Readers react to neutron imaging and the expanding definition of loneliness

A peek inside

Neutron tomography can help scientists capture 3-D images of the insides of fossils and artifacts without damaging them. The technique can uncover hidden features within dense material that X-ray scanning can’t detect, James R. Riordon reported in “Seeing into the past” (SN: 11/4/23, p. 18).

Reader Rob Janes asked how the 3-D images are captured.

In neutron tomography, scientists blast beams of neutrons at an object they want to study, Riordon says. Detectors on the other side of the object record the proportion of neutrons that make it through without being reflected or absorbed along the way.