A VERY informative article. As we know, a further eclipse is due on this date in 2018. July 27th for us and 15 Av on the Hebrew calendar. Reading this, it became apparent to me that this minor holiday is very apt to the Jewish people. It incorporated the allowing of the tribe of Benjamin to marry into the other Jewish tribes. If this hadn't been allowed, the tribe of Benjamin could have very well died out. There is also a small chapter emphasising the uniting of the tribes. It also celebrates the eventual forgiveness of the spies, by God, who were expecting to die on Av 9. It seems to be very Hebrew oriented - placing great emphasis of the uniting of the Tribes of Israel - the entry into the Holy Land etc.
My instinct tells me that this has to do with Israel alone. Tu B'Av I mean. That, perhaps, we Christians might not be here to witness this eclipse on 27th July. Maybe. This is well worth the read.The Meaning of Tu B'av