A PROTOTYPE OF TRUE DAWN OBSERVATION AUTOMATION SYSTEM

M Basthoni

Abstract

It requires adequate true dawn observation data both in quality and quantity to correct or verify the accuracy of the early true dawn criteria set by the Ministry of Religion of Republic of Indonesia, which in the last decade had been doubted by several parties. However, temperature and unfavorable field conditions present challenges in observing the true dawn. This paper describes the development of the True Dawn Observation Automation System which includes hardware and software requirements, system installation and performance testing in three locations: Karimunjawa (-5.78S, 110.48E, 1 m above sea level), Banyuwangi (-7.97S, 114.42E, 1 m above sea level) and Semarang (-6.97S, 110.29E, 15 m above sea level). An analysis of the data is also presented in this paper which includes the variability due to moonlight and light pollution on true dawn detection. The test results show that the system is running well but it needs upgraded GPS and Real Time Clock module so the system can work better. Meanwhile, analysis of the data recorded by the system shows that moonlight has a strong effect on true dawn detection in locations with low light pollution (Banyuwangi and Karimunjawa), an average difference of around 3.4° (13.6 minutes) compared to when moonlight was absent. Meanwhile, in areas with high light pollution (Semarang) it does not have a significant effect, an average difference of around 0.25° (1 minute). This study also proposes that true dawn is detected when the Sun's position averages -20 ± 0.2 degrees below the horizon.

Keywords

prototype; automated system; true dawn observations

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References

al-Bayhaqy, A. bin al-H. bin A. (1991). as-Sunan al-Kubro. Dar al-Kutub al-‘Ilmiyah.

Arumaningtyas, E. P., Raharto, M., & Herdiwijaya, D. (2011). Morning twilight measured at Bandung and Jombang. AIP Conference Proceedings, 1454(1), 29–31. https://doi.org/10.1063/1.4730680

Bahali, K., Samian, A. L., Muslim, N., & Abdul Hamid, N. S. (2018). Measuring the Sun Depression Angle of Dawn with a DSLR Camera. Sains Malaysiana, 47(11), 2877–2885. https://doi.org/10.17576/jsm-2018-4711-31

Bortle, J. E. (2001). Gauging Light Pollution: The Bortle Dark-Sky Scale. https://www.skyandtelescope.com/astronomy-resources/light-pollution-and-astronomy-the-bortle-dark-sky-scale/

Butar-Butar, A. J. R. (2018). Fajar & Syafak dalam Kesarjanaan Astronomi Muslim dan Ulama Nusantara. LKiS.

Dexter Industries. (n.d.). Run a Program On Your Raspberry Pi At Startup. Retrieved March 5, 2020, from https://www.dexterindustries.com/howto/run-a-program-on-your-raspberry-pi-at-startup/

Djamaluddin, T. (n.d.-a). Benarkah Waktu Subuh di Indonesia Terlalu Cepat? Retrieved December 5, 2019, from https://tdjamaluddin.wordpress.com/2017/09/13/benarkah-waktu-subuh-di-indonesia-terlalu-cepat/

Djamaluddin, T. (n.d.-b). Penentuan Waktu Shubuh: Pengamatan dan Pengukuran Fajar di Labuan Bajo. Retrieved October 1, 2020, from https://tdjamaluddin.wordpress.com/2018/04/30/penentuan-waktu-shubuh-pengamatan-dan-pengukuran-fajar-di-labuan-bajo/

Dogan, E., Ozbaldan, E. E., Shameoni, N. M., & Yesilyaprak, C. (2016). Automatic Rotational Sky Quality Meter (R-SQM) Design and Software for Astronomical Observatories. RevMexAA (Serie de Conferencias), 48, 31–32.

Hanel, A. & T. (2018). SQMDroid - A universal SQM measurement device. http://unihedron.com/projects/darksky/cd/SQM-LU/SQMDroid/Poster_ALAN2-2.1.pdf

Harijadi Noor, L. A. (2019). Analisis Perubahab Kecerahan Langit Waktu Fajar dengan Sky Quality Meter [Institut Teknologi Bandung]. https://repo.science.itb.ac.id/3597/

Herdiwijaya, D. (2016). Sky brightness and twilight measurements at Jogyakarta city, Indonesia. Journal of Physics: Conference Series, 771(1), 012033. https://doi.org/10.1088/1742-6596/771/1/012033

Herdiwijaya, D. (2020). On the beginning of the morning twilight based on sky brightness measurements. Journal of Physics: Conference Series, 1523(1), 012007. https://doi.org/10.1088/1742-6596/1523/1/012007

LAPAN. (n.d.). Mengenal Atmosfer. Retrieved November 4, 2019, from http://psta.lapan.go.id/index.php/subblog/read/2014/45/Pentingnya-Atmosfer-Bumi/mengenal-atmosfer

Lázaro, R. D. (n.d.). OBSOLETE Unattended Sky Quality Meter Station. Retrieved January 14, 2020, from http://rdlazaro.info/20-COMPU/80-RASPBERRY_PI/32-unattended_SQM_OLD.html

Michael. (n.d.). How To Setup Raspberry Pi Zero W Headless WiFi. Retrieved February 20, 2020, from https://core-electronics.com.au/tutorials/raspberry-pi-zerow-headless-wifi-setup.html

Nievas, M., & Zamorano, J. (2014). PySQM the UCM open source software to read, plot and store data from SQM photometers. http://eprints.ucm.es/25900/1/LICA_PySQM_v2.pdf

Noor, L. A. H., & Hamdani, F. F. R. S. (2018). The dawn sky brightness observations in the preliminary shubuh prayer time determination. Qudus International Journal of Islamic Studies, 6(1), 25–37. https://doi.org/10.21043/qijis.v1i1.2870

Rclone. (n.d.-a). Rclone - rsync for cloud storage. Retrieved March 1, 2020, from https://rclone.org/

Rclone. (n.d.-b). Rclone & Google Drive. Retrieved March 1, 2020, from https://rclone.org/drive/

Rclone. (n.d.-c). Rclone Install. Retrieved March 1, 2020, from https://rclone.org/install/

Remote.It. (n.d.). Installing remoteit on a Raspberry Pi running Raspbian or Raspberry Pi OS. Retrieved October 1, 2020, from https://support.remote.it/hc/en-us/articles/360045375151-Raspberry-Pi-Quick-Start-remote-itPi-SD-Card-image-

Rohmah, N. (2016). The Effect of atmospheric humidity level to the determination of Islamic Fajr/morning prayer time and twilight appearance. Journal of Physics: Conference Series, 771(1), 012048. https://doi.org/10.1088/1742-6596/771/1/012048

Saksono, T. (n.d.). Fajar Di Hari Dengan Polusi Cahaya Tertinggi. Retrieved October 10, 2020, from https://www.saksono.org/2020/08/fajar-di-hari-dengan-polusi-cahaya.html

Saksono, T., & Fulazzaky, M. A. (2020). Predicting the accurate period of true dawn using a third-degree polynomial model. NRIAG Journal of Astronomy and Geophysics, 9(1), 238–244. https://doi.org/10.1080/20909977.2020.1738106

Schnitt, S., Ruhtz, T., Fischer, J., Hölker, F., & Kyba, C. (2013). Temperature Stability of the Sky Quality Meter. Sensors, 13(9), 12166–12174. https://doi.org/10.3390/s130912166

Shaw, A. (n.d.). Working with the Raspberry Pi camera module. Retrieved March 5, 2020, from https://www.raspberry-pi-geek.com/Archive/2013/02/Working-with-the-Raspberry-Pi-camera-module

The Raspberry Pi Foundation. (n.d.-a). Installing operating system images. Retrieved March 5, 2020, from https://www.raspberrypi.org/documentation/installation/installing-images/README.md

The Raspberry Pi Foundation. (n.d.-b). Raspbian. Retrieved March 6, 2020, from https://www.raspberrypi.org/documentation/raspbian/

The Raspberry Pi Foundation. (n.d.-c). raspistill. Retrieved March 1, 2020, from https://www.raspberrypi.org/documentation/usage/camera/raspicam/raspistill.md

The Raspberry Pi Foundation. (n.d.-d). rc-local. Retrieved March 5, 2020, from https://www.raspberrypi.org/documentation/linux/usage/rc-local.md

ThomasJ1. (n.d.). Wireless All Sky Camera. Retrieved August 1, 2020, from https://www.instructables.com/Wireless-All-Sky-Camera/

Ubuntu. (n.d.). Mencoder. Retrieved March 2, 2020, from https://help.ubuntu.com/community/MEncoder

Universidad Complutense de Madrid. (n.d.). PySQM. Retrieved February 10, 2020, from https://guaix.fis.ucm.es/PySQM

Zamorano, J., García, C., Tapia, C., Sánchez de Miguel, A., Pascual, S., & Gallego, J. (2017). STARS4ALL Night Sky Brightness Photometer. International Journal of Sustainable Lighting, 18(35), 49–54. https://doi.org/10.26607/ijsl.v18i0.21

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