A high temperature alerts were issued as a record-setting summer heat wave continued to bake most parts of south China. (Reuters)

In this September 14, 2017 photo, young women pose for a photo inside their squatter building that used to house the Brazilian Institute of Geography and Statistics (IBGE) in the Mangueira slum of Rio de Janeiro, Brazil. Many lower-middle class Brazilians who gained ground during the boom years have since slid back closer to the poverty line. (Photo by Felipe Dana/AP Photo)

A migrant labourer brushes his teeth in front of a scrapped helicopter model in Mumbai, India, April 13, 2016. (Photo by Danish Siddiqui/Reuters)

The competition, which is run by the Royal Observatory Greenwich in association with BBC Sky at Night Magazine, is now in its sixth year and has received over 2,500 entries. Photo: Centre of the Heart Nebula by Ivan Eder (Hungary). Situated 7500 light years away in the “W”-shaped constellation of Cassiopeia, the Heart Nebula is a vast region of glowing gas, energized by a cluster of young stars at its centre. The image depicts the central region, where dust clouds are being eroded and moulded into rugged shapes by the searing cosmic radiation. (Photo by Ivan Eder)

A boat is stranded on Poyang Lake in Lushan City, China during low-water season on November 3, 2016. (Photo by Xinhua/Barcroft Images)

The current world Champions in the Men's and Women's RS:X, Piotr Myszka of Poland and Blanca Manchon of Spain arrive at Bathers Beach carrying the ISAF World Championships Flag to be raised to officially open the 2011 ISAF Sailing World Championships on December 2, 2011 in Perth, Australia. (Photo by Mark Dadswell/Getty Images)

Steve Shirts, aka “Strike Pony”, left, gets a hug from Amber Snyder, aka “Ditsy Dots” in Baltimore, MD on July 8, 2016. Both are from Suburban Chicago. BronyCon is the world's largest My Pretty Pony convention. Featuring cosplay and fan events, the annual convention was held at the Baltimore Convention Center. (Photo by Andre Chung/The Washington Post)

Members of the traditional Los Historiantes dance group perform during a welcoming ceremony for Catholic devotees known as "Cumpas", in the town of Cuishnahuat, El Salvador November 26, 2015. The Catholic people of the El Balsamo mountain range meet in the village of Cuishnahuat in November to celebrate the 'friendship' between their respective patron saints in a ceremony that has been carried out for more than 300 years, according to the government. (Photo by Jose Cabezas/Reuters)