"We have not created the
heaven and the earth and all that is between them in mere idle play.
None of this have We created without an inner truth: but most of them
understand it not. "
"...He created the sun, the
moon, and the stars (all) governed by laws under His commandment."
It is truly remarkable that the Qur'an revealed between 610 and 632 CE contains in it scientific knowledge that has taken centuries to be discovered. The only explanation for this is that without a doubt, it is divine in origin. We Muslims believe that the Qur'an, in original Arabic, is the actual word of Allah, the Most High. A proper understanding of the Qur'an therefore also requires an understanding of the worlds about us.
If there is any religion that invites man to the study and understanding of the heavens, it is Islam. An understanding of the discipline of astronomy is essential for the appreciation of the religion of Islam. No other religion uses or relies on the heavens and the motion of the moon and sun for time keeping and calendars as Islam does. Allah created this tremendous universe that we live in and we are invited to reflect upon it, to understand it so that we may be able to practice our religion with conviction based on reason to the best of our abilities.
"And it is He who ordained
the stars for you that you may be guided thereby in the darkness of
the land and the sea."
If you become familiar with the constellations and the stars in the sky, one can never be lost anywhere in the world. They are truly a guiding light in the canopy of the heavens. You can be anywhere in the world and immediately on looking up in the night sky and by recognizing stars, you can know what latitude you are at and where is north and thereby all the other directions. You can know what time of the year it is in the absence of any calendars. It is rather appropriate that the crescent moon and star is used as signs to represent matters of religion among Muslims.
The moon and the sun are of vital importance in the daily life of every Muslim. Using the moon, Muslims determine the beginning and the end of the months in their lunar calendar. By the sun the Muslims calculate the times for prayer and fasting based on the position of the sun in the horizon. It is also by means of astronomy that Muslims can determine the precise direction of the Qiblah, to face the Ka'bah in Makkah, during prayer.
"They ask you about new crescent
moons, say they are but signs to mark fixed period of times for mankind
The subject of crescent visibility has been studied in modern times by Prof Ilyas from Malaysia who has developed several visibility criteria and the concept of the International Lunar Date Line (ILDL). Ilyas's main criterion depends on the moon's altitude (in degrees) above the horizon at sunset and the moon's angular distance from the sun (relative azimuth) at sunset. If a moon's altitude and relative azimuth are greater than certain threshold values, then the moon is likely to be visible. The ILDL is a curved line on a world map which separates areas (west of the line) where the crescent is likely to be seen at the start of the lunar month from areas (east of the line) where the crescent is unlikely to be seen. The probability of sighting the crescent increases as one travels west of the ILDL and diminishes as one travels east of the ILDL. Unlike the solar date line which has a fixed position, the position of the ILDL moves from month to month.