Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)

A schoolgirl stands next to the Kenya-Uganda railway line during the partial reopening of schools, after the government scrapped plans to cancel the academic year due to the coronavirus disease (COVID-19) pandemic, in Kibera slums of Nairobi, Kenya on October 12, 2020. (Photo by Thomas Mukoya/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 hot air balloon floats past an almost full rising moon on a warm fall evening near Encinitas, California October 5, 2014. (Photo by Mike Blake/Reuters)

Topless protesters from the organization PETA (People for the Ethical Treatment of Animals) stand with “banderillas” filled with red powder as about 100 people rally in front of the town hall square in Pamplona, Navarra, northern Spain, demonstrating against the treatment of fighting bulls in the Fiesta de San Fermin, 05 July 2017. The renowned eight-day festival made famous by Ernest Hemingway's 1926 novel “The Sun Also Rises” has running-with-the-bulls and a bullfight each day for the fair, which begins at noon on 06 July 2017. (Photo by Jim Hollander/EPA)

U.S. Secretary of State John Kerry stands inside the historic Shackleton hut near McMurdo Station, Antarctica, Friday, November 11, 2016. Kerry became the highest-ranking American official to visit Antarctica when he landed for a two-day trip on Friday. He's been hearing from scientists about the impact of climate change on the frozen continent. Kerry's aides described the trip as a learning opportunity for the secretary of state. He has been receiving briefings from scientists working to understand the effects of climate change on Antarctica. Kerry has made climate change an intensive focus of American diplomacy during his term, and had previously spent decades working on the issue as a U.S. senator. Trump has called climate change a hoax and said he would “cancel” U.S. involvement in the landmark Paris Agreement on global warming. (Photo by Mark Ralston/Pool Photo via AP Photo)

Four men dressed as zombies participate in a Zombie Walk procession in the streets of Paris October 12, 2013. (Photo by Benoit Tessier/Reuters)

In this January 25, 2013 photo, snake handler Saintilus Resilus holds a snake in front of his lips as he trains the snake to recognize his smell as he prepares for his street performances during the pre-Lenten Carnival season, at his home in Petionville, Haiti. Resilus sees himself as something of a performance artist, showing off with snakes and other animals that Haitians don't see every day, earning tips from impromptu audiences. (Photo by Dieu Nalio Chery/AP Photo via Matt Dayhoff)