Helium ions reveal how viruses attack bacteria

Bacteria and viruses can be imaged with helium ions in contrast to electrons which are the standard workhorse in nanoscale microscopy, report scientists. Helium ions, being more massive than electrons, can be focused to a much tighter spot down to the atomic length scales. By measuring the electrons generated by the ion bombardment, an image can be formed from the sample with biological features visible below the nanometer (one billionth of a meter) length.