The reddish glow is caused by sunlight scattering in the rapidly expanding
exhaust plume at orbital altitude. At this moment, the rocket stage
was in Earth’s shadow while the plume remained sunlit, creating a high-altitude
optical display visible across much of Northern Europe.

A red spot over the valley (at about 19:45 local time), it was caused by a Falcon 9 rocket from SpaceX. Location: Ørsta, Norway. Details: Canon 650D, fisheye lens (8mm).