Glowing UFO caught in Midland, Texas

On October 27, 2016, during sunset, a witness was in office in Midland (Texas, USA) when he photographed a glowing green UFO in the sky. He didn't see it. What is it?

Witness statement:

-I was in office that has window facing west.
-I took a photo with Samsung cell phone of sunset; did not see anything unusual at the time of photo, neither did coworker.
-Reviewed photo approximately three days later, noticed the green sphere towards top of photo.
-A clipped portion of photo of only said green object also attached.
Also, anonymity will be removed once my military status changes.

Thank you. Rene