Science: Parting Shot

Four days and 3.3 million miles after its closest encounter with Saturn last month, the Voyager 1 spacecraft cast a last backward glance and transmitted this stunning portrait of the ringed giant. The photograph shows a crescent Saturn casting a shadow on its own rings, from the perspective a traveler might get by approaching from the stars, rather than from the interior reaches of the solar system. Re-created bit by electronic bit in computers at Caltech's Jet Propulsion Laboratory and released last week, the shot is so detailed that patches of the planet can be glimpsed through the rings, which are...