Robotic spacecraft have done an amazing job of expanding human understanding of the worlds of the solar system, and few have done more to aid the cause than the Cassini probe that has been orbiting Saturn since June 30, 2004. Among its astonishing discoveries: lakes of frozen natural gas on Titan, icy geysers on Enceladus, and bizarre hexagonal storms circling Saturn’s north pole. DISCOVER recently featured a guided tour of Cassini pictures, curated by the mission’s top imaging expert, Carolyn Porco.
But humanity’s far-flung emissaries have not just explored other worlds; they have also provided new perspectives on our place in space, by staring across the vast geometry of our entire solar system. The latest example of this stunning achievement: A new image of Venus taken from Saturn.
The scene here is so unfamiliar that it requires a little decoding. At the moment of this snapshot, Cassini is located behind the night side of Saturn, looking back roughly toward the sun (the only way it can see Venus, since Venus is much closer to the sun than Saturn is). Most of Saturn is almost dark, lit only dimly by reflected light from the rings, except for a thin bright crescent at left. The rings appear odd because they are back-lit, seen only by scattered sunlight. And that one bright dot? That is Venus, reflecting sunshine off its brilliant white clouds, seen from roughly 900 million miles away.
The new Cassini image joins other stunning view of worlds from other worlds, including Earth and Jupiter together from Mars, Earth from Mars during sunset, a beautiful earlier Cassini shot showing Earth as a “blue dot” behind Saturn’s rings, and the original “pale blue dot” view of Earth seen from Voyager 4 billion miles away, at the edge of the solar system–a look back across the entire realm of the planets.