Once again I have acquired two coins related to one another. They are both Septimius Severus AE coins from Nikopolis showing Crescent Moon and Stars. The first is an AE17, BME 27 struck between 193-211 AD:

OBV: AV KAI CE CEVHPO, laureate head right
REV: NIKOPOLITWN PROC ICTRO, crescent and one star
The second I have attributed as an AE18, Varbanov 2554, struck in the same time period.

OBV: AY K L C CEVHROC, laureate head right
REV: NIKOPOLITWN PROC ICTR, Crescent and three stars
While I am no expert on the symbolism of these coins, I found a few references on line.
Quote:
The crescent and star symbol is one of the most ancient designs. It appears on petroglyphs and steles of the first civilization in Sumer. This symbol was adopted by the Greeks and was associated with many of their gods including: Selene and Helios, as one would suspect, but also with Artemis of Perge, the Artemis of Ephesos, the Aphrodite of Paphos, Zeus Casios, the Zeus of Tarsos, Nemesis, Tyche, and Astarte.5 It is not surprising that this symbol found its way onto Greek and Roman coins. Often times the stars and crescent were presented on the same coin. Typically, the crescent symbol is associated with the moon and the stars with the planets.
This same article indicated the symbolism may have something to do with an eclipse or even a partial eclipse.
Quote:
It is not clear from ancient texts whether these were total, annular, or partial. Totality in an eclipse is seen over a short swath of the Earth with a width often less than 250 kilometers. Still, a partial eclipse would have an enormous impact on ancient viewers. Just before and after totality the sun's rays penetrate through the moon's valleys to create a short star burst effect prior to the sun disk's reappearance.