Until how late in the day may a person recite the Minha prayer?
At first glance, it would appear that the final time for reciting Minha is "Sheki’a," or sundown, and this is indeed the view of the Mishna Berura (commentary by Rav Yisrael Meir Kagan of Radin, 1839-1933). The Mishna Berura rules that if a person has the option of praying Minha privately before sundown, or praying Minha with a Minyan after sundown, he should pray privately before sundown. Since, according to this view, sundown marks the final time for praying Minha, one must recite Minha before that point, even at the expense of congregational prayer.
Others, however, disagree, and claim that one may, if necessary, pray Minha even after sunset, during the period of Ben Ha’shemashot ("twilight"). This was the position of Hacham Ben Sion Abba Shaul (Israel, 1923-1998), and he calculated Ben Ha’shemashot as extending for 26 minutes after sundown. Hacham Ovadia Yosef similarly allows reciting Minha during the period of Ben Ha’shemashot, but he does not accept Hacham Ben Sion’s calculation. In his view, Ben Ha’shemashot extends for only 13.5 minutes after sundown, and this is the ruling we follow. Therefore, a person who did not recite Minha before sunset may still recite Minha, as long as 13.5 minutes have not passed since sunset. By the same token, a person who has the option of reciting Minha privately before sunset or with a Minyan after sunset should recite Minha with the Minyan, assuming they pray before 13.5 minutes after sunset.
May a person recite Minha if he knows that he will be unable to complete the Amida prayer before the final time? For example, if a person realizes at exactly 13 minutes after sunset that he has not yet prayed Minha, may be begin praying at that point, realizing that most of his Amida prayer will be recited after the final time for Minha, which occurs just 30 seconds later?
This issue is subject to debate among the Halachic authorities. The Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909), in one place in his writings, rules that one should not begin the Amida if he will be unable to complete the prayer before the final time. Elsewhere, he writes that the majority of the Amida must be recited before the final time, and therefore one may begin praying the Amida if he will be able to recite most of the prayer before 13.5 minutes after sunset. Hacham Ovadia Yosef, however, rules that it suffices to begin the Amida prayer before the final time. As long as 13.5 minutes have yet to pass since sunset, one may begin the Amida, even if the majority of the Amida will be recited after this point. Thus, a person who remembers even 12 or 13 minutes after sunset that he has not recited Minha should recite the Amida at that point.
Summary: The final time for reciting Minha is 13.5 minutes after sundown. One who remembers he has not recited Minha anytime before that point should begin the Amida, and he fulfills his obligation even though the majority of the Amida is recited after that point, since he began the Amida in time.
