International Space Station crew members Serena Aunon-Chancellor of the US, Alexander Gerst of Germany and Sergey Prokopyev of Russia mark Halloween in this photo released on November 1, 2018.(Photo: VCG)

China's home-grown global satellite navigation system came a step closer to completion with the launch of another BeiDou-3 satellite on November 1, 2018 from the Xichang Satellite Launch Center, in the southwestern Sichuan Province. (Photo: Liang Keyan/People's Daily).

A gallery assistant poses with a copy of the book 'A Brief History of Time' by theoretical physicist Stephen Hawking signed with a thumbprint with an estimate price of £2,000-£3,000 during a photo call for the sale of personal items from Hawking's estate, at Christie's auction house in London on October 30, 2018. (Photo: VCG)

The wreckage of a Chongqing bus that plunged into the Yangtze River is lifted out of the water in Wanzhou, Chongqing on October 31, 2018. (Photo: China Daily)

Trucks carrying mostly Honduran migrants in a caravan heading to the US drive from Santiago Niltepec to Juchitan, near the town of La Blanca in Oaxaca State, Mexico, on October 30, 2018. (Photos: VCG)

A Palestinian protester hurls stones with a slingshot at a demonstration on the beach near the maritime border with Israel, in Beit Lahia in the northern Gaza Strip, on October 29, 2018.

A man rummages through garbage between two yachts after a storm hit the harbor and destroyed part of the dam on October 30, 2018 in Rapallo, Italy.

A man uses a torch to walk through a park during a cold foggy night in Athboy, Ireland, on October 31, 2018.

Performers participate in the Samhuinn Fire Festival - a celebration of the Celtic New Year - on Calton Hill in Edinburgh, Scotland, October 31, 2018.

Dozens of red-faced snow monkeys huddle together to keep warm as they battle freezing temperatures. The photograph was taken in Shodoshima, an island in Japan's Seto Inland Sea, where temperatures can drop to below freezing, according to a report on October 31, 2018. (Compiled by Yao Xia)