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Oort selects 46 comets to study and studies them thoroughly.
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Astronomers start thinking that the Oort cloud existed.
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Astronomer Jan Oort revives the theory of the Oort cloud as he explains that comets are destroyed after several passes through the inner Solar System, meaning that no more comets could be observed now.
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Astronomers start to realize that the Oort cloud could have an internal section that would start at about 448794000000 km from the Sun and continue up to approximately at 298719680000000 km.
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The main model of an "inner cloud" was proposed by an astronomer named astronomer J.G. Hills and named it 'Hill's cloud' after himself.
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Sidney Van Den Bergh and Mark E. Bailey suggested the Hills cloud's structure.
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Bailey states that the majority of comets in the Solar System were located not in the Oort cloud area, but closer and in the Hills cloud, with an orbit with a axis of 247989353500 km.
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Bailey's research was further investigated upon by studies of Victor Clube and Bill Napier.