An Atomic Force Microscope (AFM) image of an optical filter for ESA's Sentinel-2 mission, revealing the position of individual atoms across its surface. The AFM – whose inventor won the Nobel Prize for physics in 1986 – works in principle in the same way as an old-fashioned stylus across a record player, except the ‘profilometer’ in question has been sharpened to a nanometre-wide tip using techniques borrowed from the semiconductor industry, measuring roughly a single atom per second. The AFM can be used directly to gather height data or indirectly measuring material characteristics such as hardness, magnetism, intermolecular forces, electrical potential and thermal properties on the nano-scale.