When does Suhoor (a meal taken before fajr in the month of Ramadan) end?

Talk b. Ali (may Allah be pleased with him) tells:
The Messenger of Allah stated:
Do not let the fajr al-kazib (the false day break) prevent you from eating or drinking so eat and drink until fajr al-Sadiq, (the true daybreak) till the true fajr appears. (Abu Dawud, Sawm: 17; Tirmidhi, Sawm: 15)
According to the relation of Bukhari and Muslim from Ibn Mas’ud (may Allah be pleased with him), the Messenger of Allah said “It is a brightness seen as horizontal, but not vertical” when he was describing “the true fajr.” (Bukhari, Adhan: 13, Talaq: 24, Khabar al- Wahid: 1; Muslim: Siam: 40)
Fajr means dawn time. It indicates the time Suhur ends and the Morning Prayer can be performed.
The false fajr is a light brightness seen vertically when close to morning in the horizon and which is visible only for a short time. That brightness disappears and after 20-25 minutes, then the true fajr appears. That time, a horizontal brightness among the horizon line appears. That brightness is also called “breaking of the day.”
Thus, the Prophet (pbuh) advices not to esteem the first brightness seen in the horizon.
The time taking place in the daily calendars and known as “imsaak” is the time of the true fajr. Adhan for the Morning Prayer is called at that time. In this way, both the time of imsaak begins, fasting starts and salat al-fajr is performed.
- When does Suhur end?
- How did people determine the time of imsak in the past? I heard from old people that they determined the time of imsak when it became bright enough to distinguish black thread from white thread. However, it is very dark at the time of imsak.
- Will you explain the statement "eat and drink, until the white thread appears to you distinct from the black thread..." mentioned in verse 187 of the chapter of al-Baqara? How will people living at the poles perform fasting?
- The duration of suhur (a meal taken before fajr in the month of Ramadan) and the time of the morning prayer
- The duration of Suhur and the time of the Morning Prayer
- Time of iftar (breaking of fast)
- RULES AND REGULATIONS FOR FASTING
- The Times of Prayers
- How should the person who realizes when he wakes up that he is junub (ritually impure) continue with the fasting? Does getting blood drawn invalidate the fast?
- How should the person who realizes when he wakes up that he is junub (ritually impure) continue with the fasting? Does getting blood drawn invalidate the fast?