Template:POTD/2007-02-28

The first of a magnification series of a snow crystal (view the entire series) using a low temperature scanning electron microscope with magnification up to 100,000X, compared to 30X – 500X available with light microscopes. Snow samples are very fragile and exposure to the light necessary to photograph them, using light microscopes, can damage the crystals and even melt them. A low temperature SEM operating at −170°C avoids disturbing the structure.

Photo credit: Agricultural Research Service
Archive – More featured pictures...