by the U.S. Air Force, Maryland,
September 1954, Daytime
The photo was taken by a U.S. Air Force test pilot:
http://ufologie.net/htm/b57canberra.htm
The UFO was photographed purely by chance and was not discovered until the photograph was developed.
Judging from the original photo (before it was manipulated) – it’s obvious that the unknown object is a flying craft of some sort.
So why has the photo been manipulated (see the below photos)? And who has given the order to manipulate it?
This UFO case proves which important and outstanding work the top UFO researchers (here NICAP's adviser Ralph Rankow) were (are) doing.
NICAP's photographic adviser Ralph Rankow, a New York photographer, investigated the image in 1964, and wrote (from the above article by ufologie.net):
"No one actually reported seeing with their own eye the saucer-like object in the upper right portion of the picture. Even so, the object evoked such curiosity that another flight was reportedly made over the same area to look for ground reflection that may have caused it – although I understand none were observed.
A close scrutiny of the B57 photo shows the trees, bushes and houses all casting long shadows, but the object throws no shadow on the ground whatsoever. Moreover, (and this point is very important), the dark parts of the object are much too strong to be so far away. As the trees, bushes and houses get farther away, the haze cuts down their intensity and contrast. And the wooded area in the distance directly behind the object is fuzzy and weak by comparison with the strong highlights and shadows of the UFO itself.
In my analysis report to NICAP, I also pointed out that the object obviously had dimension. Its pattern of light and shadow is consistent with the rest of the picture, with the sun low and coming from the left. The object is also symmetrically shaped and contains all tones of gray, from white to black."
The above article mentions that there is some confusion whether this photograph was taken over Maryland or the Edwards Air Force Base in California. But judging by the landscape, it seems that the photo was taken over Maryland. The photo was taken in 1954 and not in 1957, as mentioned in several articles.
Wikipedia: Edwards Air Force Base, California:
http://en.wikipedia.org/wiki/Edwards_Air_Force_Base

(Ufologie.net photos)