The possible surface of TRAPPIST-1f, one of seven newly discovered planets in the TRAPPIST-1 system that scientists using the Spitzer Space Telescope and ground based telescopes have discovered. (Photo by Reuters/NASA/JPL-Caltech)

Nyibol Lual, 13 years old, helps her family to prepare the land for cultivation on May 31, 2017, in Panthau, Northern Bahr al Ghazal, South Sudan. The family has a small land where they cultivate sorghum. An estimated 63 per cent of the population in Northern Bahr al Ghazal is experiencing severe food insecurity, according to the latest Integrated Food Security Phase Classification (IPC) report. The situation is particularly bad in Aweil West and Aweil South counties, where the exhaustion of household food stocks and growing dependence on financially inaccessible markets have left the population facing Emergency levels of food insecurity. (Photo by Albert Gonzalez Farran/AFP Photo)

A woman, wearing a traditional Sevillana dress, performs as she asks for alms in downtown Malaga, Spain, April 28, 2016. (Photo by Jon Nazca/Reuters)

A Monster Jam truck performs a back flip during the first-ever monster truck event in Beijing's iconic “Bird's Nest” National Stadium on Saturday, July 29, 2017. (Photo by Ng Han Guan/AP Photo)

The sun begins to set over this rusty beachside mansion that has been left abandoned for more than 25 years in Thailand, June 2017. A deserted beachside mansion in southern Thailand has retained its beauty – despite no one living there for more than 25 years. In June this year abandoned photographer, Dax Ward, ventured to the Prachuap Khiri-Khan Province to capture the haunting attraction on camera. (Photo by Dax Ward/Barcroft Images)

Young girls perform in front of the monument to Soviet state founder Vladimir Lenin during the City Day celebrations in Yekaterinburg, Russia on August 19, 2017. (Photo by Maxim Shemetov/Reuters)

16-year-old panda, Ye Ye, rests in an enclosure at the Wolong Nature Reserve, a conservation center that trains pandas for release into the wild. This image was published in the August 2016 National Geographic magazine as part of the “Pandas Gone Wild” story. (Photo by Ami Vitale/National Geographic Creative)

A drunk student is sick on the street watched by a police officer following a night of heavy drinking during freshers week in United Kingdom on November 28, 2007. (Photo by Matthew Horwood/Alamy Stock Photo)