I'm a high school yearbook photographer. I was photographing a girl's varsity soccer game at Saddle Brook NJ high school. During down time I was looking up at the sky and noticed a contrail of a jet, but couldn't see the jet itself. I zoomed out with my 300mm lens to take a pic of the jet. It was flying at a very high altitude. I put the camera in manual focus mode. This is something you have to do when photographing high flying objects. I took a couple pictures. I zoomed in on my Nikon D7100 LCD display to look at the jet when I noticed there was something in front of it. (The jet was flying in a westerly direction) I took some more photos trying to get the object in frame. I could not see it with my eye. I needed the 300mm lens trying to see it. I took several pics. I looked at the display on my Nikon, zooming in to try to determine what the object was. I was baffled. I pointed my camera skyward and could not find the object again. It was gone. At home I looked at the silhouette of the jet. I noticed it had squared wings. I looked at some stock U2 photos. It looks like a U2. I have 10 pics of the jet and the object. I will attach some highly zoomed in photos for you. I've been a sports photographer for 8 years. I am very camera savy, I know my cameras. Whatever this is, it baffles me. I was sitting by myself, behind the goal during the game. The field runs east/west so I had to sit at the western edge to have the sun at my back for the photos. I don't know if anyone else saw it, it was very high and impossible to see with the unaided eye. I was freaked out when I saw what I had captured on my camera.