A blood red Moon hovers in between the steam-choked skyscrapers. This isn't the apocalypse, but as any resident of Calgary will be all too happy to you, it's the next best thing: it's the Moon rising over Edmonton.

So just how did Edmonton get the remarkable combination of a low, crimson Moon and steam rising all around its buildings? It's all a clever mix of carefully chosen angles, some scatter light, and - predictably enough - some fiendishly cold temperatures. Here's NASA's explanation:

The above image was taken two weeks ago as the full Snow Moon started to rise above Edmonton, Alberta, Canada. The odd coincidence between the angular size of the far distant Moon and the angular width of nearby buildings created a striking juxtaposition. Backing away from the buildings so to reduce their angular size was a key to planning the image. The temperature was so low, -25 C, that plumes of steam rose from neighboring oil refineries. The above image was taken during a momentary break in the plumes. The rising Moon appears red here for the same reason that a setting Sun appears red — because blue light is preferentially scattered away by intervening air. In this case, the shimmering steam plumes likely also caused the Moon to appear slightly compressed.