ḤADĪTH OF THE DAY

“ The Prophet, peace and blessings of God be upon him said, "Gabriel led me in prayer at the house (1) two times (on two consecutive days). He prayed the noon prayer (2), the first time, when the shadow was the size of a shoe strap (the shortest shadow that could be observed). Then, he prayed the afternoon prayer (3) when everything was as long as its shadow. Then, he prayed the sunset prayer (4) when the sun set, the time when a fasting person breaks his [or her] fast. Then, he prayed the evening prayer (5) when the twilight disappeared. Then, he prayed the dawn prayer (6) when dawn broke, the time when food becomes prohibited for a fasting person. The second time, he prayed the noon prayer until the shadow of everything was equal to its length, the time at which he had prayed the afternoon prayer the day before (7). Then, he prayed the afternoon prayer when the shadow of everything was twice its length. Then, he prayed the sunset prayer at the same time as the day before. Then, he prayed the last evening prayer when one third of the night had passed. Then he prayed the dawn prayer when the earth shone with light. Then Gabriel turned to me and said, 'O Muhammad, thus was the timing (of prayer) for the prophets before you (8). The time [of each prayer] is between these two times (at which we prayed on each of the two days).'" Footnotes: (1) the sanctified house of God (al-Ka'bah) which is the most venerable structure in Islam, situated within in the Sanctified Mosque of Makkah. During prayer, Muslims face its direction, wherever they are in the world. (2) Second prescribed prayer of the day. (3) Third prescribed prayer of the day. (4) Fourth prescribed prayer of the day. (5) Fifth prescribed prayer of the day. (6) First prescribed prayer of the day. (7) He finished the noon prayer on the second day at the same time that he had started the afternoon prayer the first day. (8) i.e. The prayers of the prophets before you had extended times like these. ”

Sunan at-Tirmithiy كتاب الصوم باب ما جاء فى بيان الفجر

حَدَّثَنَا هَنَّادٌ وَيُوسُفُ بْنُ عِيسَى قَالاَ حَدَّثَنَا وَكِيعٌ عَنْ أَبِى هِلاَلٍ عَنْ سَوَادَةَ بْنِ حَنْظَلَةَ هُوَ الْقُشَيْرِىُّ عَنْ سَمُرَةَ بْنِ جُنْدَبٍ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم لاَ يَمْنَعَنَّكُمْ مِنْ سُحُورِكُمْ أَذَانُ بِلاَلٍ وَلاَ الْفَجْرُ الْمُسْتَطِيلُ وَلَكِنِ الْفَجْرُ الْمُسْتَطِيرُ فِى الأُفُقِ. قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ.
The Prophet, peace and blessings of God be upon him said, "Indeed, neither Bilāl's (2) call to prayer (3) nor the vertical dawn (4)should deprive you of your pre-dawn meal (1); rather it is the dawn which spreads along the horizon (5) (that signals the start of fasting)."
(1) Saḥūr: an optional, yet desirable, meal eaten before dawn by Muslims planning to fast that day. (2) Bilāl Ibn-Rabāḥ is one of the companions of the Prophet, peace and blessings of God be upon him, who is famous for calling for prayers in Madīnah. (3) The call to prayer (Athān) is a long call announcing the time of prayer. It is usually made up to twenty minutes before the commencement of prayer to give worshippers time to prepare for prayer; it is called even longer before the dawn prayer (Fajr), the first prescribed prayer of the day that takes place before sunrise. (4) The vertical dawn, also known as the false dawn, is indicated by rays that spread vertically in the sky. This occurs about twenty minutes before the true dawn. (5) The second dawn, also known as the true dawn, is indicated by a white line that spreads parallel to the horizon. The occurrence of the true dawn signals the start of the dawn prayer's time and, consequentially, the beginning of fasting.