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This article deals with the study of aurora borealis carried out by Jean-Jacques Dortous de Mairan. Because of the fears generated by popular observations of northern lights in France in 1716, Mairan was commissioned by the Royal Academy of Sciences to give a rational explanation of the phenomenon. Unlike Edmond Halley, Mairan ascribed a major role to the Sun in the appearance of the aurora, and denied an electric or magnetic origin. During the 19th century, the cosmic theory of Mairan was discredited, for instance by François Arago and Alexander von Humboldt, who defended the atmospheric origin imagined by Halley. Finally, at the end of the 19th century, when aurora studies benefited from the recent discoveries of new radiations such as cathode rays, Mairan appeared as an important precursor of the new explanation of northern lights and the emergence of geophysics. We defend the idea that it was less the content of his theory than the historicity he gave to the aurora that enabled Mairan to construct this phenomenon as a scientific object, and thus remove it from the realm of marvels.