{"id":250373,"date":"2025-11-08T01:35:12","date_gmt":"2025-11-08T01:35:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/250373\/"},"modified":"2025-11-08T01:35:12","modified_gmt":"2025-11-08T01:35:12","slug":"how-a-medieval-oxford-friar-used-light-and-colour-to-find-out-what-stars-and-planets-are-made-of","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/250373\/","title":{"rendered":"How a medieval Oxford friar used light and colour to find out what stars and planets are made of"},"content":{"rendered":"

During the 1240s, Richard Fishacre, a Dominican friar at Oxford University, used his knowledge of light and colour to show that the stars and planets are made of the same elements found here on Earth. In so doing he challenged the scientific orthodoxy of his day and pre-empted the methods and discoveries of the 21st-century James Webb space telescope<\/a>.<\/p>\n

Following the Ancient Greek philosopher Aristotle, medieval physics affirmed that the stars and planets were made from a special celestial element \u2013 the famous \u201cfifth element\u201d<\/a> (quinta essentia) or \u201cquintessence\u201d. Unlike the four elements found here on Earth (fire, water, earth and air), this \u201cfifth element\u201d is perfect and unchanging.<\/p>\n

Fully transparent, it formed the basis of what were believed to be the nine concentric celestial \u201cspheres\u201d surrounding the Earth, as well as the various stars and planets attached to them. These, it was argued, were merely condensed versions of the \u201cfifth element\u201d, with each of the first seven spheres having its own planet, and the outermost eighth and ninth spheres containing the stars and heaven itself, respectively.<\/p>\n

\"A<\/p>\n

A medieval chart of the nine concentric celestial \u2018spheres\u2019 surrounding the earth.
\n Oxford University<\/a><\/p>\n

Colour, light and the stars<\/p>\n

Lacking access to telescopes and rock samples, Fishacre<\/a> \u2013 the first Dominican friar to teach theology at Oxford University \u2013 openly rejected the idea that the stars and planets were made from some special \u201cfifth element\u201d. In his opinion, they consisted of the same four elements found here.<\/p>\n

His reason for asserting this position was his understanding of how colour and light behave.<\/p>\n

Colour, Fishacre noted, is typically associated with opaque bodies. These, however, are always composite, meaning made up of two or more of the four terrestrial elements. When we look up at the stars and planets, however, we see that the light they emit often has a faint colour. Mars appears red, and Venus yellow, for example. This suggests, of course, that they are composite and thus made \u201cex quattuor elementis\u201d \u2013 \u201cout of the four elements\u201d.<\/p>\n

In Fishacre\u2019s opinion the surest proof that the stars and planets were not made of some special \u201cfifth element\u201d came from the Moon. It has a very definite colour, and, crucially, every so often it eclipses the Sun. Were it made from the transparent fifth element \u2013 even a highly condensed version of it \u2013 then surely the Sun\u2019s light would pass through it, just as it does a pane of glass. This, however, is not the case.<\/p>\n

The Moon, Fishacre reasoned, must therefore be made of the same elements found on Earth. And if this was true of the Moon, which is the lowest celestial body, then it must also be true of all the other stars and planets.<\/p>\n

\"The<\/p>\n

The James Webb space telescope confirmed what Richard Fishacre claimed about the composition of stars and planets 800 years earlier.
\n Shutterstock<\/a><\/p>\n

A brave move<\/p>\n

In arguing this, Fishacre knew that he was risking criticism. \u201cIf we posit this position,\u201d he wrote<\/a>, \u201cthen they, that crowd of Aristotelian know-it-alls (scioli aristoteli), will cry out and stone us\u201d.<\/p>\n

Sure enough, stones were thrown at Fishacre \u2013 and from high places.
\nIn 1250, his teaching was denounced at the University of Paris by St Bonaventure of Bagnoregio, a Franciscan friar who ridiculed in his lectures those \u201cmoderns\u201d like Fishacre who foolishly questioned Aristotle\u2019s teaching on the celestial fifth element.<\/p>\n

Contemporary astrophysics has, of course, vindicated Fishacre\u2019s position<\/a>. The stars and planets are not made of some special fifth element, but rather from many of the same metals and elements found here on our home planet. The James Webb space telescope, for example, recently established that the atmosphere of the Neptune-like exoplanet TOI-421 b<\/a>, some 244 light years away, contains high quantities of water and sulphur dioxide<\/a>.<\/p>\n

Remarkably, how the James Webb space telescope established this \u2013 a process known as transmission spectroscopy \u2013 is very similar, at least in principle, to the method which Fishacre employed. It detected subtle variations in the brightness and colour of the light emitted by TOI-421 b which could only be caused by water and sulphur dioxide.<\/p>\n

Given how much criticism his claims received, Fishacre would no doubt have been delighted to know that nearly 800 years after his death, contemporary astronomy, just like him, is using light and colour to show that far flung stars and planets are all made from the same elements.<\/p>\n

\"\"<\/p>\n

Looking for something good? Cut through the noise with a carefully curated selection of the latest releases, live events and exhibitions, straight to your inbox every fortnight, on Fridays. Sign up here<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"During the 1240s, Richard Fishacre, a Dominican friar at Oxford University, used his knowledge of light and colour…\n","protected":false},"author":2,"featured_media":250374,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":{"0":"post-250373","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/250373","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=250373"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/250373\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/250374"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=250373"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=250373"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=250373"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}