Joe Deedon, president of TAC ONE Consulting, demonstrates searching for a shooter in a middle school during an Active Shooter Response course offered by TAC ONE in Denver April 2, 2016. According to TAC ONE, the course, which is offered for the first time to concealed weapons permit carrying civilians, is designed at preparing people to effectively save lives prior to the arrival of law enforcement at an active shooter incident. (Photo by Rick Wilking/Reuters)

Entertainment One is attempting to set the Guinness World Record for the longest chain of brides in one location at HMV, Oxford Street on March 11, 2012 in London, United Kingdom. The event was held to celebrate to celebrate the DVD release of The Twilight Saga: Twilight Breaking Dawn Part 1 (Photo by Dave J. Hogan/Getty Images)

These Northern Lights “rainbows” have turned the sky greener than the Earth below. Vitaly Istomin, 26, spent several nights in freezing conditions under the stars in northern Russia’s Khibiny Mountains to capture the aurora’s “rainbows”. (Photo by Vitaly Istomin/Caters News Agency)

Impressive images of these alien-like creatures were captured underwater – photographer Cai Songda is a keen diver and did not miss the chance to snap pictures of the unique “aliens”. Here: A Tremoctopus Gracilis in the waters around Anilao, Philippines. (Photo by Cai Songda/Caters News Agency)

The amazing gallery shows parts of London shot from above – and the views are breathtaking. Jason Hawkes, an aerial photographer from Reading, England, captured the images over the past six months while flying in AS355 helicopters. Here: The city of London at dusk. (Photo by Jason Hawkes/Caters News Agency)

12 vintage cars, 12 beautiful photos, captured and retouched by Stuttgart based photographer Mirko Frank, create stylish “Oldtimer Calendar”. Each car on photos has its own history and this history is also described in a few words in this calendar. Great calendar, don’t you think?

For his Behind a Little House Project Italian photographer Manuel Cosentino found an unsuspecting muse: a tiny nondescript house on an unexceptional hill. He returned to photograph the small building from the exact same location for nearly two years in order to capture the dramatic changes in weather and light that utterly changed the scenery just beyond the horizon