Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

An internally displaced Afghan girl holds a child at a refugee camp in Kabul, Afghanistan May 31, 2016. (Photo by Mohammad Ismail/Reuters)

A girl salutes to visitors before a show at the Mangyongdae Children's Palace in central Pyongyang, North Korea May 5, 2016. Pyongyang held a gala of song and dance performances by local school children on May 5 for visiting delegations of foreign journalists and tourists at the Mangyongdae Children's Palace. The event included orchestral, choir, and acrobatic performances, many of them with political undertones. The Seventh Worker's Party Congress commences on May 6, 2016. (Photo by Damir Sagolj/Reuters)

Most people know Nikon as a purveyor of pro and consumer-grade digital cameras. But the company's expertise with optics bleeds over into related markets – it's one of the science community's major suppliers of microscopes. And each year the company asks the community to send it some of their favorite images of tiny objects. A panel of scientists and journalists have chosen the best of this past year's submissions, which Nikon has placed on its Small World site.

Photo: Honorable Mention. “Snow crystal, illuminated with colored lights (5x)”. (Photo by Dr. Kenneth Libbrecht, California Institute of Technology (Caltech), Department of Physics, Pasadena, California, USA)

A Femen activist is led away by French police in Henin-beaumont, northern France, Sunday, May 7, 2017. Voters across France are choosing a new president in an unusually tense and important election that could decide Europe's future, making a stark choice between pro-business progressive candidate Emmanuel Macron and far-right populist Marine Le Pen. (Photo by Francois Mori/AP Photo)

The Pink Floyd inflatable pig floats next to Broadcasting House to promote their new exhibition at the V&A museum, in London, Britain May 10, 2017. (Photo by Neil Hall/Reuters)

Extras in the arena of the “Fete des Vignerons” (winegrowers' festival in French), during the last rehearsal in Vevey, Switzerland, 17 July 2019. Organized by the brotherhood of winegrowers, the event will celebrate winemaking from 18 July to 11 August. The arena has a capacity of 20,000 spectators and hosts a giant central LED floor of approximately 800 square meters. (Photo by Laurent Gilliéron/EPA/EFE)

Aliana Alexis of Haiti stands on the concrete slab of what is left of her home after destruction from Hurricane Dorian in an area called “The Mud” at Marsh Harbour in Great Abaco Island, Bahamas on September 5, 2019. Hurricane Dorian lashed the Carolinas with driving rain and fierce winds as it neared the US east coast Thursday after devastating the Bahamas and killing at least 20 people. (Photo by Al Diaz/Zuma Press via AFP Photo)