Policemen guard Poland's Supreme Court as a protester lies on the pavement in Warsaw, Poland, on Thursday, April 22, 2021. A disputed disciplinary body within Poland's Supreme Court is examining a motion that could result in the arrest of a judge who has become a symbol of the fight for an independent judiciary. (Photo by Czarek Sokolowski/AP Photo)

Bullet the bulldog skateboards in a seafront area in the city of Vladivostok, on Russia's Pacific coast on August 9, 2021. The 6-year-old dog learnt how to skateboard two years ago thanks to his owner, Sergei Shukshuyev. (Photo by Yuri Smityuk/TASS)

Underwater photographer of the year 2020 and wide angle category winner: Frozen Mobile Home by Greg Lecoeur (France) in the Antarctic peninsula, Antarctica. Crabeater seals swim around an iceberg. These massive and mysterious habitats are dynamic kingdoms that support marine life. As they swing and rotate slowly through polar currents, icebergs fertilise the oceans by carrying nutrients from land that spark blooms of phytoplankton, fundamental to the carbon cycle. (Photo by Greg Lecoeur/Underwater Photographer of the Year 2020)

A woman walks past murals adorning the walls of Garibaldi subway station, in Milan, Friday, February 28, 2020. Due to the COVID-19 virus outbreak in northern Italy, the bustling metropolis of Milan has resembled more of a ghost town lately, as workers stayed home and tourism has dwindled there, and other parts of Italy. (Photo by Luca Bruno/AP Photo)

An Oriental Garden Lizard sits on a tree in Gauhati, India, Tuesday, April 16, 2019. During the breeding season, the male lizard's head and throat turn a bright color. (Photo by Anupam Nath/AP Photo)

British underwater photographer of the year 2021, British waters wide angle category winner and My Backyard category winner. While You Sleep by Mark Kirkland (United Kingdom), common frog taken in Malls Mire, Glasgow, Scotland. (Photo by Mark Kirkland/Underwater Photographer of the Year 2021)

Members of the Women's veteran movement take part in the March of Defenders of Ukraine as part of Ukraine's Independence Day celebrations, in Kyiv, Ukraine on August 24, 2020. (Photo by Gleb Garanich/Reuters)

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