Saturn and His Anses

Helden, Albert Van

doi:10.1177/002182867400500204

Cited by 73 publications

(19 citation statements)

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“…Most observers thought that Saturn's features were due to satellites, and that is what they reported seeing when they observed Saturn. However, other astronomers believed that Saturn had a ring, and they reported seeing a ring when they observed Saturn (Helden, 1974). But it seems to us that no one who views one of the unambiguous photographs taken by one of the Voyager spacecraft could possibly doubt that Saturn is encircled by a ring.…”

Section: Characteristic 2 Ambiguity Of the Datamentioning

confidence: 99%

The Role of Anomalous Data in Knowledge Acquisition: A Theoretical Framework and Implications for Science Instruction

Chinn

Brewer

1993

Review of Educational Research

342

420

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Understanding how science students respond to anomalous data is essential to understanding knowledge acquisition in science classrooms. In this report, we present a detailed analysis of the ways in which scientists and science students respond to anomalous data. We postulate that there are seven distinct forms of response to anomalous data, only one of which is to accept the data and change theories. The other six responses involve discounting the data in various ways in order to protect the preinstructional theory. We analyze the factors that influence which of these seven forms of response a scientist or student will choose, giving special attention to the factors that make theory change more likely. Finally, we discuss the implications of our framework for science instruction.Anomalous Data -2 THE ROLE OF ANOMALOUS DATA IN KNOWLEDGE ACQUISITION: A THEORETICAL FRAMEWORK AND IMPLICATIONS FOR SCIENCE INSTRUCTIONThis report addresses an issue that is crucial for understanding how people learn science and how to improve science instruction: How do students respond when they encounter scientific information that contradicts their current theories' about the physical world? In other words, how do students respond when their current beliefs about the physical world conflict with the information presented during science instruction?This issue is crucial for two reasons. The first is that encountering contradictory information is a very common occurrence when one is learning science. Science students' preinstructional beliefs about the natural world often conflict sharply with many of the accepted scientific theories they are taught in school, and this is true across a wide variety of domains within biology, chemistry, and physics (for reviews, see Carey, 1985;Champagne, Klopfer, & Gunstone, 1982;Confrey, 1990;Driver & Easley, 1978; Driver, Guesne, & Tiberghien, 1985;Eylon & Linn, 1988;Osborne & Freyberg, 1985;Perkins & Simmons, 1988;Roth, 1990). Thus, the encounter with contradictory information is at the heart of knowledge acquisition in science.The second reason why understanding how students respond to contradictory information is crucial for science education is that students typically resist giving up their preinstructional beliefs. Instead of abandoning or modifying their preinstructional beliefs in the face of new, conflicting data and ideas, students often staunchly maintain old ideas and reject or distort new ideas. For instance, some children who are told that the earth is round preserve their preinstructional belief that the earth is flat by concluding that the earth is disc shaped (Vosniadou & Brewer, 1992). Similarly, children can spend days or weeks studying photosynthesis and yet persist in their preinstructional belief that plants get their food from the soil (Anderson & Smith, 1984). And a number of researchers have found that many young adults go through high school and university physics courses without ever giving up their pre-Newtonian views of motion (e.g., Champagne, Klopfer, & Anderson...

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Section: Characteristic 2 Ambiguity Of the Datamentioning

confidence: 99%

The Role of Anomalous Data in Knowledge Acquisition: A Theoretical Framework and Implications for Science Instruction

Chinn

Brewer

1993

Review of Educational Research

342

420

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“…9 A newsletter printed in The Hague early in October was sent to the major European cities in diplomatic pouches, 10 and a French soldier departed from The Hague for Paris with knowledge of how to make spyglasses. 11 In November, the newsletter was received by Paolo Sarpi, who shared its content with Galileo. 12 We can get some idea of what Galileo's first, three-powered spyglass looked like from a sketch made in August 1609 of the first actual spyglass to arrive in Naples, by the internationally known polymath, Giambaptista della Porta (Fig.…”

Section: Galileo's Telescopementioning

confidence: 99%

“…In his third sunspot letter, printed in 1613, Galileo reported that since there had been no change in the positions of Saturn's "companions," he had lost interest, but that when he happened to look at the planet again in 1612 he was surprised to see the appendages gone. Had Saturn devoured his children [11]? Since Saturn's appearance was neutral in the debate between the world systems, the problem was only occasionally discussed until the 1640s, when a new generation of telescopic observers usually armed with better telescopes took on the problem.…”

Section: The Long Refractor and Further Discoveriesmentioning

confidence: 99%

The beginnings, from Lipperhey to Huygens and Cassini

Helden

2009

Exp Astron

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The first century of telescopic astronomy can be divided into two periods. During the first, from 1609 to ca. 1640, observations were made with a simple "Dutch" or "Galilean" telescope with a concave eyepiece. Galileo made all his discoveries with this instrument. Its limited field of view, however, made magnifications of more than about 20 impractical, and therefore this instrument's limit had been reached within a few years. During the second period, ca. 1640-ca. 1700, the simple astronomical telescope came into use, almost immediately augmented with a field lens and an erector lens (the latter used only for terrestrial purposes). Magnifications were increased by increasing the focal lengths of objectives, and this quickly led to very long telescopes, often used without a tube. The astronomical discoveries made possible by this form of the instrument were, however, made with instruments of relatively modest lengths. By the end of the century, very long telescopes fell out of use, while shorter ones were adapted for measurements. Further discoveries became possible only with the reflecting telescope in the second half of the eighteenth century.

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“…When human perception is at its limits, even basic observations are unreliable, and may be biased towards what the observer expects to see. Van Helden surveyed the history of early telescopic observations of Saturn 8 . While most observers today, even with very low-resolution pictures, see a planet with rings, early observers echoed Galileo's first observations, and saw and reported on a planet with two giant moons, one on each side.…”

Section: Observationsmentioning

confidence: 99%