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Seneca on Comets and Ancient Cometary Theory

Gareth Williams

in The Cosmic Viewpoint: A Study of Seneca's Natural Questions

In Natural Questions 7, on comets, Seneca departs from the influential Aristotelian view that comets are sublunary occurrences. In arguing that they are supralunary, he identifies them as planetary ... More

In Natural Questions 7, on comets, Seneca departs from the influential Aristotelian view that comets are sublunary occurrences. In arguing that they are supralunary, he identifies them as planetary phenomena that follow regular but unknown orbits. In reviewing different theories that culminate in this supralunary interpretation, he progresses from the atmospheric to a ‘higher’, celestial mode of theorizing - an ascent which is also symbolic, raising us to a form of celestial insight that is far removed from ‘lower’ forms of cometary conjecture. Late in the book Seneca laments the apparent decline of interest in philosophy in his contemporary Rome; but this very book, in its upward movement towards the celestial view of comets, offers a powerful countermand to that depressing picture, as if liberating the investigative instinct to reach forth beyond conventional limits of thought.Less

Lorenzo Bonincontri’s reception of Manilius’ chapter on comets (Astr. 1.809–926)

Stephan Heilen

in Forgotten Stars: Rediscovering Manilius' Astronomica

This comparison of Bonincontri’s De rebus naturalibus et divinis I.1.474-591 with Astr. 1.809-926 includes Bonincontri’s respective commentaries on both poems. While our humanist imitated Manilius at ... More

This comparison of Bonincontri’s De rebus naturalibus et divinis I.1.474-591 with Astr. 1.809-926 includes Bonincontri’s respective commentaries on both poems. While our humanist imitated Manilius at multiple levels, there are also differen­ces regarding the autobio­graphical dimension of his chapter on comets and the way how he incorporated Manilius’ doxography of ancient explanations of their origin and significance (1.817-75) into his own world view, giving one inconspicuous Hermetic element (Astr. 1.874-5) prominence in his own Christian version. Structural analysis indicates that Bonincontri originally treated only the comet of 1456 and added lines 547-52 and 588-91 later, after the appearance of the comet of 1472. The appendix contains Bonincontri’s Latin passage with a line-by-line commentary, which draws on various early modern sources and on up-to-date technical data such as the orbital parameters of the comets of 1456 and 1472 and the seismological assessment of the Neapolitan earthquake of 1456.Less

Celestial portents and apocalypticism in medieval Ireland

Mark Williams

in Fiery Shapes: Celestial Portents and Astrology in Ireland and Wales 700–1700

This chapter deals with Ireland from the 7th to the 12th centuries, which represents the oldest literary material from the medieval Celtic world. It shows that a conspicuously biblical paradigm for ... More

This chapter deals with Ireland from the 7th to the 12th centuries, which represents the oldest literary material from the medieval Celtic world. It shows that a conspicuously biblical paradigm for celestial portents held in the period. Churchmen recorded astronomical events throughout the early Middle Ages in the voluminous Irish annals, but their descriptions are coloured by the lurid apocalypticism characteristic of the early medieval Church. Thus comets and eclipses, for example, are transformed into ominous portents of Doomsday. The chapter then shows that this apocalyptic framework lies behind the depiction of heavenly portents in secular literature.Less

Ice in nature

Victor F. Petrenko and Robert W. Whitworth

in Physics of Ice

This chapter surveys the many forms in which ice occur in nature. Lake and river ice have characteristic polycrystalline structures and these are different from sea ice. In the atmosphere water ... More

This chapter surveys the many forms in which ice occur in nature. Lake and river ice have characteristic polycrystalline structures and these are different from sea ice. In the atmosphere water vapour crystallizes to form snowflakes and leads to rain, hail and thunderstorm electricity. Snow falling on the ground has specific properties and over many years it becomes consolidated into ice. Such ice flows under gravity eventually melting into rivers or the oceans. Cores drilled from ice sheets in Antarctica or Greenland contain information about past climatic conditions, and their study depends heavily on the electrical properties of ice. In cold regions ground becomes frozen to form permafrost. In the Solar System many of the moons of the outer planets are formed from ice, which may exist as some of the high-pressure phases in the interior. The surface features of Europa are particularly intriguing. Finally comets are largely composed of ice.Less

Macrocosm to Microcosm: Reading the Skies and Stars in Fatimid Egypt

Yossef Rapoport and Emilie Savage-Smith

in Lost Maps of the Caliphs: Drawing the World in Eleventh-Century Cairo

The anonymous author of the Book of Curiosities provides an account of the origins of astronomy and astronomical tables, placing it in the Indian city of Kannauj. This tale merges the biography of ... More

The anonymous author of the Book of Curiosities provides an account of the origins of astronomy and astronomical tables, placing it in the Indian city of Kannauj. This tale merges the biography of Gautama Buddha with the origins of the Indian manual of astronomy known as the Sindhind. The author then records, and illustrates, four different ways of mapping portions of the sky, including schemes inherited from classical Greek astronomers such as Ptolemy that involved the forty-eight classical constellations of the sky, many of which are familiar to readers today. They include also mapping schemes derived from a Late-Antique tradition attributed to the legendary Egyptian-Greek sage known as Hermes Trismegistus, another reflecting pre-Islamic Bedouin customs, and yet another system (known as ‘lunar mansions’) ultimately derived from Central Asia or India. The author devotes illustrated chapters to comets and meteors (‘stars with tails’), again using different sources for his information, some ascribed to Ptolemy, others taken from the Hermetic tradition. Stars, planets and comets were all seen as indicative of future events on Earth. The final chapter of the first part of the Book of Curiosities is on winds, lightning, thunder, and earthquakes, and what they might portend.Less

Planetary Order, Astronomical Reform, and the Extraordinary Course of Nature

Robert S. Westman

in The Copernican Question: Prognostication, Skepticism, and Celestial Order

Attention to the science of astronomy, already so well sustained in the Wittenberg cultural sphere, received an unexpected boost with the dramatic and unheralded arrival of two apparitions in the ... More

Attention to the science of astronomy, already so well sustained in the Wittenberg cultural sphere, received an unexpected boost with the dramatic and unheralded arrival of two apparitions in the skies of the 1570s. One was a brilliant entity—represented variously as a meteor, a comet, or a new star—that appeared in 1572 and remained until May 1574. The other—represented almost universally as a “bearded star” or comet—could be seen for just over two months between November 1577 and January 1578. This chapter explores planetary order, astronomical reform, and the extraordinary course of nature. It discusses astronomical reform and the interpretation of celestial signs, Thaddeus Hagecius's polemic on the new star, Tycho Brahe and his Copenhagen oration, Brahe's relationship with Giovanni Pico della Mirandola, Valentine Naibod's circumsolar ordering of Mercury and Venus, astrological and eschatological meanings of comets, and the language and syntax of cometary observation. Finally, the chapter considers the views of Maestlin, Brahe, Cornelius Gemma Frisius, and Helisaeus Roeslin regarding place and order, the comet, and the cosmos.Less

Mary Proctor (1862–1957)

Daniel R. Altschuler and Fernando J. Ballesteros

in The Women of the Moon: Tales of Science, Love, Sorrow, and Courage

This chapter describes the figure of Mary Proctor, American popularizer of astronomy, and her work to make science understandable.

Impending Disaster

Evelyn Lord

in The Great Plague: A People's History

The year 1665 began with winter and there was great snow and frost. Following the thaw in March, there was no rain and by April, there was a threat of drought. As the heat of the summer grew, ... More

The year 1665 began with winter and there was great snow and frost. Following the thaw in March, there was no rain and by April, there was a threat of drought. As the heat of the summer grew, apprehension and anxiety about the plague led to panic in Cambridge. It was expected, as people believed that the appearance of a comet in April and the exceptionally cold weather were all signs of an impending disaster.Less

Science and the Solar System Over Easy

Neil F. Comins

in The Traveler's Guide to Space: For One-Way Settlers and Round-Trip Tourists

This chapter defines some essential terms, such as "space" and paints the big picture of our neighborhood of space, what is in our astronomical neighborhood, and what places in it we will be able to ... More

This chapter defines some essential terms, such as "space" and paints the big picture of our neighborhood of space, what is in our astronomical neighborhood, and what places in it we will be able to visit in the near future. It also presents the basic physics, such as the different types of electromagnetic radiations, necessary to understand some of the issues surrounding space travel, such as radiation hazards and weightlessness.Less

Training for Space Travel

Neil F. Comins

in The Traveler's Guide to Space: For One-Way Settlers and Round-Trip Tourists

Chapter 4 discusses training for extreme acceleration and, conversely, for microgravity. Trains travelers on how to deal with emergency situations. Examines everyday situations like going to the ... More

Chapter 4 discusses training for extreme acceleration and, conversely, for microgravity. Trains travelers on how to deal with emergency situations. Examines everyday situations like going to the bathroom in space.Less

Experiences by Destination

Neil F. Comins

in The Traveler's Guide to Space: For One-Way Settlers and Round-Trip Tourists

Using a variety of pictures taken on the Moon, on Mars, and on nearby asteroids and comets, this chapter explores a variety of locations that space tourists might find especially interesting.

The Freedom of Intellect

Roger Wagner and Andrew Briggs

in The Penultimate Curiosity: How Science Swims in the Slipstream of Ultimate Questions

This chapter focusses on Galileo’s The Assayer, his contribution to a debate that began with the appearance in August 1618 of the first of three comets. These had been observed by the Jesuits of the ... More

This chapter focusses on Galileo’s The Assayer, his contribution to a debate that began with the appearance in August 1618 of the first of three comets. These had been observed by the Jesuits of the Collegio Romano using their Galilean telescope. Orazio Grassi, the professor of mathematics at the college, published a report arguing that the comet was located between the Moon and the Sun, supporting this with arguments that included the suggestion that the more distant an object, the less it was magnified by a telescope. Galileo responded to this publication with The Assayer, which reads almost as a manifesto of his approach to natural philosophy. Although barred from directly advocating Copernicus’ system, Galileo sought to ‘teach a method which would inevitably transform all natural philosophy and thus sooner or later establish a true system of the universe and demolish Aristotelian physics’.Less

“I Resolved to Throw Aside All Manner of Hypotheses … and to Attend Wholly to What the Appearances Themselves Would Teach Me”

Matthew C. Hunter

in Wicked Intelligence: Visual Art and the Science of Experiment in Restoration London

Micrographia (1665) is not only Robert Hooke’s most famous work; it was a totemic project for the early Royal Society of London. Published when its author was not yet thirty years old, Micrographia ... More

Micrographia (1665) is not only Robert Hooke’s most famous work; it was a totemic project for the early Royal Society of London. Published when its author was not yet thirty years old, Micrographia manifests the pronounced influence of lessons Hooke had learned in the painting studio of Peter Lely and from collaborative work with Oxford’s experimental-philosophical elites. Yet, as this chapter argues, the confident pictorial strategies and robust epistemological value that Hooke theorized for Micrographia’s stunning images also depart massively from the fragmentary, tortured visual forms of his later draftsmanship, particularly his astronomical drawings of the early 1680s. That late graphic work has been much less well known because it was actively suppressed by Hooke’s posthumous editor—this despite the fact that Hooke assigned it even stronger cognitive force than Micrographia’s plates. How do we account for these strange shifts and discrepancies between graphic form and cognitive function? Working between these paired groupings of drawings from the 1660s and 1680s, the chapter shows how Hooke’s weird pictorial project effectively explodes a sequence of carefully-crafted observational protocols and models of the experimental-philosophical self, as well as the narratives by which recent, interdisciplinary interpretation would bind them.Less

On the Possibilities of an Antiracist Racial Worldmaking

Mark C. Jerng

in Racial Worldmaking: The Power of Popular Fiction

This conclusion synthesizes the main analyses of the book and explores its implications for transforming our conventional ideas about the literary and historical foundations of race and racism. It ... More

This conclusion synthesizes the main analyses of the book and explores its implications for transforming our conventional ideas about the literary and historical foundations of race and racism. It then analyzes the work of W.E.B. DuBois for the way in which he navigates genre, race, and world in several of his works including Black Reconstruction, “The Comet,” and Worlds of Color. In DuBois, this conclusion finds the possibilities of an anti-racist racial worldmaking.Less

Griffith’s Equation: Fracture

Brian Cantor

in The Equations of Materials

Most materials fracture suddenly because they contain small internal and surface cracks, which propagate under an applied stress. Griffith’s equation shows how fracture strength depends inversely on ... More

Most materials fracture suddenly because they contain small internal and surface cracks, which propagate under an applied stress. Griffith’s equation shows how fracture strength depends inversely on the square root of the size of the largest crack. It was developed by Alan Griffith, while he was working as an engineer at Royal Aircraft Establishment Farnborough just after the First World War. This chapter examines brittle and ductile fracture, the concepts of fracture toughness, stress intensity factor and stBiographical Memoirs of Fellows ofrain energy release rate, the different fracture modes, and the use of fractography to understand the causes of fracture in broken components. The importance of fracture mechanics was recognised after the Second World War, following the disastrous failures of the Liberty ships from weld cracks, and the Comet airplanes from sharp window corner cracks. Griffith’s father was a larger-than-life buccaneering explorer, poet, journalist and science fiction writer, and Griffith lived an unconventional, peripatetic and impoverished early life. He became a senior engineer working for the UK Ministry of Defence and then Rolls-Royce Aeroengines, famously turning down Whittle’s first proposed jet engine just before the Second World War as unworkable because the engine material would melt, then playing a major role in jet engine development after the war, including engines for the first vertical take-off planes.Less

Reasoning among the Stars

Joan L. Richards

in Generations of Reason: A Family's Search for Meaning in Post-Newtonian England

In 1831, Francis Baily’s hopes realized when the Astronomical Society was elevated to Royal Astronomical Society (RAS). In the same year De Morgan became honorary secretary, and he, Richard ... More

In 1831, Francis Baily’s hopes realized when the Astronomical Society was elevated to Royal Astronomical Society (RAS). In the same year De Morgan became honorary secretary, and he, Richard Sheepshanks, and George Biddel Airy came together as an “equitanacious triangle” of reasoned mathematical astronomers. Sophia and Augustus first began to notice each other in the context of RAS parties at Baily’s house, in which wives and sisters lightened the intensity of the men’s interactions. In 1835, the return of Halley’s comet severely tried RAS claims for the power of their work. As they scrambled to trace its orbit, William Frend contributed his observations from the countryside while Sophia and the other women poked fun at the men with parlor plays. Conflicts about the nature of astronomy continued in the form of a protracted legal battle between Sir James South and Edward Troughton, the instrument maker he hired to mount and object glass. The equitenacious triangle worked to bring South down, while the women wrote parlor plays extolling their heroism.Less

Later years

I.S. Glass

in Nicolas-Louis De La Caille, Astronomer and Geodesist: South African Astronomical Observatory

La Caille returned to France via Mauritius and Reunion. He was received with acclaim at the Academy, where he gave several lectures on his Cape experiences. He published a map of the Cape which ... More

La Caille returned to France via Mauritius and Reunion. He was received with acclaim at the Academy, where he gave several lectures on his Cape experiences. He published a map of the Cape which remained the standard for over half a century. He became involved in controversies with Euler and later with Le Monnier. His most famous student was the chemist Lavoisier, who acknowledged the usefulness of La Caille's rigorous approach. He strongly influenced Lalande. Towards the end of his life, his friends included Clairaut, Bouguer and his correspondents Bradley and Tobias Mayer of Gottingen. He observed Comet Halley on its return and gave it its name. He died of an illness which was believed to have been contracted at the Cape.Less

Some Early Astronomy

David Clarke

in Reflections on the Astronomy of Glasgow: A story of some 500 years

The activities of the first local notable person related to Glasgow astronomy form this chapter. George Sinclair, Professor of Natural Philosophy, is known for his tracts on physics, astronomy, ... More

The activities of the first local notable person related to Glasgow astronomy form this chapter. George Sinclair, Professor of Natural Philosophy, is known for his tracts on physics, astronomy, mathematics, religion and witchcraft. His chief astronomical text of 1688 on the ‘Celestial Sphere’ was ‘The Principles of Astronomy and Navigation’. He was notoriously accused of plagiarism on several occasions, particularly in claiming authorship of ‘Truth's Victory over Error’, a religious text simply translated from a Latin script of Dickson of Edinburgh. He wrote on the principles of coal mining, but it was suggested that he was better at ‘mining the minds of others’ rather than writing with originality. He observed Newton's Comet of 1681 but was taken to task by Professor Gregory of St Andrews on the uselessness of his observations. Other astronomical studies related to the secular movements of the Sun and Moon were also castigated in similar vain. He had a passion for understanding the behaviour of the barometer according to the weather and was the first person, at least in Scotland, to measure the heights of mountains by barometric pressure changes on their summits. He is also credited with inventing the diving bell for undersea wreck salvaging.Less

The Height of the Verne Cycle, 1960–1962

Brain Taves

in Hollywood Presents Jules Verne: The Father of Science Fiction on Screen

The peak year of the Verne cycle was 1961, when four Hollywood Verne movies were released as well as several imports, along with television originals; never again would so many adaptations be ... More

The peak year of the Verne cycle was 1961, when four Hollywood Verne movies were released as well as several imports, along with television originals; never again would so many adaptations be produced in such rapid order. Verne filmmaking was about to move beyond spectacle and entertainment for the whole family to aim at younger filmgoers drawn by modestly budgeted but no less inventive science fiction; as one producer commented, Verne was as important a name as the biggest stars of the day. Some of these films, most notably Ray Harryhausen’s new version of The Mysterious Island, incorporated monsters reminiscent of those in Journey to the Center of the Earth (1959), while themes echoed Disney’s 20,000 Leagues under the Sea. This was apparent not only in the return of Captain Nemo in Mysterious Island but also especially in Master of the World, based on two Verne novels and scripted by science fiction writer Richard Matheson to transform the novels’ vague global threat into a highly topical disquisition on pacifism.Less