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There’s more science visualization going around to feed those hungry eyes!

The winning image at the 2005 Visions of Science Photographic Awards is a Scanning Electron Microscope (SEM) image of two food items we use everyday. Take a guess, click through to the link and leave a message here to brag if you got it right.

There are tons of other brilliant images in the archives of the Visions of Science Photographic Awards promoted by Novartis and The Daily Telegraph.

Visions of Science is a photographic awards scheme organised by Novartis Pharmaceuticals to encourage ongoing discussion about science.

So, what is a Vision of Science? To the judges of the Awards, a Vision of Science is an attention-grabbing image that gives new insight into the world of science and the workings of nature. It may show something never seen before, it may explain a scientific phenomenon, it may illustrate scientific data or it may simply be an image that shows the beauty of science.

Quite a few images in the contest are taken using a Scanning Electron Microscope better known simply as SEM. The SEM operates by using a beam of electrons to scan the surface of the subject. The beam-subject interactions gives rise to a stream of secondary electrons that are used to generate an image.

Electron Microscopy is a powerful tool for looking at vanishingly small length scales. The primary advantage of using electrons over visible light arises from the wave-particle nature of fast moving electrons. Visible light as we know, comes in flavors (wavelengths) ranging from 4000-7000 Angstroms. Compare this to the wavelength of electrons excited to a mere 50 KeV (typical SEM use) : 24 Angstroms.

The focussing electronics that go with the SEM instrument are also critical in achieving the desired resolution. Modern SEM instruments have typical resolutions down to 5nm!

As my favorite example goes, at that resolution, a single strand of hair will look like a thick fat rope!