This shows a false-color fluorescence image of a diamond surface. The small dark circular spots show nitrogen-vacancy (NV) centers that can be used as atomic-size detectors of magnetic fields. Individual NV centers are used to detect the weak magnetic fields emanating from the nuclei of hydrogen atoms in an organic sample. The vertical stripe is a microfabricated wire that transmits electromagnetic signals used to manipulate the NV centers and the hydrogen nuclei. The NV centers allow detection of magnetic resonance (the basis of MRI) in nanoscopic regions of the organic sample. This image relates to a paper that appeared in the Feb. 1, 2013, issue of Science, published by AAAS. The paper, by John Mamin at IBM Almaden Research Center in San Jose, Calif., and colleagues was titled, "Nanoscale Nuclear Magnetic Resonance with a Nitrogen-Vacancy Spin Sensor."