How Light Pollution Affects the Stars: Magnitude Readers
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GLOBE at Night: Using Sky Quality Meters to Measure Sky Brightness
GLOBE at Night: using Sky Quality Meters to measure sky brightness This document includes: • How to observe with the SQM o The SQM, finding latitude and longitude, when to observe, taking and reporting measurements, what do the numbers mean, comparing results • Demonstrating light pollution o Background in light pollution and lighting, materials needed for the shielding demo, doing the shielding demo • Capstone activities (and resources) • Appendix: An excel file for multiple measurements CREDITS This document on citizen-scientists using Sky Quality Meters to monitor light pollution levels in their community was a collaborative effort between Connie Walker at the National Optical Astronomy Observatory, Chuck Bueter of nightwise.org, Anna Hurst of ASP’s Astronomy from the Ground Up program, Vivian White and Marni Berendsen of ASP’s Night Sky Network and Kim Patten of the International Dark-Sky Association. Observations using the Sky Quality Meter (SQM) The Sky Quality Meters (SQMs) add a new twist to the GLOBE at Night program. They expand the citizen science experience by making it more scientific and more precise. The SQMs allow citizen-scientists to map a city at different locations to identify dark sky oases and even measure changes over time beyond the GLOBE at Night campaign. This document outlines how to make and report SQM observations. Important parts of the SQM ! Push start button here. ! Light enters here. ! Read out numbers here. The SQM Model The SQM-L Model Using the SQM There are two models of Sky Quality Meters. Information on the newer model, the SQM- L, can be found along with the instruction sheet at http://unihedron.com/projects/sqm-l/. -
The Dawn Sky Brightness Observations in the Preliminary Shubuh Prayer Time Determination
QIJIS: Qudus International Journal of Islamic Studies Volume 6, Issue 1, February 2018 THE DAWN SKY BRIGHTNESS OBSERVATIONS IN THE PRELIMINARY SHUBUH PRAYER TIME DETERMINATION Laksmiyanti Annake Harijadi Noor Bandung Institute of Technology (ITB) Bandung, West Java [email protected] Fahmi Fatwa Rosyadi Satria Hamdani Bandung Islamic University (UNISBA) Bandung, West Java [email protected] Abstract The indication of began to enter the shubuh prayer time is when emerge the morning dawn and lasted until the sun rises. The sun position when emerge the morning dawn is below the intrinsic horizon marked with a minus sign (-) with the value of a certain height. The Ministry of Religious Affairs has set the sun altitudes of dawn in the shubuh prayer time with minus (-) 19° + sunrise/sunset altitudes as standard is the reference time of dawn prayers in Indonesia. However, this provision in fact reap discourse in some quarters because it is not in accordance with the phenomenon of morning dawn emergence at the beginning of the shubuh prayer time empirically. This study aims to decide the morning dawn, as the beginning of dawn determinant. The tool used in this study is the Sky Quality Meter (SQM), to detecting the morning dawn emergence as a sign of the beginning of the shubuh prayer time. The results of this study found that the brightness of the sky throughout Fahmi Fatwa Rosyadi Satria Hamdani the night or the morning dawn in Tayu Beach, Pati, Central Java, in the span of four days of observation that is at 04.31 A.M. with an average altitude of the sun is -17°(17° below the horizon). -
Daytime Sky Brightness Characterization for Persistent GEO SSA
Daytime sky brightness characterization for persistent GEO SSA Grant M. Thomas Air Force Institute of Technology, Wright-Patterson AFB, Ohio Richard G. Cobb Air Force Institute of Technology, Wright-Patterson AFB, Ohio ABSTRACT Space Situational Awareness (SSA) is fundamental to operating in space. SSA for collision avoidance ensures safety of flight for both government and commercial spacecraft through persistent monitoring. A worldwide network of optical and radar sensors gather satellite ephemeris data from the nighttime sky. Current practice for daytime satellite tracking is limited exclusively to radar as the brightening daytime sky prevents the use of visible-band optical sensors. Radar coverage is not pervasive and results in significant daytime coverage gaps in SSA. To mitigate these gaps, optical telescopes equipped with sensors in the near-infrared band (0.75-0.9µm) may be used. The diminished intensity of the background sky radiance in the near-infrared band may allow for daylight tracking further into the twilight hours. To determine the performance of a near-infrared sensor for daylight custody, the sky background radiance must first be characterized spectrally as a function of wavelength. Using a physics-based atmospheric model with access to near-real time weather, we developed a generalized model for the apparent sky brightness of the Geostationary satellite belt. The model results are then compared to measured data collected from Dayton, OH through various look and Sun angles for model validation and spectral sky radiance quantification in the visible and near-infrared bands. 1 INTRODUCTION Spectral sky radiance or spectral sky brightness is a measure of the radiant intensity at each wavelength of the atmosphere. -
Measuring Night Sky Brightness: Methods and Challenges
Measuring night sky brightness: methods and challenges Andreas H¨anel1, Thomas Posch2, Salvador J. Ribas3,4, Martin Aub´e5, Dan Duriscoe6, Andreas Jechow7,13, Zolt´anKollath8, Dorien E. Lolkema9, Chadwick Moore6, Norbert Schmidt10, Henk Spoelstra11, G¨unther Wuchterl12, and Christopher C. M. Kyba13,7 1Planetarium Osnabr¨uck,Klaus-Strick-Weg 10, D-49082 Osnabr¨uck,Germany 2Universit¨atWien, Institut f¨urAstrophysik, T¨urkenschanzstraße 17, 1180 Wien, Austria tel: +43 1 4277 53800, e-mail: [email protected] (corresponding author) 3Parc Astron`omicMontsec, Comarcal de la Noguera, Pg. Angel Guimer`a28-30, 25600 Balaguer, Lleida, Spain 4Institut de Ci`encies del Cosmos (ICCUB), Universitat de Barcelona, C.Mart´ıi Franqu´es 1, 08028 Barcelona, Spain 5D´epartement de physique, C´egep de Sherbrooke, Sherbrooke, Qu´ebec, J1E 4K1, Canada 6Formerly with US National Park Service, Natural Sounds & Night Skies Division, 1201 Oakridge Dr, Suite 100, Fort Collins, CO 80525, USA 7Leibniz-Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany 8E¨otv¨osLor´andUniversity, Savaria Department of Physics, K´arolyi G´asp´ar t´er4, 9700 Szombathely, Hungary 9National Institute for Public Health and the Environment, 3720 Bilthoven, The Netherlands 10DDQ Apps, Webservices, Project Management, Maastricht, The Netherlands 11LightPollutionMonitoring.Net, Urb. Ve¨ınatVerneda 101 (Bustia 49), 17244 Cass`ade la Selva, Girona, Spain 12Kuffner-Sternwarte,Johann-Staud-Straße 10, A-1160 Wien, Austria 13Deutsches GeoForschungsZentrum Potsdam, Telegrafenberg, 14473 Potsdam, Germany Abstract Measuring the brightness of the night sky has become an increasingly impor- tant topic in recent years, as artificial lights and their scattering by the Earth’s atmosphere continue spreading around the globe. -
Snowglow—The Amplification of Skyglow by Snow and Clouds Can
Journal of Imaging Article Snowglow—The Amplification of Skyglow by Snow and Clouds Can Exceed Full Moon Illuminance in Suburban Areas Andreas Jechow 1,2,* and Franz Hölker 1,3 1 Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, 12587 Berlin, Germany 2 Remote Sensing, GFZ German Research Centre for Geosciences, 14473 Potsdam, Germany 3 Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany * Correspondence: [email protected] Received: 27 June 2019; Accepted: 29 July 2019; Published: 1 August 2019 Abstract: Artificial skyglow, the fraction of artificial light at night that is emitted upwards from Earth and subsequently scattered back within the atmosphere, depends on atmospheric conditions but also on the ground albedo. One effect that has not gained much attention so far is the amplification of skyglow by snow, particularly in combination with clouds. Snow, however, has a very high albedo and can become important when the direct upward emission is reduced when using shielded luminaires. In this work, first results of skyglow amplification by fresh snow and clouds measured with all-sky photometry in a suburban area are presented. Amplification factors for the zenith luminance of 188 for snow and clouds in combination and 33 for snow alone were found at this site. The maximum zenith luminance of nearly 250 mcd/m2 measured with snow and clouds is a factor of 1000 higher than the commonly used clear sky reference of 0.25 mcd/m2. Compared with our darkest zenith luminance of 0.07 mcd/m2 measured for overcast conditions in a very remote area, this leads to an overall amplification factor of ca. -
Light Pollution, Sleep Deprivation, and Infant Health at Birth
DISCUSSION PAPER SERIES IZA DP No. 11703 Light Pollution, Sleep Deprivation, and Infant Health at Birth Laura M. Argys Susan L. Averett Muzhe Yang JULY 2018 DISCUSSION PAPER SERIES IZA DP No. 11703 Light Pollution, Sleep Deprivation, and Infant Health at Birth Laura M. Argys University of Colorado Denver and IZA Susan L. Averett Lafayette College and IZA Muzhe Yang Lehigh University JULY 2018 Any opinions expressed in this paper are those of the author(s) and not those of IZA. Research published in this series may include views on policy, but IZA takes no institutional policy positions. The IZA research network is committed to the IZA Guiding Principles of Research Integrity. The IZA Institute of Labor Economics is an independent economic research institute that conducts research in labor economics and offers evidence-based policy advice on labor market issues. Supported by the Deutsche Post Foundation, IZA runs the world’s largest network of economists, whose research aims to provide answers to the global labor market challenges of our time. Our key objective is to build bridges between academic research, policymakers and society. IZA Discussion Papers often represent preliminary work and are circulated to encourage discussion. Citation of such a paper should account for its provisional character. A revised version may be available directly from the author. IZA – Institute of Labor Economics Schaumburg-Lippe-Straße 5–9 Phone: +49-228-3894-0 53113 Bonn, Germany Email: [email protected] www.iza.org IZA DP No. 11703 JULY 2018 ABSTRACT Light Pollution, Sleep Deprivation, and Infant Health at Birth* This is the first study that uses a direct measure of skyglow, an important aspect of light pollution, to examine its impact on infant health at birth. -
Measurements of Night Sky Brightness in the Veneto Region of Italy: Sky Quality Meter Network Results and Differential Photometry by Digital Single Lens Reflex
Journal of Imaging Article Measurements of Night Sky Brightness in the Veneto Region of Italy: Sky Quality Meter Network Results and Differential Photometry by Digital Single Lens Reflex Andrea Bertolo 1,* , Renata Binotto 1, Sergio Ortolani 2,3 and Simone Sapienza 1 1 Regional Environmental Protection Agency of Veneto, Via Ospedale Civile 24, 35121 Padova, Italy; [email protected] (R.B.); [email protected] (S.S.) 2 Department of Physics and Astronomy, University of Padova, vicolo dell’Osservatorio 2, 35122 Padova, Italy; [email protected] 3 INAF, Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy * Correspondence: [email protected] Received: 3 April 2019; Accepted: 21 May 2019; Published: 24 May 2019 Abstract: In this paper, we present the implementation of a monitoring network for artificial light at night (ALAN), based on Sky Quality Meter devices (SQM) installed in seven locations of the Veneto region. The system is coordinated by the Regional Environmental Protection Agency (ARPA-Veneto) and the Department of Physics and Astronomy of the University of Padova, in collaboration with a local dark-sky association, Venetostellato. A new centralized database containing zenith night sky brightness (NSB) data was implemented to collect data from all SQM stations of the regional territory, not only in real time (since 2017), but in some stations since 2011. We now have a dataset to determine how light pollution is affecting astronomical observatories. A WEB portal was created to offer different downloads from these NSB data. We present the results of some elaborations for the 2018 dataset (statistics, histograms, annual and cumulative plots) for seven monitoring sites. -
A Model to Determine Naked-Eye Limiting Magnitude
Volume 10 Issue 1 (2021) HS Research A Model to Determine Naked-Eye Limiting Magnitude Dasha Crocker1, Vincent Schmidt1 and Laura Schmidt1 1Bellbrook High School, Bellbrook, OH, USA ABSTRACT The purpose of this study was to determine which variables would be needed to generate a model that predicted the naked eye limiting magnitude on a given night. After background research was conducted, it seemed most likely that wind speed, air quality, skyglow, and cloud cover would contribute to the proposed model. This hypothesis was tested by obtaining local weather data, then determining the naked eye limiting magnitude for the local conditions. This procedure was repeated for the moon cycle of October, then repeated an additional 11 times in November, December, and January. After the initial 30 trials, r values were calculated for each variable that was measured. These values revealed that wind was not at all correlated with the naked eye limiting magnitude, but pollen (a measure of air quality), skyglow, and cloud cover were. After the generation of several models using multiple regression tests, air quality also proved not to affect the naked eye limiting magnitude. It was concluded that skyglow and cloud cover would contribute to a model that predicts naked eye limiting magnitude, proving the original hypothesis to be partially correct. Introduction Humanity has been looking to the stars for thousands of years. Ancient civilizations looked to the stars hoping that they could explain the world around them. Mayans invented shadow casting devices to track the movement of the sun, moon, and planets, while Chinese astronomers discovered Ganymede, one of Jupiter’s moons (Cook, 2018). -
The 1997 Reference of Diffuse Night Sky Brightness
ASTRONOMY & ASTROPHYSICS JANUARY I 1998,PAGE1 SUPPLEMENT SERIES Astron. Astrophys. Suppl. Ser. 127, 1-99 (1998) The 1997 reference of diffuse night sky brightness? Ch. Leinert1,S.Bowyer2, L.K. Haikala3, M.S. Hanner4,M.G.Hauser5, A.-Ch. Levasseur-Regourd6, I. Mann7,K.Mattila3, W.T. Reach8, W. Schlosser9, H.J. Staude1, G.N. Toller10, J.L. Weiland11, J.L. Weinberg12, and A.N. Witt13 1 Max–Planck–Institut f¨ur Astronomie, K¨onigstuhl 17, D-69117 Heidelberg, Germany 2 Astronomy Dept., University of California, 601 Campbell Hall, Berkeley CA 94720, U.S.A. 3 Observatory, P.O. Box 14, FIN-00014 University of Helsinki, Finland 4 Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena CA 91109, U.S.A. 5 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore MD 21218, U.S.A. 6 Service d’A´eronomie, BP. 3, F-91371 Verri`eres le Buisson, France 7 Max–Planck–Institut f¨ur Aeronomie, Max-Planck-Straße 2, D-37191 Katlenburg-Lindau, Germany 8 Institut d’Astrophysique Spatiale, Universit´e Paris XI, 91405 Orsay Cedex, France 9 Astronomisches Institut, Ruhr-Universit¨at Bochum, D-44780 Bochum, Germany 10 General Sciences Corporation, 6100 Chevy Chase Drive, Laurel, MD 20707, U.S.A. 11 Hughes STX, NASA/Goddard Space Flight Center Code 685.9, Greenbelt, MD 20771, U.S.A. 12 MK Industries, 2137E Flintstone Drive, Tucker, Georgia 30084, U.S.A. 13 Ritter Astrophys. Res. Center, University of Toledo, Toledo, OH 43606, U.S.A. Received August 7; accepted September 8, 1997 Abstract. In the following we present material in tabu- 6.4 Geocorona lar and graphical form, with the aim to allow the non- 6.5 Interplanetary emissions specialist to obtain a realistic estimate of the diffuse night 6.6 Shuttle glow sky brightness over a wide range of wavelengths from the 7. -
A Simplified Model of All-Sky Artificial Sky Glow Derived from VIIRS Day
Journal of Quantitative Spectroscopy & Radiative Transfer 214 (2018) 133–145 Contents lists available at ScienceDirect Journal of Quantitative Spectroscopy & Radiative Transfer journal homepage: www.elsevier.com/locate/jqsrt A simplified model of all-sky artificial sky glow derived from VIIRS Day/Night band data ∗ Dan M. Duriscoe a, Sharolyn J. Anderson b, , Christian B. Luginbuhl c, Kimberly E. Baugh d a U.S. National Park Service Night Skies Program (retired), Big Pine, CA, USA b National Park Service, Natural Sounds and Night Skies, Fort Collins, CO, USA c Dark Sky Partners LLC, Tucson, AZ, USA d University of Colorado- CIRES, Boulder, CO, USA a r t i c l e i n f o a b s t r a c t Article history: We present a simplified method using geographic analysis tools to predict the average artificial luminance Received 15 November 2017 over the hemisphere of the night sky, expressed as a ratio to the natural condition. The VIIRS Day/Night Revised 25 April 2018 Band upward radiance data from the Suomi NPP orbiting satellite was used for input to the model. The Accepted 25 April 2018 method is based upon a relation between sky glow brightness and the distance from the observer to the Available online 26 April 2018 source of upward radiance. This relationship was developed using a Garstang radiative transfer model Keywords: with Day/Night Band data as input, then refined and calibrated with ground-based all-sky V-band photo- Night sky brightness metric data taken under cloudless and low atmospheric aerosol conditions. An excellent correlation was Light pollution found between observed sky quality and the predicted values from the remotely sensed data. -
Lab 2: Sky Brightness
Lab 2: Sky Brightness As we discussed in class, the brightness of the night sky during an observation depends upon a number of factors. These factors include the wavelength of the observations, airmass, cloud-cover, the location and phase of the moon, and terrestrial light pollution. In this lab your objective is to directly investigate the sky brightness at Rosemary Hill Observatory using a sky quality meter during our RHO trip. As always, the lab report that you turn in should provide clear explanations of your work, and include the requested numbers, figures, and tables. Objectives: Your basic objectives for the lab are the following. 1. Quantify the dependence of sky brightness upon time after sunset. 2. Quantify the dependence of sky brightness upon zenith angle. 3. Compare the minimum sky brightness at Rosemary Hill Observatory with numbers for at least one other research observatory at a dark site (be sure to cite your reference for these numbers). Your report should include a table with the darkest sky levels at each site. 4. Discuss and attempt to explain any anomalous data. Procedure: During the trip to RHO, we will have on hand a sky quality meter. The unit is point-and- shoot, providing the sky brightness in visual magnitudes per square arcsec. The Full Width Half Maximum (FWHM) of the angular sensitivity is 20 degrees, so if you for example point at zenith the meter is sensitive to the sky brightness within ~10 degrees. We will share the meter as a class. All measurements should be made from a single location. -