Female panda Tian Tian makes her first appearance in front of the media since arriving from China on December 12, 2011 in Edinburgh, Scotland. (Photo by Jeff J. Mitchell/Getty Images)

People work with cocoa beans in Enchi June 17, 2014. Picture taken June 17, 2014. Ghana emerged as a success story during the 2000s, when war, political instability and a disastrous liberalization brought Ivory Coast's cocoa sector to its knees. Ghana's output more than tripled from 340,000 tons in the 2001/02 season to a record 1,025,000 tons a decade later. Strict controls cemented its reputation as a producer of top quality beans, establishing a brand that fetches a premium. (Photo by Thierry Gouegnon/Reuters)

The Hubble Space Telescope is shown following its release from the space shuttle Discovery Wednesday, February 19, 1997. The Hubble Space Telescope, one of NASA'S crowning glories, marks its 25th anniversary on Friday, April 24, 2015. With more than 1 million observations, including those of the farthest and oldest galaxies ever beholden by humanity, no man-made satellite has touched as many minds or hearts as Hubble. (Photo by AP Photo/NASA)

An orphaned giraffe nuzzling a wildlife keeper at Sarara camp in Kenya, one of 70 pictures being sold by Prints for Nature (printsfornature.com) to raise money for work by the Conservation International charity. This giraffe was rehabilitated and returned to the wild, as a number of others have done before him. Right now, giraffe are undergoing what has been referred to as a silent extinction. Current estimates are that giraffe populations across Africa have dropped 40 percent in three decades, plummeting from approximately 155,000 in the late 1980s to under 100,000 today. (Photo by Ami Vitale/National Geographic)

Competitors climb in front of the Matterhorn mountain at the start of the 21st Glacier Patrol race in Stafel outside the ski resort of Zermatt, Switzerland, 18 April 2018. The Glacier Patrol (Patrouille des Glaciers in French), organized by the Swiss Army, takes place from April 17 to 21. Highly-experienced hiker-skiers trek for over 53km (3994m ascent and 4090m descent) along the Haute Route along the Swiss-Italian border from Zermatt to Verbier. (Photo by Valentin Flauraud/EPA/EFE)

Woman dons a mask a she prepares to dance in the streets during the feast of La Diablada, in Pillaro, Ecuador, Friday, January 4, 2019. The town of Pillaro kicks off the feast of the La Diablada with neighborhoods competing to bring as many people dressed as different characters. (Photo by Dolores Ochoa/AP Photo)

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)

In this July 29, 2016 photo, cowgirl Dariadna Corujo winds up to lasso a calf during an improvised rodeo event at a farm in Sancti Spiritus, central Cuba. At the tender age of 6, Dariadna is already an expert barrel racer and calf roper. In the flat grasslands of Sancti Spiritus, a group of neighboring cattle ranchers founded a non-governmental organization called Future Ranchers more than a decade ago to revive Cuba’s rodeo culture, which dates back centuries to Spanish colonial times. (Photo by Ramon Espinosa/AP Photo)