Petrus Astronomus Astronomical clock in Uppsala Cathedral

Petrus Astronomus, O.Ss.S., (died after 1513), a German by birth, was a

Bridgettine The Bridgettines, or Birgittines, formally known as the Order of the Most Holy Savior (; abbreviated OSsS), is a monastic religious order of the Catholic Church founded by Saint Birgitta or Bridget of Sweden in 1344, and approved by Pope Urban ...

monk A monk (, from el, μοναχός, ''monachos'', "single, solitary" via Latin ) is a person who practices religious asceticism by monastic living, either alone or with any number of other monks. A monk may be a person who decides to dedica ...

Vadstena Abbey The Abbey Pax Mariae ( la, Monasterium sanctarum Mariæ Virgìnis et Brigidæ in Vatzstena), more commonly referred to as Vadstena Abbey, situated on Lake Vättern in the Diocese of Linköping, Sweden, was the motherhouse of the Bridgettine Orde ...

Vadstena Vadstena () is a locality and the seat of Vadstena Municipality, Östergötland County, Sweden, with 5,613 inhabitants in 2010. From 1974 to 1979 Vadstena was administered as part of Motala Municipality. Despite its small population, Vadstena is ...

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

. In 1506, he created an

astronomical clock An astronomical clock, horologium, or orloj is a clock with special mechanisms and dials to display astronomical information, such as the relative positions of the Sun, Moon, zodiacal constellations, and sometimes major planets. Definition ...

for the

Uppsala Cathedral Uppsala Cathedral ( sv, Uppsala domkyrka) is a cathedral located between the University Hall of Uppsala University and the Fyris river in the centre of Uppsala, Sweden. A church of the Church of Sweden, the national church, in the Lutheran tra ...

, which, in addition to the hours and minutes of the day, also illustrated the

moon phase Concerning the lunar month of ~29.53 days as viewed from Earth, the lunar phase or Moon phase is the shape of the Moon's directly sunlit portion, which can be expressed quantitatively using areas or angles, or described qualitatively using the t ...

and the movements of the planets. The clock was repaired by

Christopher Polhem Christopher Polhammar (18 December 1661 – 30 August 1751) better known as Christopher Polhem (), which he took after his ennoblement in 1716, was a Swedish scientist, inventor and industrialist. He made significant contributions to the economi ...

in the 17th century but destroyed in a fire in 1702. He first appears by name as a lecturer in

astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...

Uppsala University Uppsala University ( sv, Uppsala universitet) is a public university, public research university in Uppsala, Sweden. Founded in 1477, it is the List of universities in Sweden, oldest university in Sweden and the Nordic countries still in opera ...

, where between 1508 and 1509 he conducted a series of lectures. He is sometimes erroneously confused for

Conrad Dasypodius Conrad Dasypodius (1532 – 26 April 1600) was a professor of mathematics in Strasbourg, Alsace. He was born in Frauenfeld, Thurgau, Switzerland. His first name was also rendered as Konrad or Conradus or Cunradus, and his last name has been al ...

who constructed the astronomic clockwork in the Strassbourg cathedral.

References

German emigrants to Sweden 16th-century German astronomers 16th-century Swedish astronomers Bridgettine monks German Roman Catholics {{Europe-astronomer-stub