Three one-month-old lioness cubs are held by a keeper as they take their first outing on February 21, 2010 at the Ramat Gan Safari Park near Tel Aviv, Israel. The still unnamed cubs are the first triplet females to be born at the safari park and officials say their birth will ensure the continuity of the park's pride of lions. (Photo by David Silverman/Getty Images)

Men are sent down into the sludge to clear the sewers in the Bangladeshi capital Dhaka on May 23, 2018. The people who do the work aren’t even given any protective clothing or goggles and have to dig out the clogged-up muck with a stick or their bare hands. (Photo by Rehman Asad/Barcroft Media)

It’s time to start watching for Comet PANSTARRS, one of two comets to get excited about in 2013. Photo: This image provided by NASA shoaws the comet PANSTARRS as seen from Mount Dale, Western Australia on March 5, 2013. According to NASA on March 10, it will make its closest approach to the sun about 28 million miles (45 million kilometers) away. As it continues its nightly trek across the sky, the comet may get lost in the sun's glare but should return and be visible to the naked eye by March 12. (Photo by AP Photo/NASA)

A photographer tested the concentration of several pairs of dogs as he captured their reactions to treat time in a series of shots. Christian Vieler, 47, of Waltrop, Germany, has been a professional dog photographer since 2016. He came up with the idea of snapping two dogs catching treats simultaneously. Here: Basset Hounds. (Photo by Vieler Photography/Caters News Agency)

Caporal dancers perform during the carnival celebrations in Oruro, Bolivia, Saturday February 14, 2015. The Carnival of Oruro which is a religious festival dating back more than 2000 years in an ongoing pagan-catholic blend of religious practice in the region, and is one of UNESCO's Masterpieces of the Oral and Intangible Heritage of Humanity. (Photo by Juan Karita/AP Photo)

“On 24 July 2010, a stampede at the 2010 Love Parade electronic dance music festival in Duisburg, North Rhine-Westphalia, Germany, caused the death of 21 people. At least 510 more were injured”. – Wikipedia

Photo: Wall art and candles are pictured in the tunnel of the 2010 Loveparade disaster near to where many of the deaths occurred on the first anniversary of the tragedy on July 24, 2011 in Duisburg, Germany. (Photo by Thomas Starke/Getty Images)

In this composite image (top) flooding is seen in the Toowoomba central business district on January 10, 2011 and (bottom) the same location as seen on January 5, 2012 in Toowoomba, Australia. January 10 marks the one year anniversary of the inland tsunami that devestated southern Queensland's Lockyer valley killing 23 people. (Photos by Dan Proud (top) and Lisa Maree Williams (bottom) /Getty Images)