more at scitech.quickfound.net "Presents three parts on comets. Reveals that comets were born with the sun some 4.5 billion years ago but, unlike planets, the primitive ice and dust of coments have remained unchanged. Shows that they are windows into time, into the origins of the solar system. Defines comets and gives a historical account of them, including Halley's comet in Part One. Looks at new studies investigating comets at short range, presently only from observations on Earth, but new space probes will allow the close-up study of comets." Public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. en.wikipedia.org A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma (a thin, fuzzy, temporary atmosphere) and sometimes also a tail. The! se phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. Comets have been observed since ancient times and have traditionally been considered bad omens. Comets have a wide range of orbital periods, ranging from a few years to hundreds of thousands of years. Short-period comets originate in the Kuiper
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