What do you think this might be?
The brightening in the contrail was in the right place for a 120 degree parhelion. When I first saw it, it was extremely bright and then faded over the period of two or three minutes. These images were taken towards the end of the observation period. If this is not a 120 degree parhelion what else could cause such a local brightening in a contrail?
Thanks in advance for any suggestions,