- Jeremiah Horrocks
Infobox Scientist
name = Jeremiah Horrocks
box_width =
image_width = 240px
caption = making the first observation of
the transit of Venus in 1639
birth_date = 1618
birth_place = Lower Lodge,Otterspool ,Toxteth Park , nrLiverpool ,Lancashire ,England
death_date = death date and age|1641|01|03|1618|01|04
death_place =Toxteth Park , nrLiverpool ,Lancashire ,England
residence =England
citizenship =
nationality = English
ethnicity =
field =
work_institutions =
alma_mater =
doctoral_advisor =
doctoral_students =
known_for =Astronomy
author_abbrev_bot =
author_abbrev_zoo =
influences =
influenced =
prizes =
footnotes =Jeremiah Horrocks (1618 –
January 3 ,1641 ), sometimes given as Jeremiah Horrox (the Latinised version that he used on the Emmanuel College register and in his Latin manuscripts), [http://www.transit-of-venus.org.uk/conference/history.html footnote 1 Retrieved2007-12-08 ] [http://www.salfordastro.org.uk/crabtree/crabtree2.html Retrieved2007-12-08 ] was an Englishastronomer who was the only person to predict, and one of only two people to observe and record, thetransit of Venus of 1639.Horrocks was born in Lower Lodge,
Otterspool inToxteth Park , nearLiverpool ,Lancashire . His father was a smallfarmer ; his uncle was awatchmaker ; he was relatively poor during his entire brief life. He joined Emmanuel College onMay 11 ,1632 and matriculated as a member of theUniversity of Cambridge onJuly 5 ,1632 as asizar . In 1635 he left without formally graduating, presumably due to the cost of continuing his studies. The traditional view is that he supported himself financially by holding a curacy inMuch Hoole , nearPreston inLancashire , but there is little evidence for this. According to local tradition in Much Hoole, he lived at Carr House, a substantial property owned by theStones family who were prosperous farmers and merchants, and was a tutor for the Stones children. He may have been aCalvinist and, through his connection with Emmanuel College, aPuritan , although there is little evidence of his religious convictions. [ [http://galileo.rice.edu/Catalog/NewFiles/horrocks.html Jeremiah Horrocks; The Galileo Project] Retrieved2007-12-08 ]At Cambridge, he became familiar with the works of
Johannes Kepler ,Tycho Brahe , and others. Horrocks read most of the astronomical treatises of his day, found the weaknesses in them and was suggesting new lines of research by the age of seventeen. He was the first to demonstrate that theMoon moved in an elliptical path around theEarth , he wrote a treatise on Keplerian astronomy and began to explore mathematically the properties of the force that later became known asgravity .Sir Isaac Newton acknowledged Horrocks's work as the bridge which connected him withCopernicus ,Galileo ,Brahe andKepler . [http://www.longtononline.co.uk/his_horrocks.html Retrieved2007-11-19 ] Horrocks was convinced that Lansberg's tables were inaccurate when Kepler predicted that a near-miss of a transit ofVenus would occur in 1639. Horrocks believed that the transit would indeed occur, having made his own observations of Venus for years.Horrocks focused the image of the Sun through a simple
telescope onto a piece of card, where the image could be safely observed. From his location in Much Hoole, he calculated that the transit was to begin at approximately 3:00 pm onNovember 24 ,1639 (Julian calendar , orDecember 4 in theGregorian calendar ). The weather was cloudy, but he first observed the tiny black shadow of Venus crossing the Sun on the card at about 3:15 pm, and observed for half an hour until sunset. The 1639 transit was also observed by his friend and correspondent,William Crabtree , from his home inSalford .Horrocks' observations allowed him to make a well-informed guess as to the size of Venus (previously thought to be larger and closer to Earth), as well as to make an estimate of the distance between the
Earth and the Sun. His figure of 59 million miles (95 million kilometres, 0.63 AU) was far from the 93 million miles (150 million kilometers) that it is known to be today but it was a more accurate figure than any suggested up to that time. A treatise by Horrocks, "Venus in sub sole visa" ("Venus in transit across the Sun") was published byJohannes Hevelius at his own expense in 1662.This paper, which caused great excitement when revealed to members of the
Royal Society 20 years after it was written, contained much evidence of Horrocks' enthusiastic and romantic nature, including humorous comments and passages of original poetry. When speaking of the century separating Venetian transits, he rhapsodised, "Thy return/ Posterity shall witness; years must roll/ Away, but then at length the splendid sight/ Again shall greet our distant children's eyes."Horrocks also put his energies into the highly complex task of determining
the Moon's orbit . He correctly hypothesised that the moon's orbit was elliptical rather than circular, and he anticipatedIsaac Newton in suggesting an influence on the moon's orbit from the sun as well as the earth. In the final months of his life he also made detailed study oftides , in an attempt to explain the nature of lunar causation of tidal movements.Horrocks returned to Toxteth Park sometime in the summer of 1640 and died suddenly and from unknown causes on the
3 January 1641 , aged only 22. As expressed by his astronomer friendWilliam Crabtree , "What an incalculable loss!" ("Opera Posthuma of Jeremiah Horrocks", ed. John Wallis, London, 1672.)Further reading
* Peter Aughton: "The transit of Venus: the brief, brilliant life of Jeremiah Horrocks, father of British astronomy". London: Weidenfeld & Nicolson, 2004. ISBN 0-297-84721-X.
* Allan Chapman, "Jeremiah Horrocks, the transit of Venus, and the 'New Astronomy' in early seventeenth-century England", "Quarterly Journal of the Royal Astronomical Society", 31 (1996): 333-357.
* Marston, P. The History of Jeremiah Horrocks http://www.transit-of-venus.org.uk/conference/history.htmlReferences
External links
* [http://www.longtononline.co.uk/his_horrocks.html Jeremiah Horrocks: His Origins and Education]
*" [http://www.sil.si.edu/exhibitions/chasing-venus/intro.htm Chasing Venus, Observing the Transits of Venus] " Smithsonian Institution Libraries
* [http://www.transit-of-venus.org.uk/conference/history.html History of Jeremiah Horrocks]
* [http://news.bbc.co.uk/1/hi/england/lancashire/3776889.stm BBC report: Celebrating Horrocks' half hour]
*
* [http://www.ucl.ac.uk/sts/nk/birth.htm Horrocks and the Dawn of British Astronomy]
Wikimedia Foundation. 2010.