In this July 8, 2019, photo, a monkey pulls on the clothes of Saraswati Dangol as she arrives to feed monkeys in the forest near Pashupatinath temple in Kathmandu, Nepal. For the past four years, Dangol has been bringing the bread every day to feed the monkeys. As soon as they see her with her white sack, they gather around her, some patiently waiting for their turn while others less patiently snatching the bread from her hands. Many of Dangol's regulars are elderly, or are mother or baby monkeys who are unable to fight for their share of food in the wild. (Photo by Niranjan Shrestha/AP Photo)

NASA says it could be another 20 years before humans touch down on Mars, but in a sense, the Mars Society has been exploring the red planet for more than a decade – in Utah. Photo: Csilla Orgel, a geologist of Crew 125 EuroMoonMars B mission, makes her way back to the Mars Desert Research Station (MDRS) in the Utah desert March 3, 2013. The MDRS aims to investigate the feasibility of a human exploration of Mars and uses the Utah desert's Mars-like terrain to simulate working conditions on the red planet. Scientists, students and enthusiasts work together developing field tactics and studying the terrain. All outdoor exploration is done wearing simulated spacesuits and carrying air supply packs and crews live together in a small communication base with limited amounts of electricity, food, oxygen and water. Everything needed to survive must be produced, fixed and replaced on site. (Photo by Jim Urquhart/Reuters)

A man with a cap on his face sleeps on a floor at the Mahabat Khan Mosque in Peshawar, Pakistan on March 4, 2019. (Photo by Fayaz Aziz/Reuters)

Huge pack of starlings in the sky of the Negev, Israel, on January 21, 2013. Birds are turned in evening twilight before settling to sleep. (Photo by Eliyahu Hershkovitz)

Workers sleep on a railway track under repair in New Delhi, India, June 15, 2018. (Photo by Saumya Khandelwal/Reuters)

A man sleeps at Beirut's Corniche, a seaside promenade, in Lebanon May 2, 2016. (Photo by Alia Haju/Reuters)

Sleeping Anthidium. Female Anthidium punctatum; Size: 7 mm. (Photo by John Hallmén)