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Observatio & demonstratio cometae aetherei, qui anno 1577 et 1578 constitutus in sphaera veneris, apparvit, cum admirandis eius passionibus, varietate scilicet motus, loco, orbe, distantia à terrae centro, &c. adhibitis demonstrationibus geometricis & calculo arithmetico, cuiusmodi de alio quoquam cometa nunquam visa est
No prior complete English translation of this text has been found.
Extensive searches across scholarly catalogs (UNESCO Index Translationum, Brill, etc.), Google Books, and Open Library for Michael Mästlin's 1578 Latin work on the comet of 1577 yielded no results for an English translation. While Mästlin is a significant figure in the history of astronomy, this specific technical treatise appears to remain untranslated in full into English.
Verified Mar 15, 2026 via local catalogs, local catalogs, ustc, google books, open library · methodology
In 1577, a comet streaked across the sky and defied the rigid laws of the ancient world. Michael Mästlin proves that this visitor was no atmospheric vapor, but a celestial traveler moving through the sphere of Venus according to the math of the Copernican universe.