I was told that we do not practice Ashtanga Yoga on full moon days. I found out why:
The human body, similar to our planet, is affected by the gravitational pull of the moon. When the moon is full, blood is rushing through our bodies just like high waves take over beaches. We naturally feel energetic and emotional, but not well grounded. So we don’t need to do Yoga to energize us. The new moon, on the contrary, is when we feel calm but not energetic. So due to the natural stiffness, we are advised not to physically exert our body.