Christopher M. Graney

About Christopher M. Graney

Christopher M. Graney is professor of physics and astronomy at Jefferson Community & Technical College in Louisville, Kentucky (USA), where he helps keep the college’s observatory running. For some years now his research focus has been the history of astronomy, especially the late 16th and early 17th centuries. He is the author of the 2015 book Setting Aside All Authority: Giovanni Battista Riccioli and the Science Against Copernicus in the Age of Galileo, published by the University of Notre Dame Press.

Strange Tales of Galileo and Proving: Omitted Data and the Tides
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Last week I wrote a post on how even books for children and travel books state (incorrectly) that Galileo proved that the Earth circles the sun, as Copernicus had said it did.  This post tells a strange story about Galileo’s efforts to prove that the Earth circles the sun. In Galileo’s time, no telescopic observation was likely to prove Earth’s motion.  Before the telescope had even been invented, Tycho Brahe had proposed a geocentric theory in which the planets circled the sun while the sun, moon, and stars circled the Earth.  Brahe’s theory was mathematically and observationally identical to Copernicus’s heliocentric theory insofar as the Earth, sun, moon, and planets were concerned: the “machinery” of both systems was the same, it was just that in Brahe’s the Earth stood still, whereas in Copernicus’s the sun stood still.  Galileo’s telescopic observations proved that Venus circled the sun—but Venus circled the sun in both Brahe’s geocentric theory and in Copernicus’s heliocentric theory.  … Continue reading

Punished for Proving
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History of astronomy turns up in unexpected places.  Unfortunately that history is often poorly presented.  Consider this example, found in a children’s book called C is for Ciao: An Italy Alphabet by Elissa D. Grodin and Governor Mario Cuomo: G is for Galileo, punished when he proved that the sun was sitting still and the earth’s the one that moved On the same page is— Until the Polish astronomer Nicolas Copernicus discovered that the sun is the center of our solar system… people since the second century had thought the sun revolved around the earth. —and— In developing the telescope, Galileo was able to prove that Copernicus’s theory was correct.  This caused a problem with church leaders of the day, who—disrespectful of scientific facts—were offended by the idea that the earth was not the center of the solar system. But Copernicus did not discover that the sun is the center—he hypothesized that it was.  Galileo did not prove that the … Continue reading

Copernicus’s On the Revolutions—A Book That Continues to Challenge
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Last week’s post featured old science books from the William Marshall Bullitt Collection in the Archives and Special Collections (ASC) of the Ekstrom Library of the University of Louisville here in Kentucky, and readers of this blog may recall an earlier post about the collection, too.  I currently have the enjoyable task of studying the books in the collection and writing discussions of them for the ASC—discussions specifically intended for a diverse audience that might include scholars, students at varying levels, and interested members of the general public.  One of the books in the collection that no doubt would interest readers of this blog (and that readers can go to see and study at the University of Louisville) is Nicolas Copernicus’s 1543 De Revolutionibus Orbium Cœlestium, or On the Revolutions of Heavenly Spheres.  This post is an adaptation (with permission) of the discussion I wrote for the ASC. De Revolutionibus is a book that challenged scientists and non-scientists alike when it … Continue reading

Another Post About Old Science Books? Well, they’re cool!
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If you like astronomy’s history then the University of Louisville (UofL) in Louisville, Kentucky, was a good place to be this past November 5th.  On that day the Kentucky Academy of Science was holding its 102nd annual meeting.  To go along with that meeting, the Archives and Special Collections of UofL exhibited a selection of books from its William Marshall Bullitt collection of rare works in mathematics and astronomy (which happens to be featured in a recent V.O. video).  Prof. Delinda Buie of UofL and I were on hand to talk to KAS attendees.  Almost all the attendees were scientists who work in Kentucky.  Many of them were seeing these historic works of science for the first time, and were absolutely enjoying themselves. Below is a small collection of photographs that I took during the exhibit.  Enjoy.  You can’t have too much of this stuff. … Continue reading

Vatican Observatory astronomers getting research published
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This is the blog of the Vatican Observatory.* V.O. director Guy Consolmagno is the Blog Boss. Most of the posts here are intended for an audience that is interested in science and has basic scientific literacy; the posts are generally not for conveying to working astronomers the latest research to come out of the V.O. But maybe it would be a good idea from time to time to highlight the latest V.O. research, because the V.O.’s astronomers are publishing stuff in the astronomical journals, and thus contributing to the body of scientific knowledge. So, here are some recent publications from V.O. astronomers with whom I have some direct connection.  At a later date I will do a post featuring publications by other V.O. astronomers. Guy Consolmagno, V.O. Director and El Jefe del Blog for The Catholic Astronomer! “Olivine on Vesta as exogenous contaminants brought by impacts: Constraints from modeling Vesta’s collisional history and from impact simulations,” by D. Turrini, V. … Continue reading

Sweltering Heat, Bitter Cold, Torrential Rain, Historic Floods: Why your friends, your family members, your co-workers, members of your church, your elected officials, and perhaps you yourself might be skeptical regarding Climate Change
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I study the seventeenth-century debate over the Copernican Theory, especially the scientific arguments of the anti-Copernican side in that debate.  It turns out that the anti-Copernicans, who are often portrayed as a bunch of anti-science numbskulls, had solid scientific reasons for what they thought.  Through my research I have come to a positive view of many of the anti-Copernicans, while of course still holding to my scientific views about the Earth circling the sun. Perhaps because of my familiarity with this story, I began some time ago to think about people who do not accept the scientific consensus regarding climate change.  Why do people not accept what the scientific community is telling them?  As a scientist, I can have a bad attitude toward such people—but then again, for most of my scientific career I had a bad attitude toward anti-Copericans, too.  I did some studying, checked my attitude, and in fact grew a pretty positive view of many climate change … Continue reading

Bored at the Speed of Light
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A proper “to-scale” representation of the solar system is hard to make. This is because the distances within the solar system are vast, compared to the sizes of the sun and the planets, and because there is so much variation in size among the sun and the planets themselves. Thus representations of the solar system inevitably show everything too close together, and too similar in size. But recently I was introduced to a nice online effort at a “to-scale” representation or model of the solar system — click here to have a look at it. “Thank you” to Fr. Joseph-Mary Hertzog, O.P., who introduced me to this model. The scale of this model is such that, on a modestly large screen, the moon is a single pixel in size, while the sun is roughly the size of an orange. The distances between planets is so great that an effort to manually scroll through this model from one planet to another … Continue reading

Astronomy in Art & Architecture: Minneapolis, Minnesota, USA
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Blogging for “The Catholic Astronomer” has prompted me to keep my eye and camera out for instances of math and science (and astronomy in particular) appearing in public art and architecture, because that seems like great subject matter for the blog.  Instances of public math and science (by this I mean something more than generic stars on the ceiling of a building) are rarer than I was expecting when I first got the idea to blog about them.*  However, as noted in a previous post, I found some in Milwaukee, Wisconsin.  And, in November I found this interesting objet d’art in Minneapolis, Minnesota: It is titled “Prophecy of the Ancients,” a 1988 work by Brower Hatcher.  According to the Walker Arts Center in Minneapolis, In his stone and steel-mesh sculpture…, [Hatcher] melds the logic of an engineer with a visionary’s impulse to transcend time and space.  A futuristic dome, composed of thousands of flexible wire polyhedrons, rests atop six mock-Egyptian … Continue reading

Biblical Signs in the Sky? September 23, 2017
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One day last fall I was working in my office when my desk phone rang.  It was a reader of The Catholic Astronomer, calling me with a question.  He asked why the Vatican Observatory blog was full of discussion on black holes or whatnot, when there was something much more momentous to talk about. It turns out that the momentous thing to which my caller was referring was an arrangement of celestial bodies that will occur this year (2017) on September 23.  On that date, according to various Internet sources, the heavens themselves will be a tableau of Revelation 12: A great sign appeared in the sky, a woman clothed with the sun, with the moon under her feet, and on her head a crown of twelve stars.  She was with child and wailed aloud in pain as she labored to give birth.…  She gave birth to a son, a male child, destined to rule all the nations with an … Continue reading

Monsignor Bouchet’s Telescope
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Astronomy pops up in unexpected places.  Consider, for example, this fantastic old refracting telescope: This telescope has an aperture of roughly 4 inches (10 centimeters).  The tube appears to be brass.  The telescope has a very stout wooden case, visible in the picture above.  The picture below gives another view of the telescope, the case (now open), and an eyepiece for the telescope (lying to the left of the telescope). By now you have probably noticed the telescope’s surroundings, namely the monstrances and crucifix on display in the background.  Why is an old telescope sitting on a table, surrounded by religious articles?  Because this is the telescope of Monsignor Michael Bouchet (1827 to 1903), former vicar-general of the Diocese of Louisville, Kentucky.  It is housed within the Bishop Benedict Joseph Flaget Library, which itself is part of the Archdiocesan History Center of Louisville’s Cathedral of the Assumption.  Tim Tomes, a parishioner at the Cathedral who does a lot of work … Continue reading

The Solstice and the Daylight in Charleston and Santiago: Part IV — Early January
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This is the final entry in a four-part series of posts on daylight and the December 21 solstice.  The first was on the “darkest evening”/“brightest morning” of the year.  The second was on the solstice itself.  The third was on perihelion.  And now we have reached the last daylight-and-the-solstice milestone: the “darkest morning” of the year for the northern hemisphere, and the “brightest evening” of the year for the southern hemisphere. In the northern hemisphere the mornings are darkest now, in early January; now is when the latest sunrise occurs.  Likewise, in the southern hemisphere the latest sunset, and thus the brightest evening, occurs now.  As discussed in the previous post, this is because the earth is near perihelion in its orbit.  Its orbital motion is faster than usual, causing the period of daylight to drift backwards (that is, later) against the clock, brightening the evenings and darkening the mornings. Between when the solstice occurred and now this perihelion drift had … Continue reading

The Solstice and the Daylight in Charleston and Santiago: Part III — Perihelion Day!
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Today is Perihelion Day!  If you have a 2017 Vatican Observatory calendar you will see this marked on that calendar for January 4.  The Earth journeys around the sun in an orbit that is ever-so-slightly elliptical (the elliptical nature of the orbit is so mild that the orbit basically looks like a circle that is slightly off-center from the sun).  This means that the distance between the sun and the Earth varies over the course of a year.  Today is the day on which that distance is a minimum, and the technical term for the point of minimum distance between the Earth and sun is “perihelion.” Today is also the day of the “Super Sun” (to borrow the language of the “Super Moon” hoopla of this past fall) because since the distance to the sun is a minimum then the apparent size of the sun in the sky is a maximum (of course, as with the “Super Moon,” this effect … Continue reading