An Indian Hindu widow smeared with colors sits and watches others playing during Holi celebrations at the Gopinath temple, 180 kilometres (112 miles) south-east of New Delhi, India Monday, March 21, 2016. A few years ago this joyful celebration was forbidden for Hindu widows. Like hundreds of thousands of observant Hindu women they would have been expected to live out their days in quiet worship, dressed only in white, their very presence being considered inauspicious for all religious festivities. (Photo by Manish Swarup/AP Photo)

Two women wearing bejewelled bras kiss during the annual Sydney Gay and Lesbian Mardi Gras festival in Sydney, Australia March 4, 2017. (Photo by Jason Reed/Reuters)

Iraqis who have fled fighting between security forces and al-Qaida inspired militants in their hometown of Tal Afar arrive in a car at Germawa camp for displaced Iraqis, in a hot dusty plain in the largely-autonomous Kurdish area of Dahuk, 260 miles (430 kilometers) northwest of Baghdad Tuesday, June 17, 2014. (Photo by AP Photo)

Rickshaw drivers wade through a flooded road after heavy rains swept through Guwahati, in the northeastern Indian state of Assam, on June 26, 2014. Seven people have been killed there in flash floods, landslides and heavy rainfall, local media reported Friday. (Photo by Utpal Baruah/Reuters)

Participants take pictures of themselves as others run past the Tiananmen gate during the Beijing Marathon in Beijing, China, September 17, 2016. (Photo by Damir Sagolj/Reuters)

Spacewalker Mark Vande Hei took his own photograph during the first spacewalk of 2018, on January 23, 2018. These sky-high pictures are better known as “space-selfies”. (Photo by Mark Vande Hei/NASA)

A U.S. Marine kneels beside a Multi-Utility Tactical Transport ( MUTT) during a patrol as part of Rim of the Pacific (RIMPAC) 2016 an exercise held at Camp Pendleton, California United States, July 13, 2016. (Photo by Mike Blake/Reuters)

The Jet Propulsion Lab team's RoboSimian robot turns on a valve at a simulated disaster-response course during day one of the Defense Advanced Research Projects Agency (DARPA) Robotics Challenge finals in Pomona, California, June 5, 2015. (Photo by David McNew/Reuters)