Mount Sinabung spews pyroclastic smoke, seen from Tiga Pancur village on October 13, 2014 in Berastagi, Karo district, North Sumatra, Indonesia. Mount Sinabung, which has lain dormant for over 400 years, has been intermittently erupting since September 15 last year, killing 15 people and forcing hundreds to flee their homes. According to The National Disaster Mitigation Agency, more than 3,000 residents are still displaced. (Photo by Ulet Ifansasti/Getty Images)

M42 Subtle V1 cropped. One of the most well-known astronomical objects in our universe is the Orion Nebula and this image depicts the wider region of the Orion Molecular Cloud Complex that is its home. This complex also includes another popular target for astrophotographers, the Horsehead Nebula, as well as Barnard’s Loop and the Running Man Nebula, which can be seen to the left of this photograph. (Photo by Patrick Gilliland)

Unnati, 6 years old, at home with his sister Ishika, 4 years old, in the Mahamai Ka Bagh neighborhood. Unnati was born to parents contaminated by a carcinogenic and mutagenic water supply. This year marks the 31st anniversary of the 1984 Union Carbide gas tragedy that killed thousands of citizens of Bhopal within 72 hours and has gone on to claim thousands more as a result of the polluted environment. (Photo by Giles Clarke/Getty Images)

A man carries a dog and wades through a flooded street in Chennai, in the southern Indian state of Tamil Nadu, Wednesday, December 2, 2015. Weeks of torrential rains have forced the airport in the state capital Chennai to close and have cut off several roads and highways, leaving tens of thousands of people stranded in their homes, government officials said Wednesday. (Photo by AP Photo)

In this picture taken on Saturday, January 31, 2015, Zohreh Etezadossaltaneh, center, talks on her mobile phone, held with her foot, during a meeting at her friend's home in Tehran, Iran. Now 52 years old, the retired Iranian teacher who was born without arms has dedicated herself to helping others with similar disabilities live full and satisfying lives. (Photo by Ebrahim Noroozi/AP Photo)

Three-years-old dog Hope uses a wheelchair to run next to its owner Regine Grosinger in Vienna September 3, 2014. Hope was found with cut-off back legs in the countryside and brought to an animal asylum when it was four-month-old. Grosinger took the dog home two months later and had a wheelchair manufactured for it. (Photo by Heinz-Peter Bader/Reuters)

A street actor dressed as a devil frightens children in downtown Prague in Prague, Czech Republic, Monday, December 5, 2016. On the eve of St. Nicholas, Czechs traditionally celebrate by dressing up as Devils, Angels and St. Nicholas, and visiting children in their homes handing out small presents, coal, potatoes or other gifts. (Photo by Petr David Josek/AP Photo)

In this picture taken on November 28, 2016, a hot-air balloon carrying tourists sails over the archeological site at sunrise in Bagan. Located in central Myanmar, Bagan is home to more than 2,000 ancient Buddhist monuments deeply revered in the Buddhist-majority nation and is one of the country's most popular tourist destinations. (Photo by Dale De La Rey/AFP Photo)