Flash in Orion

I was imaging Orion when I captured this shot. Still trying to work out what it was. It was taken from Inverness, Scotland on 16th February, 2015 at 21.04UT.

Below are some other shots I took the same night.

M42 using 300mm lens

M42 using Nexstar 4SE

Flame Nebula using 300mm lens

All images taken with Canon 1100D, stacked in DeepSkyStacker and processed in StarTools and Krita.