#nonius

In birth order of their eponyms:

Purbach crater is named after Austrian astronomer Georg von Peuerbach (1423-1461) who aimed at making astronomy accessible for the average European during the Renaissance with his textbook, Theoricae Novae Planetarum.

Walther crater is named after the German merchant Bernhard Walther (1430-1504) who was a noted observer of the motions of the planets.

Regiomontanus crater is named after German mathematician Johannes Müller von Königsberg (1436-1476) who helped develop the heliocentric theory of the solar system with trigonometry.

Orontius crater is named after the French mathematician Oronce Finé (1494-1555) who published an astronomy textbook De mundi sphaera which guided readers on the use of equipment and proper astronomy methods.

Nonius crater is named for Pedro Nunes (1502-1578), a Portuguese mathematician who used trigonometry to make improvements to the geocentric model of the solar system.

Hell crater is not named after the land of Satan, but instead is named after Hungarian astronomer Maximilian Hell (1720-1792) who was the director of the Vienna Observatory and observed the 1769 transit of Venus.

Lexell crater is named after the Finnish astronomer Andres Johan Lexell (1740-1784), a prolific member of the Russian Academy of Sciences who made important discoveries in celestial mechanics. He was the first to prove that Uranus was a planet rather than a comet.

Miller crater is named after William Allen Miller (1817-1870), a British chemist who aided William Huggins in studying the spectra of astronomical objects, primarily stars.

Huggins crater is named after the British astronomer William Huggins (1824-1910) who pioneered the realm of astronomical spectroscopy, becoming the first to take the spectrum of a planetary nebula.

Bell crater is named after none other than Canadian inventor Alexander Graham Bell (1847-1922) most famous for inventing the telephone, but who also had inventions in aeronautics.

Deslandres crater is named for Henri Alexandre Deslandres (1853-1948), a French astronomer who was the director of the Paris Observatories and carried out studies on the atmosphere of the Sun.