whens the latest i can say kriyas shema al hamita????

A lubavitcher Maggid shiur once told me that if you wake up and realize you forgot krias shema you should close the shades and pretend it’s still night time.

Till Alos Hashachar.

You must say Krias Shema before Chatzos. Assuming you did that already (by davening Ma’ariv after Tzeis, or if you davened Ma’ariv at shkiah then by repeating Krias Shema some time after Tzeis), then you can say Krias Shma al Hamitah as late as you want until I assume Alos HaShachar.

ItcheSrulik, why close the shades? Isn’t closing your eyes enough?! Or when you say Shma, you cover your eyes with your hand. Now its dark!

There is a website called myzmanim that gives you all the times. Basically, you must say Krias Shema after Tzeis HaKochavim (when the stars come out). The minhag is is that this is 42 minutes after shkiah- sunset (that’s an hour after candle lighting on Erev Shabbos- though in reality Tzeis is probably earlier). You also must say Krias Shema before Chatzos (midnight… but the halachic midnight, it’s not always 12 AM). Assuming you did all that, then you should also say Krias Shema before you go to sleep however late it is (presumably until Also HaShachar- dawn). If you forgot to say Krias Shema before Chatzos, say it as soon as you remember, don’t wait until you go to sleep. Then you could say Krias Shema again before you go to sleep.

what if one works the night shift and goes to sleep in the AM. can they say the bracha with krias shema?

Yenting: Unless anyone can find a source otherwise, I don’t think you can say the Bracha that night (well, I have a reason that you can but no one says it Lema’aseh).

Harotzeh: Of course. That’s an explicit Gemara (Brachos 8b maybe?).

Havarka: June 21st is always the longest date of the year but does not always start the earliest. Also, if you used myzmanim for those times they are incorrect. Those are a Chumra against the majority of Poskim. The Shulchan Aruch clearly states that Alos is 72 minutes before Neitz. There is no reason to add at least an extra half hour like they do. (Also, I assume those are times for New York but you should have stated that.)

Havarka: Not a source. A S’vara. The S’vara is true and stated explicitly in the Aruch Hashulchan. But none of the Poskim apply the S’vara far enough to allow this conclusion. Thus, Lema’aseh, the S’vara is the reason for it but does not quite apply all the way to its logical conclusion. (Someone once said that applying S’varas all the way to their logical conclusion or not is the difference between a Lamdan and a Halchist. I think that’s true. And since this is a Halachic issue, we cannot apply the S’vara to where the Poskim haven’t.)