The results of the newest investigations carried out by scientists from the Institute of Nuclear Physics PAN shed new light on the processes of accumulation of plutonium isotopes on glaciers of the Southern Hemisphere. Analyses of samples of cryoconite, a sediment that accumulates on glaciers, reveal not only differences in concentrations between the hemispheres but also indicate unprecedented isotope anomalies that may be related to accidents such as the fall of the Mars-96 spacecraft.