Johannes Hevelius - Astronomy

Astronomy

Throughout his life, Hevelius took a leading part in municipal administration, becoming town councillor in 1651; but from 1639 on, his chief interest was astronomy. In 1641 he built an observatory on the roofs of his three connected houses, equipping it with splendid instruments, including ultimately a large Keplerian telescope of 45 m (150 ft) focal length, with a wood and wire tube he constructed himself. This may have been the longest "tubed" telescope before the advent of the tubeless aerial telescope.

The observatory was known by the name Sternenburg (Latin: Stellaeburgum; Polish: Gwiezdny Zamek) or "Star Castle" This private observatory was visited by Polish Queen Marie Louise Gonzaga on 29 January 1660. As a subject of the Polish Kings, Hevelius enjoyed the patronage of four subsequent kings of Poland, and his family was raised to the position of nobility by the King of Poland Jan Kazimierz in 1660, who previously visited his observatory in 1659. While the noble status was not ratified by the Polish Sejm Hevelius's coat of arms includes the distinctive Polish royal crown. The Polish King John III Sobieski who regularly visited Hevelius numerous times in years 1677-1683 released him from paying taxes connected to brewing and allowed his beer to be sold freely outside the city limits. In May 1679 the young Englishman Edmund Halley visited him as emissary of the Royal Society, whose fellow Hevelius had been since 1664. The Royal Society considers him one of the first German fellows. Małgorzata Czerniakowska (2005) writes that "Jan Heweliusz was the first Pole to be inducted into the Royal Society in London. This important event took place on 19th March 1664." Hevelius considered himself as being citizen of the Polish world (civis Orbis Poloniae) and stated in a latter dated from 9 January 1681 that he was Civis orbis Poloni, qui in honorem patriae suae rei Literariae bono tot labores molestiasque, absit gloria, cum maximo facultatum suarum dispendio perduravit-"citizen of Polish world who, for glory of his country and for the good of science, worked so much, and while not boasting much, executed his work with most effort per his abilities"

Halley had been instructed by Robert Hooke and John Flamsteed to persuade Hevelius to use telescopes for his measurements, yet Hevelius demonstrated that he could do well with only quadrant and alidade. He is thus considered the last astronomer to do major work without the use of a telescope.

Hevelius made observations of sunspots, 1642–1645, devoted four years to charting the lunar surface, discovered the Moon's libration in longitude, and published his results in Selenographia, sive Lunae descriptio (1647), a work which entitles him to be called "the founder of lunar topography."

He discovered four comets, in 1652, 1661 (probably Ikeya-Zhang), 1672 and 1677. These discoveries led to his thesis that such bodies revolve around the Sun in parabolic paths.

A halo phenomenon was observed by many in Danzig and described by Hevelius to pastor Georg Fehlau of St. Mary's church, titled Siebenfältiges Sonnenwunder oder sieben Nebensonnen, so in diesem 1661 Jahr den 20. Februar neuen Stils am Sonntage Sexagesima um 11 Uhr bis nach 12 am Himmel bei uns sind gesehen worden -"Sevenfold sun miracle or seven sun dogs which were seen in our skies on Sexagesima Sunday, 20th of February of the year 1661 from 11 o'clock until after 12 o'clock".

Katharine, his first wife, died in 1662, and a year later Hevelius married Elisabeth Hevelius née Koopmann, the young daughter of a merchant family. The couple had four children. Elisabeth supported him, published two of his works after his death, and is considered the first female astronomer.

His observatory, instruments and books were destroyed by fire on September 26, 1679. The catastrophe is described in the preface to his Annus climactericus (1685). He promptly repaired the damage enough to enable him to observe the great comet of December 1680. He named the constellation Sextans in memory of these lost instruments.

In late 1683, in commemoration of the victory of Christian forces led by Polish King John III Sobieski at the Battle of Vienna, he invented and named the constellation Scutum Sobiescianum (Sobieski's Shield), now called Scutum. This constellation first occurred publicly in his star atlas Firmamentum Sobiescianum, that was printed in his own house at lavish expense, and he himself engraved many of the printing plates.

His health had suffered from the shock of the 1679 fire, and he died on his 76th birthday, January 28, 1687. Hevelius was buried in St. Catherine's Church in his hometown.

Descendants of Hevelius live in Urzędów in Poland where they support local astronomy enthusiasts