Mathieu Ossendrijver of Humboldt University in Berlin found the tablet while combing through the collections at the British Museum. The written record gives instructions for estimating the area under a curve by finding the area of trapezoids drawn underneath. Using those calculations, the tablet shows how to find the distance Jupiter has traveled in a given interval of time. Until now, this kind of use of trapezoids wasn't known to exist before the 14th century. ... By 400 B.C. Babylonian astronomers had worked out a coordinate system using the ecliptic, the region of the sky the sun and planets move...