Girls Aloud: Nicola Roberts, Kimberley Walsh, Sarah Harding and Cheryl Cole at Kimberley Walsh's birthday party hosted by Damian Darkko at Mint Nightclub in London, Britain on November 25, 2006. The Girls Aloud star Sarah Harding has died at the age of 39, her mother has said in a post on Instagram. Issue date: Sunday September 5, 2021. (Photo by Rex Features/Shutterstock)

A Geminid meteor streaks diagonally across the sky against a field of star trails behind one of the peaks of the Seven Sisters rock formation in this long exposure early December 14, 2007 in the Valley of Fire State Park in Nevada. The meteor display, known as the Geminid meteor shower because it appears to radiate from near the star Castor in the constellation Gemini, is thought to be the result of debris cast off from an asteroid-like object called 3200 Phaethon. The shower is visible every December. (Photo by Ethan Miller/Getty Images)

“The Dream Chaser is a planned crewed suborbital and orbital vertical-takeoff, horizontal-landing (VTHL) lifting-body spaceplane being developed by SpaceDev, a wholly owned subsidiary of Sierra Nevada Corporation (SNC). The Dream Chaser design is planned to carry seven people to and from low earth orbit. The vehicle would launch vertically on an Atlas V and land horizontally on conventional runways”. – Wikipedia

Photo: NASA Deputy Administrator Lori Garver talks during a press conference with Sierra Nevada's Dream Chaser spacecraft in the background at the University of Colorado at Boulder on February 5, 2011 in Boulder, Colorado. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. (Photo by Bill Ingalls/NASA via Getty 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.

An incredible view of daytime lightning on Saturn during one of the biggest storms the ringed planet has ever seen has been captured by a NASA spacecraft.

Photo: The huge storm which generated the lightning strike on Saturn can be seen in the top right of this image. (Photo by NASA)

Thousands of species of amphibians are endangered and hundreds have already disappeared, but in recent years, a team of scientists and conservationists have re-discovered some of these “lost” species and uncovered previously unknown varieties. Here: Miniature glass frog. (Photo by Robin Moore)

A view of the spectacular colour of clouds at sunset on January 17, 2005 in Beijing, China. (Photo by China Photos/Getty Images)