A farmer tends to his field as Mount Sinabung releases pyroclastic flows in Tiga Pancur, North Sumatra, Indonesia, Saturday, June 13, 2015. The volcano, which was put on it highest alert level last week, has sporadically erupted since 2010 after being dormant for 400 years. (AP Photo/Binsar Bakkara)

In advance of Fleet Week performances, the U.S. Navy Blue Angels and Team Oracle aerobatics pilot Sean D. Tucker fly over the San Francisco Bay during a photo flight on Thursday, October 5, 2017. (Photo by Noah Berger/AP Photo)

Thousands of heavy-duty trucks loaded with coal are lined up for up to 130 kilometres from the Mongolia-China border on a sole road in the Gobi desert, Mongolia, October 29, 2017. The journey can take more than a week. (Photo by Bazarsukh Rentsendorj/Reuters)

This week's full Moon as photographed from on board the International Space Station by NASA astronaut Jeff Williams on August 19, 2016. Jeff is currently Commander of the Space Station for the Expedition 48 crew. (Photo by Jeff Williams/NASA)

A boy removes rain water from his hut after a heavy downpour in Karachi, Pakistan, 28 August 2016. Heavy monsoon rains across the country has claimed dozens of lives in last few weeks as Pakistan Meteorological Departmen office predict more rains in coming days. (Photo by Shahzaib Akber/EPA)

A participant takes part in the annual Jack In The Green parade involving hundreds of costumed revellers joining a four hour procession culminating in the traditional “slaying” of a Jack character to “unleash the spirit of summer” on the May Day week end, in Hastings, southern Britain, May 2, 2016. (Photo by Toby Melville/Reuters)

A videographer uses a drone as he takes a video of a model presenting a lingerie creation at the rehearsal for Eve's Temptation collection during China Fashion Week in Beijing, October 26, 2014. (Photo by Kim Kyung-Hoon/Reuters)