There is nothing wrong with sighting the moon by means of modern instruments

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Check below answers in case you are looking for other related questions:
If they did not find out that the month of Ramadan had begun until partway through the day, what should they do?
Is there a certain length of time that the new moon has to be in the sky?

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Related Answers:
It is permissible to use telescopes etc., but not calculations, to sight the new moon
If he follows the moon sighting from another country, is it acceptable to delay the Eid prayer so that he can pray with the people in his country?
Ruling on fasting and breaking the fast of one whose testimony was rejected or who was not able to inform the authorities
If they did not find out that the month of Ramadan had begun until partway through the day, what should they do?
Is there a certain length of time that the new moon has to be in the sky?

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