In Arabic astronomy is the knowledge of stars. Stars is called is Najam and Najam is plural word. They have two kinds one kind is rigid and second is wondering. God has established stars for the beauty of sky and with their walk days and nights are denoted.

Chang of weathers and months, weeks and years and their times are known. Their explanation is in Quran. The verses of Quran are as translated that we inter the day in night and also the night in day. And sun and moon are for capture (Al Quran).

Think the calculation of years by sun and moon. Wondering stars are not all stars but they are in fixed counting.

At the bares of practical to precast something is separates from the knowledge of vanishes.
As some teacher knowing the ability of his students he says that this student will get through examination. Either he passes or fails music what had said he said according his experience. As some lower says his assistant that we may win the case this year. Decision is whatever but there procedure is according to law. Which is not counted in any way. In some crime after its failure as the Ulam-e-Karam published this views according to their experiment. They divide published material that in some place mauluna will address if Mulana cannot reach their he is not guilty for it. As the table of railway trains is republished. But some time that time take fails railway department is not guilty for that. As it the precaution of astrologist can be wrong as the astrologist precautions are based upon those experiments. The precaution may be wrong which is as possible.

Because of the levels their value is known and indeed the man who has better knowledge of these things he can explain letter about them and that agency the value these things better and the other man cannot do it. If he will try to do so he will be on wrong and its impressions will be negative.

The man who has this knowledge is known as jewelers and for it example is famous that value of a stone is known by a jeweler. As the value of diamond stone is known by a jeweler.