9
votes
2answers
339 views

Polyphasic Sleep and Halacha

I recently read an article on polyphasic sleep and I'm quite interested in experimenting with it. The article advises the Uberman approach which advocates 20-30 minute naps every four hours, meaning ...
2
votes
1answer
422 views

Does one make Birkas Hatorah/Hashachar before alos hashachar?

As per this question, it seems apparent that one doesn't make the morning blessings until at least alos hashachar. However, in Rabbi Avraham Greenbaum's book "The Sweetest Hour: Tikkun Chatzot," on ...
5
votes
1answer
2k views

Last time for Kiddush Levanah

How can I calculate the last possible time to say Kiddush Levanah for a given month?