... Galileo Demonstrates the Telescope . ... Upon hearing at age 40 that a Dutch optician had invented a glass that made distant objects appear larger, Galileo crafted his own telescope and turned it toward the sky. ... As the Earth spins on its axis, the sky seems to rotate around us. ... Help Map The Moon . ... Crater Copernicus . ... Copernicus is a large young crater visible with binoculars slightly northwest of the center of the Moon's Earth-facing hemisphere. ... A Cluster Too Far . ...