page: www.irf.se/auropt
• Mailing list: [email protected]
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Participating countries • Canada• China• Finland• Great Britain• Japan• Norway• Russia• USA
Photo: Rolf Gustafsson
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http://www.irf.se/auropt
• Present contents – mainly links– Institutions– Instruments and observing stations– Calibrations facilities (coming)– Calendar of campaigns and meetings– Mailing list information– Popular science pages
• Web links• List of literature
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Calibration of Optical Instruments
• Time for truly quantitative measurements
• Need for intercalibration between different instruments
• Need to develop calibration methods
• Calibration of imagers complicated
Toepfer spectrograph and Geissler vacuum tube used at Treurenberg Bay, Spitsbergen 1899-1900. (Westman, 1904)
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"Daughter project":Optical Auroral Research in the Arctic Region
• Projekt financed by the Nordic Council of Ministers. (IPY-related projects)
• Participants: Apatity, Oulu, Sodankylä, Kiruna, Tromsö, Longyearbyen
• Workshop Sodankylä 19-23 februari• Mobility sprogram• Plans for the future: Common Ph. D.
courses
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Imaging from space Overview, UV, dayside aurora
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Groundbased instrumentsDetailed information
• Spectrographs• Photometers
– Meridian scanning photometers, MSP
• Imaging instruments– Panchromatic/Monochromatic – FOW: Narrow to All-sky– Detector: TV, CCD, ICCD, EMCCD,
(film)
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Status of groundbased optical measurements of aurora
Important results from All-sky cameras during IGY 1957/58 - Auroral oval - Substorm
• Renewed interest• Technology revolution
– Digital– CCDs, EMCCDs– Lack of standardization
• Good instruments expensive
• Gaps in coverage• Qantitative
measurements
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Auroral imager arrays MIRACLE
THEMIS all-sky imager array
ALIS
Automatic Geophysical Observatory (AGO) stations
Svalbard
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ALIS (Auroral Large Imaging System)
• Six CCD detectors • FOV 60 or 90 degrees• Maximum resolution:
100 m at 100 km• Filter wheel, 6 pos.,
interference filters• High sensitivity,few
Rayleighs• Remote control• Campaign mode
Tomography
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ALIS data
• Freely available on Internet at alis.irf.se• Fits format• Some delay because the data must be
picked up from the stations• Welcome to use ALIS!
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Misato Observatory All-sky camera, Abisko tourist stationhttp://www.abisko.nu/sommar06/aurorawebcam/index.html
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Auroral photos obtained in 1899 by Josef Sykora at Konstantinovka, Spitsbergen
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Proposed role in ICESTAR/IHYContact for optical research groups on the following topics:
• Antarctic Space Weather service
• Interhemispheric comparisons
• Dayside geospace phenomena
• Physics of 630 nm emission
• Plasmasphere dynamics• Universality of auroras
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Challenges--things to discuss
• In what ways can the Auroral Optical Network help the scientific coummunity?
• How do we avoid duplicating work?• Interface to GAIA?• Should we register a neutral address?• What should we do about calibration?
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Conclusions• Optical measurements are
necessary to understand the aurora
• We should take advantage of the possibilities of modern instrumentation
• The purpose of the Auroral Optical Network is to promote collaboration in the field of optical auroral research during IPY and beyond.