Accuracy of Solar Azimuth Calculation with Aproximate Solar Coordinate (ASC) Algorithm as a Reference for Determining Qibla Direction
M. Ihtirozun Niam (a), Ahmad Syifaul Anam (a)

a) Universitas Islam Negeri Walisongo Semarang
Jalan Prof. Hamka (Kampus III), Ngaliyan, Kota Semarang 50185, Indonesia
*ihtirozun_n[at]walisongo.ac.id

Abstract

The reference that is often used in determining Qibla direction is the Azimuth of the Sun. Apart from being bright and large in size, the Sun quantitively is seen more often than any other celestial body. It is just that to get accurate solar data requires a fairly long calculation algorithm with corrections for more than 2000 step like the one in the Variations Seculaires des Orbites Planetaires (VSOP 87) algorithm. This article offers a relatively short algorithm with a correction less than 10 step but obtains accurate Solar azimuth results. The author uses an exploratory method with a comparative approach where the author explores the azimuth value of the Sun both before culmination and after culmination, seen from places in the southern and northern latitudes and at the solstice and equinox times, then compared with the Sun data calculated by VSOP 87 algorithm. The result is the difference azimuth value of the Sun between the ASC algorithm compared to VSOP 87 lest than1 arc minute, so it is still relatively accurate to use in calculating solar data as a reference for determining the Qibla direction.

Keywords: Solar Azimuth- Aproximate Solar Coordinate (ASC) Algorithm- Qibla Direction

Topic: EARTH, ATMOSPHERIC, AND SPACE SCIENCE