For the sake of preserving your Religion take a moment to read this article :
Refuting the Reliance upon Calculations in Determining the Beginning and the End of Ramadan
Every year, a while before the beginning of the month of Ramadan, some statements and announcements are released which specify the day on which the blessed month of Ramadan starts. Similarly, several days before the end of Ramadan, they publish announcements declaring the last day of Ramadan and the day of ^Id al-Fitr. They argue that the reason for doing so is to maintain accord and unity among the Muslims and hence they rely on modern science. This argument is easily dismissed on the grounds that their actions provoke in reality more disagreement than unity among Muslims.
We hope those behind these announcements would stop for a moment and honestly ask themselves the following question: “Is it worth it to leave the sayings of the Prophet for the sayings of the astronomers and the like? Is unity achieved by relying on the statements of the astronomers and not by adhering to the teachings of the Prophet?” Naturally, the sound answer will be that the use of astronomy to determine the beginning of Ramadan for the purpose of achieving unity is absolutely unacceptable for in reality it caused confusion among Muslims before the beginning and the end of Ramadan for several years.
Our honourable Religion obliges us to command the obligatory and forbid the unlawful. It urges us to abolish the wrong and enforce the right. Nowadays, there are many who impart false judgements that have no correct religious foundation.
Let those who rely on astronomy and calculations to determine the beginning of Ramdan know that they have contradicted many sayings of the Prophet of Allah, peace be upon him. If the Muslim just reads the section on fasting in any of the famous books of Hadith, he will realise the obvious and blunt contradiction of those people to the Prophet. Also, one will be astonished and will question how this adverse group will face the Prophet on the Day of Judgement when they claim to have followed him, and yet they contradicted his Hadith and rejected it.
For those who seek the truth, the following are some of these explicit sayings of the Prophet, sallallahu ^alayhi wa sallam:
Al-Bukhariyy, Muslim, and others narrated from the route ^Abdullah Ibn ^Umar, may Allah raise his rank, that the Prophet, sallallahu ^alayhi wa sallam, said:
الشهر تسع وعشرون ليلة فلا تصوموا حتى تروه فإن غم عليكم فأكملوا العدة ثلاثين
This means: <> Although the Prophet made this clear statement, those who oppose said: “We are going to fast whether or not we sight the crescent, whether or not it is cloudy –as long as they were instructed by the astronomers!”
Imam al-Bukhariyy, Imam Muslim, Imam Ahmad, Abu Dawud and An-Nasa’iyy all narrated that the Prophet, sallallahu ^alayhi wa sallam, said:
إنا امة أمية لا نكتب و لا نحسب الشهر هكذا و هكذا
This means: <>.
Al-Qadi ^Iyad (544 AH), in his book ‘Ikmal Al-Mu^ilm Bi-Fawa’id Muslim’ explained the aforementioned Hadith by saying: “The Prophet did not mean that they were ignorant of which day was the twenty-ninth and which was the thirtieth nor he denied their knowledge of such calculations. Rather, he gave them a rule about observing the moon to begin fasting and to end fasting. By doing so, the Prophet did not allow them to adopt the methodology of calculation relied upon by the non-Muslims” [vol: 4, Chapter on Fasting, p: 14-15, Darul-Wafa’].