1846: The French astronomer Urbain Le Verrier presents his definitive calculations to the Academy of Sciences, predicting the existence and position of an eighth planet. This planet was responsible for unexplained perturbations in the orbit of Uranus. On the following 23 September, the astronomer Johann Galle observed Neptune at the exact spot indicated by Le Verrier (within less than one degree). This achievement, described as a "discovery at the tip of a pen," masterfully confirmed the validity of Newton's law of universal gravitation.

1911: A magnitude 4.2 (ML) earthquake strikes the region of Ransart (Charleroi, Hainaut). With an intensity of VI, this earthquake was the first major damaging event documented in the coal basin. Chimneys were toppled and cracks appeared in numerous buildings, with the tremors felt as far away as Brussels. Monitored by the Royal Observatory of Belgium, this event sits within the complex tectonic context of the Sambre-et-Meuse furrow, serving as a reminder that human activity (mining) sometimes takes place over natural fault zones ready to rupture.

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