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)

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 truck is seen in a hole after part of the structure of a bridge collapsed into a river in Changchun, Jilin province May 29, 2011. Two truck passengers were injured, while the cause of the accident is still under investigation, local media reported. (Photo by Reuters/China Daily)

Imagine living in the sea where it is permanently dark, cold, and food is hard to find. For many animals at depth, it may be weeks to months between meals. If you find something to eat, you have to hang on to it. This is why so many deep-sea fishes have lots of big teeth. This dragonfish, spotted off the coast of Australia, even has teeth on its tongue. They would be terrifying animals ... if they weren’t the size of a banana. (Photo by Julian Finn/Museum Victoria)

A man watches the approaching flames as the Springs fire continues to grow near Camarillo, California, on May 3, 2013. The wildfire has spread to more than 18,000 acres on day two and is 20 percent contained. (Photo by David McNew)

The Art Car Parade is the highlight of a three-day celebration of the drive to create: Art Car Weekend. But it all began with a donated 1967 Ford staton wagon and $800 worth of paint and plastic fruit. And now, 26 years later, it attracts 250+ vehicles (and other entries) from 23 states, Canada, and Mexico. Photo: An art car is seen on Allen Parkway during the 26th Annual Houston Art Car Parade on May 11 in Houston, Texas. (Photo by Scott Halleran)

The Lantern Festival in Seoul, South Korea, celebrates Buddha’s birthday. Buddha was born approximately 2,557 years ago; the exact date is unknown, but Buddha’s official birthday is celebrated on the full moon in May in South Korea, which is May 17 this year. Photo: Buddhists march on the street as they prepare for the buddha's birthday in Seoul. (Photo by Chung Sung-Jun)

Handout grab taken from YouTube of Commander Chris Hadfield who has said goodbye to life on the International Space Station by making a cover version of David Bowie's Space Oddity. Issue date: Monday May 13, 2013. (Photo by Commander Chris Hadfield/YouTube/PA Wire)