A United States Air Force (USAF) F-15 fighter jet travels at low altitude through the “Mach Loop” series of valleys near Dolgellau, north Wales on June 26, 2018. The Mach Loop valleys, situated between Dolgellau and Machynlleth, are regularly used by the military for operational low flying training which can take place as low as 76 metres from the nearest terrain. The USAF regularly use the loop to practice low-altitude flight, which confuses radar systems. (Photo by Oli Scarff/AFP Photo)

Firefighters watch as an air tanker drops retardant while battling the Ferguson fire in the Stanislaus National Forest, near Yosemite National Park, California on July 21, 2018. A fire that claimed the life of one firefighter and injured two others near California's Yosemite national park has almost doubled in size in three days, authorities said Friday. (Photo by Noah Berger/AFP Photo)

Katie Rose Hobbs and Kirsten Elizabeth Pobjoy of British Aerosuperbatics Wingwalking Team perform ballet in the air during Huangguoshu Waterfalls Flight Conference on August 3, 2018 in Anshun, Guizhou Province of China. Huangguoshu Waterfalls Flight Conference including 18 aircraft from seven aerobatic teams from all over the world kicked off on Friday. (Photo by VCG via Getty Images)

A DC-10 air tanker delivers flame retardant to the Blue Cut fire in Wrightwood, Calif., Wednesday, August 17, 2016. A wildfire with a ferocity never seen before by veteran California firefighters raced up and down canyon hillsides, instantly engulfing homes and forcing thousands of people to flee, some running for their lives just ahead of the flames. (Photo by Alex Gallardo/AP Photo)

The deserts of Argentina take on a starring role in this photographer’s breathtaking Milky Way shots. Amateur snapper Gonzalo Javier Santile, 46, spent the last two years capturing these rare shots of the galaxy as it arced over deserts in Salta Cafayate, Cordoba Valle de Punilla, Provincia de Buenos Aires and the Rio Negro province. In his pictures, the Milky Way can be admired as it towers over canyons, cacti, bushes, and even small brooks and lakes. (Photo by Gonzalo Javier Santile/Caters News Agency)

A U.S. Army soldier with the 10th Special Forces Group and his military working dog jump off the ramp of a CH-47 Chinook helicopter from the 160th Special Operations Aviation Regiment during water training over the Gulf of Mexico as part of exercise Emerald Warrior 2011 on March 1, 2011. (Photo by Tech. Sgt. Manuel J. Martinez/U.S. Air Force)

Kenny Wallace, driver of the #09 Family Farmers Toyota, spins into Justin Allgaier, driver of the #31 Brandt Chevrolet, who is lifted into the air by Reed Sorenson, driver of the #52 Means Racing Chevrolet, as Michael Annett, driver of the #43 Pilot Flying J. Ford, tries to avoid the wreckage during the NASCAR Nationwide Series DRIVE4COPD 300 at Daytona International Speedway on February 25, 2012 in Daytona Beach, Florida. (Photo by John Harrelson/Getty Images for NASCAR)