Cryptic (geology)
The Cryptic era is an informal term for the earliest geologic evolution of the Earth and Moon. It is the oldest (informal) era of the Hadean eon, and it is commonly accepted to have begun close to 4533 million (about 4.533 billion) years ago when the Earth and Moon formed. No samples exist to date the transition between the Cryptic era and the following Basin Groups era for the Moon (see also Pre-Nectarian), though sometimes it is stated that this era ended 4150 million years ago for one or both of these bodies. Neither this time period, nor any other Hadean subdivision, has been officially recognized by the International Commission on Stratigraphy.
Fifth-century Athens
Fifth-century Athens is the Greek city-state of Athens in the time from 480–404 BC. This was a period of Athenian political hegemony, economic growth and cultural flourishing formerly known as the Golden Age of Athens with the later part The Age of Pericles. The period began in 478 BC after defeat of the Persian invasion, when an Athenian-led coalition of city-states, known as the Delian League, confronted the Persians to keep the liberated Asian Greek cities free. After peace was made with Persia in the mid 5th century BC, what started as an alliance of independent city-states became an Athenian empire when Athens abandoned the pretense of parity among its allies and relocated the Delian League treasury from Delos to Athens, where it funded the building of the Athenian Acropolis and put half its population on the public payroll and maintained dominating naval power in the Greek world. With the empire's funds, military dominance and its political fortunes guided by statesman and orator Pericles, Athens produced some of the most influential and enduring cultural artifacts of the Western tradition. The playwrights Aeschylus, Sophocles and Euripides all lived and worked in 5th century BC Athens, as did the historians Herodotus and Thucydides, the physician Hippocrates, and the philosophers Plato and Socrates. Athens' patron goddess was Athena, from whom they derived the name.