The Jewish community of Ostroh (in what is now western Ukraine) was miraculously spared when a Russian army led by General Suvorov attempted to breach its walls, claiming Polish insurgents were present inside. To commemorate the miracle, the day of 7 Tammuz was established as a local day of rejoicing, and a special scrollin which the story was inscribed was read each year on this date.
According to legend, two cannons that struck the great Maharsha synagogue caused no harm. The two cannons were thereupon displayed in the synagogue for all to see. (Yalkut Volhynia,issues 2–3)
Link: Other Purims
During the summer months, from the Shabbat after Passover until the Shabbat before Rosh Hashahah, we study a weekly chapter of the Talmud's Ethics of the Fathers ("Avot") each Shabbat afternoon; this week we study Chapter Five.
Once a month, as the moon waxes in the sky, we recite a special blessing called Kiddush Levanah, "the sanctification of the moon," praising the Creator for His wondrous work we call astronomy.
Kiddush Levanah is recited after nightfall, usually on Saturday night. The blessing is concluded with songs and dancing, because our nation is likened to the moon—as it waxes and wanes, so have we throughout history. When we say this blessing, we renew our trust that very soon, the light of G‑d's presence will fill all the earth and our people will be redeemed from exile.
Though Kiddush Levanah can be recited as early as three days after the moon's rebirth, the kabbalah tells us it is best to wait a full week, till the seventh of the month. Once 15 days have passed, the moon begins to wane once more and the season for saying the blessing has passed.
Links:
Kiddush Levana: Sanctification of the Moon
Brief Guide to Kiddush Levanah: Thank G‑d for the Moon!