Glowing-hot carbon nanotubes form an expanding orange ball in this image by Paul Marshall of Canada's Institute for Microstructural Sciences, a winner in the 2008 Small World photomicrography competition.
The nanotubes are elongated, hollow cylinders of carbon atoms. To make a carbon nanotube--just 1/50,000 the width of a human hair--a piece of carbon (graphite) must be heated, for example by lasers or electricity. And sometimes, Marshall says, the heated mass of nanotubes grows like a bulb in the spring.
Photograph by Paul Marshall/National Research Council Canada/photo courtesy of Nikon Small World