A man wearing a face mask walks past a picture of a Russian tank in central Moscow on June 18, 2020. Russia's President Putin on June 24 will preside over a massive military parade to mark Soviet victory in World War II, which was postponed due to the coronavirus pandemic. (Photo by Yuri Kadobnov/AFP Photo)

This handout photo taken on August 31, 2023 and provided by the South Korean Defence Ministry shows South Korean soldiers participating in an air assault drill at a training field in Jangseong, as part of the annual Ulchi Freedom Shield joint military drills between South Korea and the United States. (Photo by Handout/South Korean Defence Ministry/AFP Photo)

US M142 High Mobility Artillery Rocket System (HIMARS) is launched as journalists film during a military exercise in Capas, Tarlac province, Philippines, 13 October 2022. The Philippines hosted simultaneous combat drills with the United States, South Korea, and Japan to improve interoperability in times of conflict. (Photo by Francis R. Malasig/EPA/EFE)

Women take a picture atop a destroyed Russian tank during an exhibition displaying destroyed Russian military vehicles, amid Russia's invasion, in central Kyiv, Ukraine on March 21, 2023. (Photo by Gleb Garanich/Reuters)

The lightest material ever made has been produced by a team of scientists in China, a Chinese university announced.

In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)