About 7.4 light-years from the Sun, a dim ball of gas about as wide as Jupiter drifts through space with no star to warm it. Jupiter is large enough to fit some 11 Earths side by side. (A light-year is the distance light travels in a year, nearly 6 trillion miles.) That puts the object […]

In 1787, Catherine the Great set off on a six-month tour of Crimea, a territory Russia had annexed only four years earlier. The emperor of Austria and a group of European diplomats travelled with her. Along the route, triumphal arches had been built specially for the occasion, and the inscription they carried was hard to […]