An Iraqi Shi'ite boy poses for a photograph as Iraq Shi'ite Muslims commemorate Ashura in Baghdad, October 24, 2015. Ashura, which falls on the 10th day of the Islamic month of Muharram, commemorates the death of Imam Hussein, grandson of Prophet Mohammad, who was killed in the seventh century battle of Kerbala. (Photo by Ahmed Saad/Reuters)

Drastic inequality is by no means new in New York. Jacob A. Riis was called a muckraker after he chose to spotlight the city’s poverty at the turn of the 20th century by photographing it. Here: Sweatshop in Hester Street, 1889-1890. (Photo by Jacob A. Riis/Museum of the City of New York, Gift of Roger William Riis)

A photographer takes a snapshot of the reflection of balloons as they take off from Balloon fiesta park in Corrales, N.M., near a north diversion channel reservoir Wednesday, October 7, 2015. (Photo by Roberto E. Rosales/Albuquerque Journal via AP Photo)

A Filipino transgender woman holds a huge red ribbon symbolizing fight against the HIV virus as she poses before photographers, during a World Aids Day celebration in Manila, Philippines, December 1, 2015. (Photo by Erik De Castro/Reuters)

This week's full Moon as photographed from on board the International Space Station by NASA astronaut Jeff Williams on August 19, 2016. Jeff is currently Commander of the Space Station for the Expedition 48 crew. (Photo by Jeff Williams/NASA)

Photographer Loes Heerink spent hours waiting on bridges in Hanoi to capture the street vendors who walked underneath. She recently launched a Kickstarter project to publish a book of these images. Here: “In Hanoi there are a lot of street vendors who roam the city with their bicycles trying to sell goods, from vegetables to flowers”. (Photo by Loes Heerink/The Guardian)

A vehicle leaves light trails in a long exposure photograph as it drives beneath the 500-metre Aperture Spherical Radio Telescope in Pingtang county, China. Construction on the device began in 2011 and is nearing completion. (Photo by Liu Xu/AP Photo)

A couple take photographs alongside the National Monument on Calton Hill, Edinburgh on Wednesday January 5, 2022, ahead of First Minister Nicola Sturgeon's update to the Scottish Parliament on the Covid-19 situation as the Omicron variant sweeps across the country. (Photo by Jane Barlow/PA Images via Getty Images)