The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

By making use of digital colour grading and composites, Romanian photographer Caras Ionut created these dreamy blue-themed landscapes. The work is even more impressive when you consider that Caras, who has been a mariner for the last 24 years, only picked up an interest in photography a few years ago. For more of his work, including fashion composites and semi-surrealist scapes.

Pfc. Sebastian Rodriguez, machine gunner, Weapons Platoon, Lima Company, 3rd Battalion, 3rd Marine Regiment, Marine Rotational Force – Darwin, fires an M240 machine gun during a night squad-attack exercise, here, May 22, 2013. (Photo by Sgt. Sarah Fiocco/U.S. Marines)

It's that time of year again when dogs with unusually large heads, hairless bodies and other oddities compete to be the World's Ugliest Dog. This year's winner? A 2-year-old mutt named Peanut, whose wild white and brown hair, bulging eyes and protruding teeth belie his sweet, energetic personality. Peanut's owner, Holly Chandler of Greenville, North Carolina, says he was seriously burned as a puppy and she wants to use her pet to raise awareness about animal abuse. She plans to use the $1,500 prize to pay for other animals' veterinary bills. The contest, held at the Sonoma-Marin Fairgrounds in Petaluma, California, is in its 26 year. The dogs are scored by a three-judge panel in several categories, including special or unusual attributes, personality and natural ugliness.

Sgt. William Olas Bee, a U.S. Marine from the 24th Marine Expeditionary Unit, has a close call after Taliban fighters opened fire near Garmsir in Helmand Province of Afghanistan, May 18, 2008. (Photo by Goran Tomasevic/Reuters)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)

U.S. Marine Lt. Ben Reid from 1/2 Charlie Company of Task Force Tarawa waits to be medivaced after being hit with shrapnel and a machine gun round, in the southern Iraqi city of Nasiriyah, on March 23, 2003. The Marines suffered a number of deaths and casualties during gun battles throughout the city. (Photo by Joe Raedle via The Atlantic)