Credit: JOHN HART/SAMEH TAWFICK/MICHAEL DE VOLDER/WILL WALKER/WWW.NANOBLISS.COM

The giant granite sculptures of George Washington — the first president of the United States — and three of his successors at Mount Rushmore are some of the most famous images in the world. It took more than 14 years and some 400 workers to complete the 18-metre-high sculptures. Now Barack Obama — who will become the 44th president of the US — has been immortalized in carbon nanotubes barely a week after he was elected. John Hart of the University of Michigan and co-workers grew the nanotubes on a silicon wafer patterned with an iron catalyst to produce a variety of images (www.nanobama.com). In the electron micrograph shown here, each face contains about 150 million nanotubes. “We had no political message in mind,” says Hart, “other than to draw attention to the science and applications of nanostructures in the hope that people who wouldn't otherwise read about nanotechnology may want to learn a bit more.”