In 1781, German-born British astronomer William Herschel made Uranus the first planet discovered with the aid of a telescope. This frigid planet, our solar system's third largest, remains a bit of an enigma 243 years later. And some of what we thought we knew about it turns out to be off the mark.

Much of the knowledge about Uranus was gleaned when NASA's robotic spacecraft Voyager 2 conducted a five-day flyby in 1986. But scientists have now discovered that the probe visited at a time of unusual conditions — an intense solar wind event — that led to misleading observations about Uranus, and specifically its magnetic field.

Solar wind is a high-speed flow of charged particles emanating from the sun.