Green orb caught over London, on March 2017

On March 25, 2017, a witness has caught an glowing orb like UFO over London, England. He didn't notice this object to the naked eye.

Witness statement:

I'm not actually sure what it is ( reason I came to you guys), to the naked eye I didn't notice it until I checked the photos. I was walking home from a friends and saw that the sunset at the time was unusual so I thought I'd get a couple of shots. There were no filters used at all. At first i thought it may have been a reflection or something like but I took three separate shots as I walked down the road n it's there in all of them?