Pontoons, which were previously used as a floating jetty, are seen on the cracked ground of the Atibainha dam, part of the Cantareira reservoir, during a drought in Nazare Paulista, Sao Paulo state February 12, 2015. Brazil's worst drought in 80 years has left the Cantareira system, that provides greater Sao Paulo with most of its water, with the lowest water level on record. Brazil's economy is already expected to post zero growth this year. Worse yet, since Brazil depends on hydroelectric dams for about three quarters of its electricity, power shortages are also possible due to the drought, federal officials have said. (Photo by Paulo Whitaker/Reuters)

A United States Air Force (USAF) F-15 fighter jet travels at low altitude through the “Mach Loop” series of valleys near Dolgellau, north Wales on June 26, 2018. The Mach Loop valleys, situated between Dolgellau and Machynlleth, are regularly used by the military for operational low flying training which can take place as low as 76 metres from the nearest terrain. The USAF regularly use the loop to practice low-altitude flight, which confuses radar systems. (Photo by Oli Scarff/AFP Photo)

“The nuclear football (also known as the atomic football, the president's emergency satchel, the button, the black box, or just the football) is a briefcase, the contents of which are to be used by the President of the United States of America to authorize a nuclear attack while away from fixed command centers, such as the White House Situation Room. It functions as a mobile hub in the strategic defense system of the United States. It is a metallic Zero Halliburton briefcase carried in a black leather “jacket”. The package weighs around 45 pounds (20 kilograms). A small antenna protrudes from the bag near the handle”. – Wikipedia

Photo: A U.S. Military officer carries the “football”, which carries nuclear launch codes, on South Lawn after returning with U.S. President George W. Bush to the White House January 7, 2002 in Washington, DC. (Photo by Mark Wilson/Getty Images)

“I'm Josh Fancher, a 21 year old with an avid interest in photography, including macro, nature and wildlife, night photography, landscapes, cityscapes and architectural photography. Inspired by the beautiful and amazing water drop photography of Martin Waugh, I started doing water drop collisions in December of 2007. I use a 105mm Micro Nikkor lens for water drops, along with a pair of Nikon SB 600 flashes. I recently got a StopShot system (Nov 2009), which makes timing a lot easier. Before then, timing was manual, with an eye dropper, eye-hand coordination, and a lot of patience” – Josh Fancher. (Photo by Josh Fancher)

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)

The new EVR system which allows the recording of television programmes which can then be watched at the owner's discretion. The new Teleplayer has been produced in partnership with Rank Bush Murphy Ltd and EVR and has enormous potential. 21st September 1970. (Photo by Central Press/Getty Images)

A protester reacts as police use water cannon during a demonstration to demand changes in the Chilean education system in Santiago, Chile June 25, 2015. (Photo by Ueslei Marcelino/Reuters)