On Earth Day this year, NASA asked people all around the world a question: “Where are you on Earth Right Now?” To answer this question people were asked to post their selfie on social media. The goal was to use each picture as a pixel in the creation of a “Global Selfie” – a mosaic image that would look like Earth appeared from the space. The 3.2 gigapixel “Global Selfie”, was made the with 36,422 individual images.

Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.

Relatives clean the body of Paul Sampe Lumba who has been dead for seven yeas during the Ma'nene ritual at Panggala Village on August 26, 2016 in Toraja, Indonesia. The Ma'nene ritual in performed during a ceremony every three years, where the dead are exhumed for a change of clothes, among the people of Toraja as an expression of the love of the surviving family. (Photo by Sijori Images/Barcroft Images)

Geology Professor Fetullah Arik takes measurements next to a large sinkhole on June 03, 2021, in Karapinar, Turkey. In Turkey’s Konya province, the heart of the country's agriculture sector, extreme drought conditions over the past two years are taking a heavy toll on farmers and the land. (Photo by Chris McGrath/Getty Images)

A protester uses molotov cocktails against riot police during May Day protests on May 1, 2010 in Athens, Greece. (Photo by Milos Bicanski /Getty Images)

For more than 2,000 years, women from the Baiga tribe in the highland district of Dindori, in central India’s Madhya Pradesh state, have been tattooed. Sumintra, 25, from Bona village, has the markings across her forehead, legs and arms. The women who work as tattoo artists are knowledgable about the different types of designs and pigments preferred by various tribes, and their meanings are passed to them by their mothers. The tattooing ‘season’ begins with the approach of winter. (Photo by Ronny Sen/WaterAid/The Guardian)

A competition, now in its 43rd year, dedicated to showcasing the beautiful and bizarre as seen under a light microscope attracted over 2,000 entries from 88 countries. Here: Honorable Mention by Emre Can Alagöz, Istanbul, Turkey: The eyes of a jumping spider, magnified 6x. (Photo by Emre Can Alagöz/2017 Nikon Small World Photomicrography Competition)

Penguins majestically march on sand before heading out for a morning swim. Wildlife photographer Wim van den Heever, 45, visited the Falkland Islands this year to shoot pictures and scout the area for future tours. Wim’s breathtaking images show a small group of king penguins before they head out to sea at sunrise. Here: King Penguins marching during sunrise, Falkland Islands. (Photo by Wim van den Heever/Caters News)