Solar flare

Initially my title for this picture was meant to be a joke.
I took the picture out of a velux window, which due to its location near the chimney, has lots of wee soot spots on it.
When I first saw the picture I assumed the 'solar flare' ar 10 o'clock was the sun reflecting on the soot somehow.

However having cropped the picture and zoomed in further, it actually looks like a solar flare.

I have another couple of pictures take a minute later through a different window, no solar flare but also no clouds near that area of the sky - this being my 2nd thought for the flare.

There is also a streak of faint light about 7 o'clock.

Can someone tell me what I'm seeing here?