On 7 January 1610, Galileo observed with his telescope what he described at the time as "three fixed stars, totally invisible by their smallness", all close to Jupiter, and lying on a straight line through it.
La 7 ianuarie 1610, Galileo a observat cu telescopul său ceea ce era descris la acea vreme ca „trei stele fixe, totalmente invizible prin micimea lor”, toate apropiate de Jupiter, aflate pe o linie dreaptă cu acesta.