Johannes Stadius or Estadius (

Dutch Dutch commonly refers to: * Something of, from, or related to the Netherlands * Dutch people () * Dutch language () Dutch may also refer to: Places * Dutch, West Virginia, a community in the United States * Pennsylvania Dutch Country People E ...

: ''Jan Van Ostaeyen''; French: ''Jean Stade'') (ca. 1 May 1527 – 17 June 1579), was a

Flemish Flemish (''Vlaams'') is a Low Franconian dialect cluster of the Dutch language. It is sometimes referred to as Flemish Dutch (), Belgian Dutch ( ), or Southern Dutch (). Flemish is native to Flanders, a historical region in northern Belgium; ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

, astrologer, and

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

. He was one of the important late 16th-century makers of

ephemerides In astronomy and celestial navigation, an ephemeris (pl. ephemerides; ) is a book with tables that gives the trajectory of naturally occurring astronomical objects as well as artificial satellites in the sky, i.e., the position (and possibly ...

, which gave the positions of astronomical objects in the sky at a given time or times.

Life

Born ''Jan Van Ostaeyen'' in the town of

Loenhout Loenhout is a village and '' deelgemeente'' (sub-municipality) of the municipality of Wuustwezel in the province of Antwerp, Belgium. The village is located near the Dutch border, and about north-east of the city of Antwerp. History The are ...

(''Loennouthesius'', meaning 'from Loenhout', is sometimes appended to his Latin surname) in the

Duchy of Brabant The Duchy of Brabant was a State of the Holy Roman Empire established in 1183. It developed from the Landgraviate of Brabant and formed the heart of the historic Low Countries, part of the Burgundian Netherlands from 1430 and of the Habsburg Neth ...

, Stadius grew up in the ''Schaliënhuis'' on the old Dorpsstraat, which was one of the oldest houses in Loenhout (today a tavern and restaurant). Not much else is known regarding his youth besides the fact that his parents were not married to each other. After receiving his education at the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

school of

Brecht Eugen Berthold Friedrich Brecht (10 February 1898 – 14 August 1956), known professionally as Bertolt Brecht, was a German theatre practitioner, playwright, and poet. Coming of age during the Weimar Republic, he had his first successes as a p ...

, Stadius studied mathematics,

geography Geography (from Greek: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, an ...

, and

history History (derived ) is the systematic study and the documentation of the human activity. The time period of event before the invention of writing systems is considered prehistory. "History" is an umbrella term comprising past events as well ...

at the Old University of Leuven, where one of his teachers was

Gemma Frisius Gemma Frisius (; born Jemme Reinerszoon; December 9, 1508 – May 25, 1555) was a Frisian physician, mathematician, cartographer, philosopher, and instrument maker. He created important globes, improved the mathematical instruments of his d ...

. After completing his studies, he became a professor of mathematics at his alma mater. In 1554 he left his home country and travelled to

Turin Turin ( , Piedmontese: ; it, Torino ) is a city and an important business and cultural centre in Northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The ...

, where he enjoyed the patronage of the powerful Duke of Savoy. Stadius subsequently worked in

Cologne Cologne ( ; german: Köln ; ksh, Kölle ) is the largest city of the German western state of North Rhine-Westphalia (NRW) and the fourth-most populous city of Germany with 1.1 million inhabitants in the city proper and 3.6 millio ...

Brussels Brussels (french: Bruxelles or ; nl, Brussel ), officially the Brussels-Capital Region (All text and all but one graphic show the English name as Brussels-Capital Region.) (french: link=no, Région de Bruxelles-Capitale; nl, link=no, Bruss ...

and

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), ma ...

. In Paris, he debated with the trigonometrist Maurice Bressieu of

Grenoble lat, Gratianopolis , commune status = Prefecture and commune , image = Panorama grenoble.png , image size = , caption = From upper left: Panorama of the city, Grenoble’s cable cars, place Saint- ...

and made

astrological Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that claim to discern information about human affairs and terrestrial events by studying the apparent positions of celestial objects. Dif ...

predictions for the French court. In his ''Tabulae Bergenses'' (1560), Stadius calls himself both royal mathematician (of Philip II of Spain) and mathematician to the Duke of Savo

''Ephemerides''

During his stay in Brussels Stadius published his first work, the ''Ephemerides novae et auctae'', first published by the publisher Arnold Birckmann of

in 1554. An '' ephemeris'' (plural: ''ephemerides'') (from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

word ''ephemeros'', "daily") was, traditionally, a table providing the positions (given in a Cartesian coordinate system, or in right ascension and declination or, for astrologers, in

longitude Longitude (, ) is a geographic coordinate that specifies the east– west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek lette ...

along the

zodiac The zodiac is a belt-shaped region of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The pat ...

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic agains ...

), of the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

, 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 ...

, and the

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

s in the

sky The sky is an unobstructed view upward from the surface of the Earth. It includes the atmosphere and outer space. It may also be considered a place between the ground and outer space, thus distinct from outer space. In the field of astronomy, ...

at a given moment in

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, ...

; the astrological positions are usually given for either

noon Noon (or midday) is 12 o'clock in the daytime. It is written as 12 noon, 12:00 m. (for meridiem, literally 12:00 noon), 12 p.m. (for post meridiem, literally "after noon"), 12 pm, or 12:00 (using a 24-hour clock) or 1200 ( military time). Sola ...

or midnight depending on the particular ephemeris that is used. This work posited a link between mathematics and medicine and was influential on

Tycho Brahe Tycho Brahe ( ; born Tyge Ottesen Brahe; generally called Tycho (14 December 154624 October 1601) was a Danish astronomer, known for his comprehensive astronomical observations, generally considered to be the most accurate of his time. He was ...

and

Nostradamus Michel de Nostredame (December 1503 – July 1566), usually Latinised as Nostradamus, was a French astrologer, apothecary, physician, and reputed seer, who is best known for his book '' Les Prophéties'' (published in 1555), a collection ...

. Stadius had been encouraged to publish the ''Ephemerides'' by his old teacher

. Frisius had in a letter written in 1555 urged Stadius not to be afraid of being accused of believing in a moving earth and a stationary sun (i.e. the theory of

Copernicus Nicolaus Copernicus (; pl, Mikołaj Kopernik; gml, Niklas Koppernigk, german: Nikolaus Kopernikus; 19 February 1473 – 24 May 1543) was a Renaissance polymath, active as a mathematician, astronomer, and Catholic canon, who formulated ...

) or of abandoning the medieval Alfonsine Tables in favor of his own observations. In this letter Frisius further wrote that the system devised by

gave a better understanding of planetary distances, as well as of certain features of retrograde motion. Frisius' letter was published in several editions of the ''Ephemerides''.

Death and legacy

Stadius died in Paris where he is buried. The inscription on his epitaph states that he died on 17 June 1579 and that he had lived for nearly 52 years and 2 months. Stadius' estimated birth date of 1 May 1527 is based on this inscriptio

The

lunar crater Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, all of which were formed by impacts. The International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated. History The wor ...

Stadius is named after Stadius.

External links

Prospector: Johannes Stadius

Flapuit: Johannes Stadius

*James H. Holden: A History of Horoscopic
AstrologySteven Vanden Broecke: The Limits of Influence: Pico, Louvain, and the Crisis of Renaissance Astrology
*(in Dutch

Joannes Stadius

Life

''Ephemerides''

Death and legacy

External links

Further reading