This photo is on Steve Albers site, who works for a US gov site called NOAA (National Oceanic Atmospheric Administration).
As I looked at the photo, it was clear that the edges had been blurred, however the middle was clear as day and there seemed to be a crater edge with a structure. As I added light to bring out the detail, I found that it was a dome built in the crater. 30% of the dome was solid metallic and 60% was a forcefield.
Remarkable and strange. Funny how structures are so different from what we expect from the movies. Hollywood over estimates the artistic side of alien ships, buildings, structures...but the truth about it is that most alien structures are made for a specific use, rather than their aesthetic appearance.