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

They did not see the new moon of Dhu’l-Hijjah – what should they do?

If he travels during Ramadaan to another country that started the fast at a different time, how should he fast?

If he starts fasting with a country that uses calculations, should he break the fast with them?

Every person who is resident in a country is obliged to start and end the fast with its people

A questioner is commenting on the previous answer about fasting and the hadeeth of Ibn ‘Abbaas about moon sighting with one witness

Ruling on fasting and breaking the fast of one whose testimony was rejected or who was not able to inform the authorities

The Muslims should cooperate in sighting the moon and informing the authorities

The Muslims are required by sharee’ah to be united in starting and ending the fast – and how that may be achieved

Shaykh al-Islam’s comment that the word hilaal refers to that which began and people saw it