MEASUREMENT OF SKY BRIGHTNESS USING SKY QUALITY METER FOR DETERMINING DARK LOCATION OF ASTRONOMICAL OBSERVATION AND DETERMINATION OF TWILIGHT IN BANGKA ISLAND Mega Sukma (a*), Dhani Herdiwijaya (b), Fadilah Sabri (a), Abu Yazid Raisal (c)
a) Department of Civil Engineering, Faculty of Technique and Sciences, Muhammadiyah University Bangka Belitung, Pangkalanbaru 33684, Indonesia
*mega.sukma[at]unmuhbabel.ac.id
b) Department of Astronomy, Faculty of Mathematics and Natural Science,
Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132, Indonesia
c) Universitas Muhammadiyah Sumatera Utara
Abstract
Light pollution is a broad term that refers to a number of problems, all of which are caused by the inefficiency of using artificial light. By utilizing Sky Quality Meter (SQM), the light pollution can be measured objectively. This study examines light pollution in six locations using SQM LU DL, especially in Bangka Island. The data obtained from SQM is graphed so that it can be seen the transition from night to morning. The darker the sky, the higher the night sky brightness (NSB) level and the better as a place for astronomical observations. Results The darkest location is in the Bangka Induk area Bakam Village 22.24 mpsas and the brightest location is in the Ketawai Beach area, Central Bangka Regency with a NSB value of 16.54 mpsas. Areas with high light pollution have NSB of around 12 mpsas in the horizon direction, and 16 mpsas in the zenith direction. Areas with low light pollution have a NSB of around 17mpsas in the horizon direction, and around 20 mpsas in the zenith direction. Regression correlation between sky brightness and solar depression angle is 0.79 with depression angle range between 10.80 and 17.46 below horizon. The zenith direction SQM tends to have a deeper depression angle than the east direction
Keywords: Sky brightness, SQM, Solar depression angle
