A boy wearing a World War II guerrilla cap with the five-point star attends the Victory Day ceremony in Belgrade, Serbia, Monday, May 9, 2022. People are marking the 77th anniversary of the victory over Nazi Germany in WWII. (Photo by Darko Vojinovic/AP Photo)

Participants of the Cologne Pride rally pose in front of the Cathedral in Cologne, Germany, Sunday, July 3, 2022. This year's Christopher Street Day (CSD) Gay Parade with thousands of demonstrators for LGBTQ rights is the first after the coronavirus pandemic to be followed by hundreds of thousands of spectators in the streets of Cologne. (Photo by Martin Meissner/AP Photo)

A handout photo provided by the Police department in Lippe on 01 June 2015 of a British “Challenger 2” tank after it rolled over a car's front in Lippe, Germany, 01 June 2015. Police reported that a 18-year old female driving beginner from Detmold apparently overlooked a convoy of tanks when she turned left onto the Panzeringstrasse (lit. Tank Ring Road). (Photo by EPA/Polizei Lippe)

Women sell bananas in the street, after traders in markets were prohibited from selling any non-food items in an attempt to halt the spread of the new coronavirus, in Kampala, Uganda Thursday, March 26, 2020. (Photo by Ronald Kabuubi/AP Photo)

A boy attends Eid al-Adha prayers on the street outside Abu Hanifa mosque in Baghdad Adhamiya district, during the outbreak of the coronavirus disease (COVID-19), in Iraq, July 31, 2020. (Photo by Thaier Al-Sudani/Reuters)

A wrestling camel adorned with colourful ornaments takes part in the Camel Beauty Contest ahead of the annual 40th Efes Selcuk Camel Wrestling Festival, in the Aegean town of Selcuk, near Izmir, Turkey on January 15, 2022. (Photo by Murad Sezer/Reuters)

Ana Mendez Casteñeda smokes marijuana during “Fumaton 420” outside the national Senate in Mexico City, Tuesday, April 20, 2021. The demonstrators are calling for the legalization of marijuana. (Photo by Marco Ugarte/AP Photo)

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