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Author Cinzano, P.
Title Night Sky Photometry with Sky Quality Meter Type Journal Article
Year 2005 Publication Technical Report 9, ISTIL. V1.4. Abbreviated Journal
Volume Issue Pages
Keywords Instrumentation; light pollution; night sky brightness; photometry; instruments; calibration
Abstract Sky Quality Meter, a low cost and pocket size night sky brightness photometer, opens to the general public the possibility to quantify the quality of the night sky. Expecting a large diffusion of measurements taken with this instrument, I tested and characterized it. I analyzed with synthetic photometry and laboratory measurements the relationship between the SQM photometrical system and the main systems used in light pollution studies. I evaluated the conversion factors to Johnson’s B and V bands, CIE photopic and CIE scotopic responses for typical spectra and the spectral mismatch correction factors when specific filters are added.
Address (up) Dipartimento di Astronomia, Vicolo dell’Osservatorio 2, I-35100 Padova, Italy; cinzano(at)lplab.it
Corporate Author Thesis
Publisher ISTIL Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ christopher.kyba @ Serial 473
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Author Cochran, W.W.; Mouritsen, H.; Wikelski, M.
Title Migrating songbirds recalibrate their magnetic compass daily from twilight cues Type Journal Article
Year 2004 Publication Science (New York, N.Y.) Abbreviated Journal Science
Volume 304 Issue 5669 Pages 405-408
Keywords *Animal Migration; Animals; Biological Clocks; Calibration; Cues; *Flight, Animal; Geography; *Magnetics; *Orientation; *Solar System; Songbirds/*physiology
Abstract Night migratory songbirds can use stars, sun, geomagnetic field, and polarized light for orientation when tested in captivity. We studied the interaction of magnetic, stellar, and twilight orientation cues in free-flying songbirds. We exposed Catharus thrushes to eastward-turned magnetic fields during the twilight period before takeoff and then followed them for up to 1100 kilometers. Instead of heading north, experimental birds flew westward. On subsequent nights, the same individuals migrated northward again. We suggest that birds orient with a magnetic compass calibrated daily from twilight cues. This could explain how birds cross the magnetic equator and deal with declination.
Address (up) Illinois Natural History Survey, 607 East Peabody Drive, Champaign, IL61820, USA. Sparrow@springnet1.com
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0036-8075 ISBN Medium
Area Expedition Conference
Notes PMID:15087541 Approved no
Call Number IDA @ john @ Serial 57
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Author Kyba, C.C.M.; Tong, K.P.; Bennie, J.; Birriel, I.; Birriel, J.J.; Cool, A.; Danielsen, A.; Davies, T.W.; Outer, P.N. den; Edwards, W.; Ehlert, R.; Falchi, F.; Fischer, J.; Giacomelli, A.; Giubbilini, F.; Haaima, M.; Hesse, C.; Heygster, G.; Hölker, F.; Inger, R.; Jensen, L.J.; Kuechly, H.U.; Kuehn, J.; Langill, P.; Lolkema, D.E.; Nagy, M.; Nievas, M.; Ochi, N.; Popow, E.; Posch, T.; Puschnig, J.; Ruhtz, T.; Schmidt, W.; Schwarz, R.; Schwope, A.; Spoelstra, H.; Tekatch, A.; Trueblood, M.; Walker, C.E.; Weber, M.; Welch, D.L.; Zamorano, J.; Gaston, K.J.
Title Worldwide variations in artificial skyglow Type Journal Article
Year 2015 Publication Scientific Reports Abbreviated Journal Sci. Rep.
Volume 5 Issue Pages 8409
Keywords Skyglow; light pollution; measurements; remote sensing; sky brightness; calibration
Abstract Despite constituting a widespread and significant environmental change, understanding of artificial nighttime skyglow is extremely limited. Until now, published monitoring studies have been local or regional in scope, and typically of short duration. In this first major international compilation of monitoring data we answer several key questions about skyglow properties. Skyglow is observed to vary over four orders of magnitude, a range hundreds of times larger than was the case before artificial light. Nearly all of the study sites were polluted by artificial light. A non-linear relationship is observed between the sky brightness on clear and overcast nights, with a change in behavior near the rural to urban landuse transition. Overcast skies ranged from a third darker to almost 18 times brighter than clear. Clear sky radiances estimated by the World Atlas of Artificial Night Sky Brightness were found to be overestimated by ~25%; our dataset will play an important role in the calibration and ground truthing of future skyglow models. Most of the brightly lit sites darkened as the night progressed, typically by ~5% per hour. The great variation in skyglow radiance observed from site-to-site and with changing meteorological conditions underlines the need for a long-term international monitoring program.
Address (up) Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Berlin, Germany
Corporate Author Thesis
Publisher Nature Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1103
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Author den Outer, P.; Lolkema, D.; Haaima, M.; van der Hoff, R.; Spoelstra, H.; Schmidt, W.
Title Intercomparisons of nine sky brightness detectors Type Journal Article
Year 2011 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)
Volume 11 Issue 10 Pages 9603-9612
Keywords Calibration; Darkness; *Extraterrestrial Environment; Humans; Light; Luminescent Measurements; Netherlands; *Optical Phenomena; Optics and Photonics/*instrumentation/*methods; Sky Quality Meter; artificial lighting; intercalibration; intercomparison; light pollution; night sky brightness
Abstract Nine Sky Quality Meters (SQMs) have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across The Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between +/-14%. Individual night time sums range from -16% to +20%. Intercalibration reduces this to 0.5%, and -7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 +/- 0.003 mcd/m(2) on 12 April, and the largest value was 5.94 +/- 0.03 mcd/m(2) on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.
Address (up) National Institute for Public Health and the Environment, A. van Leeuwenhoeklaan 9, 3720 BA Bilthoven, The Netherlands. peter.den.outer@rivm.nl
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1424-8220 ISBN Medium
Area Expedition Conference
Notes PMID:22163715; PMCID:PMC3231263 Approved no
Call Number IDA @ john @ Serial 196
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Author Cao, C.; Zong, Y.; Bai, Y.; Shao, X.
Title Preliminary study for improving the VIIRS DNB low light calibration accuracy with ground based active light source Type Journal Article
Year 2015 Publication Proc. SPIE 9607, Earth Observing Systems XX, 2015 Abbreviated Journal
Volume Issue Pages 96070D
Keywords Remote sensing; Suomi NPP; VIIRS DNB; calibration
Abstract There is a growing interest in the science and user community in the Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) low light detection capabilities at night for quantitative applications such as airglow, geophysical retrievals under lunar illumination, light power estimation, search and rescue, energy use, urban expansion and other human activities. Given the growing interest in the use of the DNB data, a pressing need arises for improving the calibration stability and absolute accuracy of the DNB at low radiances. Currently the low light calibration accuracy was estimated at a moderate 15%-100% while the long-term stability has yet to be characterized. This study investigates selected existing night light point sources from Suomi NPP DNB observations and evaluates the feasibility of SI traceable nightlight source at radiance levels near 3 nW·cm−2·sr−1, that potentially can be installed at selected sites for VIIRS DNB calibration/validation. The illumination geometry, surrounding environment, as well as atmospheric effects are also discussed. The uncertainties of the ground based light source are estimated. This study will contribute to the understanding of how the Earth’s atmosphere and surface variability contribute to the stability of the DNB measured radiances, and how to separate them from instrument calibration stability. It presents the need for SI traceable active light sources to monitor the calibration stability, radiometric and geolocation accuracy, and point spread functions of the DNB. Finally, it is also hoped to address whether or not active light sources can be used for detecting environmental changes, such as aerosols.
Address (up) NESDIS/STAR, National Oceanic and Atmospheric Administration, USA
Corporate Author Thesis
Publisher SPIE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1261
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