Titlebook: Visually Observing Comets; David A. J. Seargent Book 2017 Springer International Publishing Switzerland 2017 Amateur comet-hunting.How to

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Visual Comet Huntingover 5 years have passed since the latest visual discovery of a comet. This is strikingly different from the situation prior to about 1995. Back then, it was a rare year that did not bring forth several comets discovered by amateur astronomers systematically sweeping the skies with wide-field telesc

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Observing Known Cometser. Each year brings its stock of returning periodic and newly discovered non-periodic comets, and most of the time there will be some “known” comet within the visual range of small or moderately sized telescopes. To some, the routine observation of a dim comet might appear dull fare, but it is prec

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The Coma: How to Estimate Its Brightness and Record Its Featurest-period comets is essential in determining changes that may occur over time, and contemporary visual observation is the only safe way of comparing the brightness of a periodic comet as it appears today with the observations of yesteryear. Moreover, brightness estimates of long-period comets tell us

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29P/Schwassmann-Wachmann, an “Outbursting” Comet to Watchunusual happens!), but because it moves in an almost circular orbit between the giant outer planets Jupiter and Saturn it is, like these planets, accessible every year throughout its orbit. Most of the time, it will appear as nothing more than a speck of light between magnitudes 17 and 18, out of th

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Some Prominent Visual Comet Discoverersen to that object and will remain in the catalogs of cometary apparitions long after the comet itself has faded from view. These ambitions have drawn astronomers to the gentle sport of visual comet hunting for over two centuries, and happily, despite the growth of automated sky patrols using relativ

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Observing Known Cometsdow through which their physical nature may be glimpsed. It is also through regular estimates of a comet’s brightness and general appearance that any unexpected departure from its regular behavior (a sudden brightening or fading, for example) becomes apparent and may give clues as to the future development of the comet in question.

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