After the Battle of Shiloh, soldiers both dead and alive were left on the battlefield overnight. Some were visible by the blueish-green glow which emanated from their wounds.
Those soldiers who glowed ended up with faster healing times and less hospitalization than their non-glowing counterparts. No one knew why, so it was attributed to God's intervention. The glow was called "Angel Fire."
It happened again in WWI, in France, where the nights were as cold as those in Tennessee. There was still no explanation for the phenomena. It has remained a mystery all along--until now.