So, by the mid-17th century the Russian people had established the borders of their country close to the modern ones, and explored almost the whole of Siberia, except eastern Kamchatka and some regions north of the Arctic Circle. The conquest of Kamchatka would be completed later, in the early 18th century by Vladimir Atlasov, while the discovery of the Arctic coastline and Alaska would be nearly completed by the Great Northern Expedition in 1733–1743. The expedition allowed cartographers to create a map of most of the northern coastline of Russia, thanks to the results brought by a series of voyages led by Fyodor Minin, Dmitry Ovtsyn, Vasili Pronchishchev, Semyon Chelyuskin, Dmitry Laptev and Khariton Laptev. At the same time, some of the members of the newly founded Russian Academy of Sciences traveled extensively through Siberia, forming the so-called Academic Squad of the Expedition. They were Johann Georg Gmelin, Daniel Gottlieb Messerschmidt and others, who became the first scientific explorers of Siberia.