while studying the works of the contemporaneous climatologist julius von hann, milanković noticed a significant issue, which became one of the major objects of his scientific research: a mystery ice age. the idea of possible astronomically-related climate changes was first considered by astronomers (john herschel, 1792–1871) and then postulated by geologists (louis agassiz, 1807–1873). in parallel, there were also several attempts to explain the climate change by the influence of astronomical forces (the most comprehensive of them was the theory put forward by james croll in the 1860s). milanković studied the works of joseph adhemar whose pioneering theory on the astronomical origins of ice ages were formally rejected by his contemporaries and james croll whose work was effectively forgotten about even after acceptance by contemporaries such as charles darwin. despite having valuable data on the distribution of ice ages on alps, climatologists and geologists could not discover the basic causes – that is, the different insolations of the earth during past ages remained beyond the scope of these sciences. but milanković decided to follow their path and attempt correctly to calculate the magnitude of such influences. milanković sought the solution of these complex problems in the field of spherical geometry, celestial mechanics, and theoretical physics.