{"id":2435,"date":"2012-02-10T17:15:40","date_gmt":"2012-02-10T17:15:40","guid":{"rendered":"http:\/\/www.dwc.knaw.nl\/?page_id=2435"},"modified":"2012-02-15T13:24:50","modified_gmt":"2012-02-15T13:24:50","slug":"huygens-discovery-of-a-ring-around-saturn","status":"publish","type":"page","link":"https:\/\/dwc.knaw.nl\/en\/biografie\/christiaan-huygensweb\/wetenschappelijk-werk\/huygens-discovery-of-a-ring-around-saturn\/","title":{"rendered":"Huygens&#8217; discovery of a ring around Saturn"},"content":{"rendered":"<p>The planet Saturn was a significant problem for astronomers in the  first decades of the seventeenth century. Viewed through the first  telescopes, the planet displayed a strange, irregular form, a form that  also changed with the passing of time. Various explanations were offered  for this phenomenon, but it was Huygens who finally found the solution  to the puzzle.<\/p>\n\n<p>While observing Saturn through his telescope,  Huygens developed an explanation for the seemingly fluctuating form of  this planet. Galileo was the first to observe these constantly changing  \u2018ears of Saturn\u2019.<\/p>\n\n<p>In March 1656 it became clear that Huygens had  discovered something important, when he published a pamphlet reporting  his discovery of a moon near the planet Saturn a year earlier. At the  time, Saturn was the furthest planet from the earth known in our solar  system.<\/p>\n\n<p>However, when Huygens published his discovery of the  Saturn moon (named Titan), he was not yet absolutely sure that his ring  hypothesis was correct. Huygens announced his hypothesis in the same  manner as he had announced the discovery of Titan; in the form of an  anagram. He could then make the solution known at a later date, when he  was sure he was right.<\/p>\n\n<p>No copies have survived of the original  pamphlet that Huygens distributed among his colleagues. However, the  publisher Adriaan Vlacq included the text of the pamphlet as an insert  in the back of Pierre Borel\u2019s book about the discovery of the telescope (<em>De vero telescopii inventore<\/em>), which also appeared in March 1656.<\/p>\n\n<p>In  March 1658, three years after his initial observation and two years  after his publication, Huygens was sure enough of himself to reveal the  meaning of his second anagram. He wrote to his correspondent J.  Chapelain that the anagram represented the following sentence in Latin:  \u2018ANNULO CINGITUR TENUI, PLANO, NUSQUAM COHAERENTE AD ECLIPTICAM  INCLINATO\u2019, which means \u2018it is surrounded by a ring, thin and flat,  never touching, oblique in relation to the ecliptic\u2019. Huygens published  this solution to the anagram, which could not possibly have been solved  by anybody else, in 1659 in his book <a href=\"http:\/\/www.sil.si.edu\/DigitalCollections\/HST\/Huygens\/huygens.htm\" target=\"_blank\"><em><strong>Systema Saturnium<\/strong><\/em><\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The planet Saturn was a significant problem for astronomers in the first decades of the seventeenth century. Viewed through the first telescopes, the planet displayed a strange, irregular form, a form that also changed with the passing of time. Various explanations were offered for this phenomenon, but it was Huygens who finally found the solution [&hellip;]<\/p>","protected":false},"author":3,"featured_media":0,"parent":64,"menu_order":4,"comment_status":"open","ping_status":"open","template":"","meta":{"_links_to":"","_links_to_target":""},"_links":{"self":[{"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/pages\/2435"}],"collection":[{"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/comments?post=2435"}],"version-history":[{"count":2,"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/pages\/2435\/revisions"}],"predecessor-version":[{"id":2478,"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/pages\/2435\/revisions\/2478"}],"up":[{"embeddable":true,"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/pages\/64"}],"wp:attachment":[{"href":"https:\/\/dwc.knaw.nl\/en\/wp-json\/wp\/v2\/media?parent=2435"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}