The criteria used by the Islamic Society to determine the beginning and end of Ramadan, and the two Eid celebrations is listed below.
1. Islamic Society will accept duly verified reports of crescent sighting from anywhere in North America.
2. All reports of naked-eye sighting of the crescent must be verified by experts with knowledge of Islamic rules and regulations in this matter and aided by astronomical information.
3. If the sky is clear, the concept of Jamme Ghafeer (a large number of witnesses) shall be used to authenticate reports of crescent sighting.
4. If the sky is overcast, expert testimony shall be essential and over-riding unless validated by Jamme Ghafeer.
5. If astronomical data suggest that it is improbable to sight the crescent on a given day, Jamme Ghafeer shall be employed to reach a decision.
6. May Allah help us and guide us. Ameen.
Sources:
1. Hadith in which Abdullah b. ‘Abbas (RA) did not accept the sighting of moon in Syria to start the month in Medina, stating that it was not what the Prophet (SAW) had taught them.
-Sahih Muslim – Book 6, Hadith 2391
Hadith Location: https://sunnah.com/muslim/13/34
2. The opinion linked below was internationally agreed to by some of the most senior international scholars of Islamic countries at an international fiqh meeting and declaration in Mecca 1981. The grand mufti of Saudi Arabia, then Sheikh Abdul Aziz Bin Baaz, also signed it with other major international Scholars from all schools of thought (countries).
-Sheikh ibn Baz, Saudi Arabia
Fatwa: http://www.utahmuslims.com/wp-content/uploads/2019/06/MoonSightingFatwa1981.pdf
Other Sources Online
1. “There are efforts to standardize the Islamic Calendar so that Ramadan is started on the same day in various communities. But the relationship of celestial bodies to the earth is a living thing and every location has its own sky.”
-Sheikh Hamza Yusuf
Exact Location of video: https://youtu.be/fXdjE57w69o?t=146
Full video: https://www.youtube.com/watch?v=fXdjE57w69o
2. “…people of that area should see, their own moon..”
– Dr. Zakir Naik
Exact location of video: https://www.youtube.com/watch?v=mAdeyo6Ce44&feature=youtu.be&t=108
Full video: https://www.youtube.com/watch?v=mAdeyo6Ce44
3. Hadith of people in Makkah and people in Shaam fasted on different days. Each area had their own moon sighting.
– Sheikh Assim Al Hakeem
Exact location of video: https://youtu.be/bclqOtiHAOI?t=19
Full video: https://www.youtube.com/watch?v=bclqOtiHAOI
4. An explanation of local moonsighting i.e. Morocco vs. Saudi Arabia
Exact location of video: https://youtu.be/6WalY8up8_8?t=44
Full video: https://www.youtube.com/watch?v=6WalY8up8_8