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Interview With Planet Hunter, Geoff Marcy
mindpixel writes "I was told as a child we'd never 'see' atoms or planets of other stars. Now with atomic force microscopes we 'see' atoms and with almost any telescope and statistics we 'see' planets. In the amazing online journal - Astrobiology - Planet-finding scientist, Geoff Marcy, describes just how it feels to find a new world."
Multiple techniques allow you to "see" atoms, including nuclear magnetic resonance (NMR) and x-ray crystallography. Electron microscopy generally is used for larger objects, at least in biochemical/biophysical applications as its resolution limit is somewhere around 1 nm, although recent innovations may have shrunk that somewhat. In comparison the diameter of a hydrogen atom is on the order of 0.1 nm. All three methods are highly indirect so the statement that you can't see atoms is still valid.
I routinely see crystal lattice images in TEMs (transmission electron microscopes). Perhaps this is what the parent poster remembers. Single crystal gold is often used to check performance and is quite easy to resolve .14 nm lattice spacings in higher end models. This isn't really resolving individual atoms though, but columns of atoms. It is possible though to view individual atoms, depending on your hardware and the element you're looking at. Google search for "individual atoms" "electron microscope".