Battle-weary American troops withdraw from Yong San in Korea. (Photo by Keystone/Getty Images). 1950

The HMAS Adelaide is scuttled off the coast of Avoca Beach on April 13, 2011 in Gosford, Australia. After the scuttling was succesfully protested in 2010, today the HMAS Adelaide was finally scuttled off the NSW Central Coast to create an artifical reef, the first of its kind in this state. (Photo by Brendon Thorne/Getty Images)

Russian marines attached to the anti- submarine ship Admiral Tributs show their skills during a demonstration at a park in Manila on January 5, 2017, as part of their five- day port- of- call activities in the country' s capital. (Photo by Ted Aljibe/AFP Photo)

A B-52 bomber is watched by a group of curious onlookers as it lands at RAF Fairford, February 21, 1999. The B52s arrived from the U.S.A. as part of NATO's preparations for air attacks on Yugoslavia as tensions in the Kosovo crisis increased. (Photo by Dylan Martinez/Reuters)

The tusk of a woolly mammoth that lived some 18,000 years ago, from which researchers sequenced the extinct mammal's entire genome, is seen in northeastern Siberia in this photo from 2015. (Photo by Love Dalen/Handout via Reuters)

An Iranian girl walks past a mural with Iran's national flag in a street in Tehran, Iran, 03 December 2020. Iranian president Rouhani said that his government does not agree with the parliament's draft bill to quit the nuclear deal, to reduce nuclear commitment and to increase nuclear activities. The development comes after the assassination of Iranian nuclear scientist Mohsen Fakhrizadeh earlier this week. (Photo by Abedin Taherkenareh/EPA/EFE/Rex Features/Shutterstock)

An Egyptian security guard screams at people as medics bring in a stretcher to carry the wounded after the attack which killed President Anwar Sadat, October 6, 1981, as he watched a military parade. (Photo by AP Photo)

A view of the Lakhta Center multifunctional complex under construction in St Petersburg' s Primorsky District and a cable stayed bridge of the Western High- Speed Diameter toll motorway in St Petersburg, Russia on March 5, 2018. (Photo by EPA/EFE/Rex Features/Shutterstock)