In Mexico, mothers of the missing turn to drones to look for unmarked graves

Maria Aguilar has been searching for her son for over a decade. Now Aguilar and the "missing persons" collective she founded will be armed in their search with new technology – drones mounted with thermosensitive cameras that can show distortions in the soil which could point to an unmarked grave. Chemical detectors inserted in the ground can then highlight biological changes in the soil that could also be an indicator of human remains – such as unusually high nitrogen and humidity levels – and help narrow down potential search areas.