The rationale for the salat timesheet

Introduction City life and the many occupations have led communities of Muslims to make use of time sheets and schedules marking the timing of salawat.
In them, two fields that were familiar from post-classical antiquity have been made to coincide, with greater or lesser fortune, fiqh and astronomy.
As is well known, belief fostered scientific knowledge-particularly mathematics and astronomy-in a healthy relationship that is difficult to recognize today. The fiqh and its interpretation In the fiqh – we focus here on the maliki – the entry of the moments of the salat is well specified: -) Fajar: moment when the first sign of brightness begins to be perceptible in the environment by the dawn, and ends shortly before sunrise.
– Duhur: moment immediately after the one marked by vertically placed objects having their minimum shadow in the day.
-) Asar: time when the shadow of vertically placed objects measures equal to the minimum shadow plus the length of the object.
– Magrib: moment when the sun’s corona is hidden by the horizon, although the luminous effects of its rays remain in the surroundings.
– Isha: the moment at which all traces of sunlight disappear from the crespusculum. Mathematical interpretation The main problem in interpreting the fiqh mathematically arises from conceiving the concept of twilight, light scattered by refraction in the atmosphere before sunrise (dawn) and after sunset (dusk).
Twilight has been associated with solar depressions of 6 (civil), 12 (nautical) and 18 (astronomical) degrees. The time of the fajar (respectively isha) is marked by reaching astronomical twilight and decreasing (respectively growing), although different solvent groups of Muslims have adopted other criteria for the angle varying the choices between 15 and 19.5 degrees, even distinguishing in the use of the angle depending on whether it is the isha or the fajar.
In Grenada, for example, the angle of 18 degrees is used for both times, as it is at the University of Islamic Sciences in Karachi.
The ISNA (Islamic Society of North America) sets it at 15, indifferently.
The calculation of sunset and sunrise is very delicate, as it is influenced by many factors that are difficult to weigh: shape of the horizon, nature of the coordinates considered (topocentric versus geocentric), influence of the refraction of light (depending on the density of the atmosphere), height of the place, extension of the area of validity of the calculations, orography of the area, etc.
In most cases topocentric coordinates are taken for the calculation, light refraction is included for an apparent sunset and the height of the highest place in the area of validity is taken into consideration.
The calculation of the duhur and asar times has no difficulty and is free of controversy, regardless of the guideline of the school followed. The use of the time table When there is a time table with the characteristics explained above, as in the case of the city of Granada (Spain), it must be used carefully.
The main guidelines explained by times of salat are the following: -) Fajar.
It has been observed that calculated with the astronomical twilight much fidelity is obtained.
Without going any further, a few moments later the din of the birds is born as they begin their daily activity.
From that moment on, the prayer can be made and one can stop eating some time before it in Ramadan.
We believe that this angle is ideal.
The fajar prayer should not be postponed to the calculated time of sunrise, as the sun will have risen although the visibility of the crown will depend on the irregularities of the horizon.
-) Duhur.
Most theorists and calculation recipes put the entry of this time at five minutes of the astronomical noon of the place.
It is a long prayer time.
-) Roasting.
Prayer can be performed at the time fixed by the calculation.
-) Maghrib.
In the assumptions referred to above for the calculation of maghrib, one may offer the maghribprayer at the calculated time and also break the fast.
In any case, in the matter of sunset, we can never be pessimistic enough, given the enormous complexity of the above-mentioned calculation. -) Isha.
We are inclined to consider that the moment of the isha and the fayar are symmetrical and should be calculated by the same angle of 18 degrees.
However, from experience, we do not consider the asymmetry in the calculation to be unreasonable: consider for the fayar the angle of 18 degrees and for the isha the angle of 17 degrees.
This means that the isha would be somewhat advanced.
In any case, the prayer of this moment can be made immediately when the time fixed by the calculation arrives. General Considerations Any time table for prayer is a mere advice, which would be subject to the worshipper’s observation.
However, a well-made table should not be underestimated because of its unifying value.
The one who uses a table should make previous inquiries about different aspects of its elaboration.
A table that does not take into account the refraction of light as a calculation factor for the magrib should be discarded, especially if it does not take into account the height of the place.
This last feature would be enough to rule it out.
It makes no sense to use a valid sheet in an area of a few square meters; should each neighbor have his own?
The use of the leaf should be detached from the attitude of compulsion, especially in Ramadan.
Especially in this month it should never serve as a controversy what is accepted without it throughout the year.
Yahya Garcia.
Yahya Garcia is a Doctor of Science from the University of Granada, specialized in logic, professor of mathematics for computer science, programmer and translator from Arabic into Spanish.
He is an astronomy and observation enthusiast.