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“The advent of low temperature scanning EM led to a study by Bill Wergin and colleagues from NASA in which they collected samples from different types of snow cover found in the prairies, taiga (snow forest), and alpine environments. With snow depths up to a metre, various layers occurred in which the crystals underwent a change in their microscopic shape from the original freshly fallen crystals, to the development of flat faces and sharp edges. It is this metamorphosis of lying snow that determines the likelihood of avalanches, which can be predicted from the crystal structures at various depths. Although scanning EM (electron microscopy) is hardly available as a routine assay in distant mountain regions, this work helped in the use of microwave radiology investigation of the snow water equivalent in the snow pack, as large snow crystals scatter passive microwave more than small crystals. Smaller and more rounded crystals of snow do not interlock, and can slide more easily over each other, increasing the risk of avalanches.”

“At one end of the scale, astronomers search the heavens for new information about the universe, whilst at the other end, microscopists chase atoms and molecules to study defects in crystals or the basic processes of life. These investigations may be separated by more than twentyfold orders of magnitude, but are nevertheless driven by the same insatiable curiosity of the human psyche to explore beyond the vision of our own eyes.”

“With the advent of nanotechnology, microfabrication has produced novel manmade constructs called metamaterials which exhibit entirely new properties in terms of their effect on light, effects which are not found in conventional materials, or even in nature itself. Early in the 21st century, a chance observation showed that an ultrathin layer of silver on a flat sheet of glass would act like a lens, and from this point, the development of the ‘perfect’ or ‘superlens’ began, with the theoretical possibility to image details such as viruses in living cells with a light microscope, bypassing Abbe’s diffraction limit. Metamaterials have been produced that make this possible, as they have a property previously unimagined in optics, and not found in nature, which is a negative refractive index.”