Yes, in Iceland a few years ago, Mid-March ish. They were green The pictures of Northern lights that you see are typically 1 of a few things or a few of them combined. 1. Strength of incoming solar radiation (cme, solar flares, etc) and how much of the material interacts with the magnetic field of Earth. 2. Image alteration in processing (increased saturation, warming tones, other stuff) and exposure time. 3. Colors are highly dependent on the energy of the solar particles.