Many of the activities connected to the sea are closely related to science and technology. Science is present in cartography as well as in the instruments used for determining one’s position at sea. In these cases, however, science and technology play an "auxiliary role”. However, in some circumstances, Navy officers and ships have conducted tasks directly related to science.
Due to their highly scientific training, naval officers were often appointed to conduct scientific tasks. These tasks could be developed both at sea, particularly in terms of hydrographic and oceanographic research, as well as onshore, in landmass reconnaissance and geodetic surveys, or even issues related with meteorology or astronomy.
The Navy’s scientific activity was especially important in the Portuguese overseas territories. The best way to reach them, if not the only one, was by sea. Due to this, Navy officers frequented the overseas territories regularly, and thus were those who best knew these territories. For this reason, the Navy played a key role in the study of the overseas territories, either maritime or terrestrial.