Nonius is a

lunar Lunar most commonly means "of or relating to the Moon". Lunar may also refer to: Arts and entertainment * ''Lunar'' (series), a series of video games * "Lunar" (song), by David Guetta * "Lunar", a song by Priestess from the 2009 album ''Prior t ...

impact crater. It is located in the rugged southern highlands on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

's near side. It was named after 16th century Portuguese mathematician

Pedro Nunes Pedro Nunes (; Latin: ''Petrus Nonius''; 1502 – 11 August 1578) was a Portuguese mathematician, cosmographer, and professor, from a New Christian (of Jewish origin) family. Considered one of the greatest mathematicians of his time, Nunes ...

, Latinized as ''Nonius''. The northwestern side and about half the interior floor are overlain by the rim and outer

rampart Rampart may refer to: * Rampart (fortification), a defensive wall or bank around a castle, fort or settlement Rampart may also refer to: * "O'er the Ramparts We Watched" is a key line from "The Star-Spangled Banner", the national anthem of the ...

of the walled plain

Walther Walther is a masculine given name and a surname. It is a German form of Walter, which is derived from the Old High German ''Walthari'', containing the elements ''wald'' -"power", "brightness" or "forest" and ''hari'' -"warrior". The name was fir ...

. About half its diameter to the southeast is the smaller crater

Kaiser ''Kaiser'' is the German word for "emperor" (female Kaiserin). In general, the German title in principle applies to rulers anywhere in the world above the rank of king (''König''). In English, the (untranslated) word ''Kaiser'' is mainly ap ...

, and slightly farther to the south lies Fernelius. The surviving rim of this crater has been damaged by multiple impacts, including the merged pair of Nonius K and Nonius L across the northern rim. The surviving outline is more

hexagon In geometry, a hexagon (from Ancient Greek, Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple polygon, simple (non-self-intersecting) hexagon is 720°. Regular hexa ...

al in shape than round. The interior floor has an uneven surface, with low ridges and a crater-formed gouge in the western half.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Nonius.

References

* * * * * * * * * * * {{Commons category, Nonius (crater) Impact craters on the Moon