From Shri K. Pattabhi Jois via the Ashtanga Yoga Shala:
"That day is very difficult day. Two stars one place (conjunction) is going. New moon also, full moon also. That day very dangerous day. You (take) practice (on that day), anyone can have a small pain starting. That pain is not going very quickly. Long time he is taking. Some broken possible. That is why that day don’t do." continue reading
