A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. Image taken by NASA's Hubble Space Telescope. Released September 24, 2015. (Photo by Reuters/NASA/ESA/Hubble Heritage Team)

A woman walks on the stairs decorated with an image of two hands shaking to form the shape of the Korean Peninsula to support the upcoming inter- Korean summit, in downtown Seoul on September 17, 2018. South Korean President Moon Jae- in will fly to the North Korean capital on September 18, for his third summit with the North' s leader Kim Jong Un as a rapid diplomatic thaw takes hold on the peninsula despite stalled progress in denuclearisation talks between Pyongyang and Washington. (Photo by Jung Yeon-je/AFP Photo)

A boy holds a machine gun at a military hardware exhibition during a swear-in ceremony for new recruits of the Russian military-patriotic club “Yunarmia” (Young army) in the Black Sea port of Sevastopol, Crimea, October 27, 2018. (Photo by Pavel Rebrov/Reuters)

Female labourers wearing helmets take a break from laying underground electricity cables in Ahmedabad, India, March 7, 2016. (Photo by Amit Dave/Reuters)

This photo taken on July 19, 2020 shows a person taking photos while water is released from the Three Gorges Dam, a gigantic hydropower project on the Yangtze river, to relieve flood pressure in Yichang, central China's Hubei province. Rising waters across central and eastern China have left over 140 people dead or missing, and floods have affected almost 24 million since the start of July, according to the ministry of emergency management. (Photo by AFP Photo/China Stringer Network)

A taxi driver waits for passengers inside his taxi parked on the side of a deserted road during the first day of the two-day state-imposed lockdown as a preventive measure against the surge in COVID-19 coronavirus cases in Kolkata on August 20, 2020. (Photo by Dibyangshu Sarkar/AFP Photo)

Arcelia Aguilar, a resident of “Hogar Jardin De Los Abuelitos”, receives a hug from her niece Maria Aguilar through “El muro de los Abrazos” (The Wall of Hugs) which is a wall made from plastic sheets to protect against the coronavirus, in San Salvador, El Salvador on September 1, 2020. (Photo by Jose Cabezas/Reuters)

A face mask discarded in a forest in the Taunus region near Frankfurt, Germany, Sunday, October 18, 2020. (Photo by Michael Probst/AP Photo)