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Consider a short-period comet (specifically, Comet Encke). Pros: Very short-period comets can have orbital periods of only a few years, with approaches relatively close to Earth ($\sim0.1\text{ ...
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2020-06-01T14:13:52Z (over 4 years ago)
Source: https://worldbuilding.stackexchange.com/a/74447 License name: CC BY-SA 3.0 License URL: https://creativecommons.org/licenses/by-sa/3.0/