Legacy of the Roman Empire learned classes throughout the Middle Ages; this is especially seen during the Renaissance and Baroque periods. Books which had a revolutionary impact on science, such as Nicolaus Copernicus' "De revolutionibus orbium coelestium" (1543), were composed in Latin. This language was not supplanted for scientific purposes until the 18th century, and for formal descriptions in zoology, as well as botany - it survived to the later 20th century. The modern international Binomial nomenclature holds to this day: the scientific name of each species is classified by a Latin or Latinized name. Today the Romance languages, which comprise all languages that descended
Age of the Earth it would take for the near-surface to cool to its present temperature. His calculations did not account for heat produced via radioactive decay (a process then unknown to science) or, more significantly, convection inside the Earth, which allows more heat to escape from the interior to warm rocks near the surface. Even more constraining were Kelvin's estimates of the age of the Sun, which were based on estimates of its thermal output and a theory that the Sun obtains its energy from gravitational collapse; Kelvin estimated that the Sun is about 20 million years old. Geologists such as Charles Lyell