A strange contraption with illuminated portholes appears to be floating over the pier of Brighton, Great Britain. In reality this UFO is just another example of "mirror ghosting", a photographic reflection by which a mirror image of a bright light source (in this case the bright windows of the building on the pier) pops up in another part of the picture, with the image centre as the point of symmetry. The flare in this example was caused by a protective filter.
[© Arthur HOOD - more info on Mr. HOOD's picture and on photographic optics in general can be found at www.toothwalker.org]