The moon has always had a rough ride. Incapable of generating light itself, the moon’s glory is, at best, a reflected splendour – pale in comparison to that solar superstar, the sun, that outshines it. Though many poets have been drawn to the moon’s lyrical illuminations (Samuel Taylor Coleridge and William Butler Yeats were especially bewitched by its nocturnal power) some, such as Percy Bysshe Shelley, have pitied the fate to which the lonesome orb is galactically doomed: “Wandering companionless / Among the stars … like a joyless eye”. Nor has the moon always fared much better in the eyes of philosophers. “You see in the moon”, the 20th-Century British logician Bertrand Russell once observed, “the sort of thing to which the Earth is tending – something dead, cold, and lifeless.”
But not all moons are created equal. Images released this week by Nasa from the spacecraft Cassini, which has orbited Saturn since July 2004, give us a glimpse of a distant lunar landscape that could hardly be more different from the “dead, cold, and lifeless” one that revolves around our own planet. After detecting molecular hydrogen in its plumes, scientists recently confirmed that Enceladus, the sixth-largest of Saturn’s many moons, possesses all of the conditions necessary for life to flourish in the hydrothermal ocean beneath the orb’s icy surface.
Among the more breathtaking images circulated by Nasa is one that captures in a sliver of partial light Enceladus’s poetic profile. Like a ghostly parenthesis punctuating the darkness around it, the crescent offers itself as an open-ended exclamation of awe at a moment when scientists appear on the verge of discovering life in the universe beyond our own atmosphere. The spare scything of light into an icy sickle that intensifies the image calls to mind one of the most extraordinary studies of luminosity in all of art history: the 1766 painting A Philosopher Giving a Lecture on the Orrery in Which a Lamp is Put in Place of the Sun, by the 18th-Century English artist Joseph Wright of Derby.
At first glance, Wright of Derby’s dramatic work invites viewers of the painting to marvel in the elaborate workings of an orrery (a mechanical model of the solar system), whose operation and complex engineering is presided over by a wise scholar, dressed in resplendent robes. The brooding philosopher (likely modelled after the contemporary clockmaker John Whitehurst) may have been connected with the same learned group of intellectuals to which Wright of Derby was himself associated – the legendary Lunar Society, so-called for its tendency to synchronise its insomnious deliberations with full moons.
Though the painting would initially appear to elicit a delight in the whirring of the celestial orbs that are replicated by the orrery, it soon becomes clear that what is really on display are the varyingly-illuminated countenances of the individuals gathered around the galactic gizmo – not the curious contraption itself. Like Wright of Derby’s more famous work, An Experiment on a Bird in the Air Pump, executed two years later, A Philosopher Giving a Lecture on the Orrery relies for its effect on a secreted light source at the centre of the work.
By locating his lamp (as the title tells us) in the very place where the model’s sun would be, Wright of Derby collapses the distance between make-believe and reality. The sophisticated play of darkness and light is intended to echo the ambience of Renaissance religious scenes whose figures bask in the spiritual effulgence of the Christ child at their centre. This effect is given an ingenious twist in Wright of Derby’s hands as he allows the face of each figure to represent a different phase of the moon’s cycle.
The two children who marvel most at the engine’s cosmic spin beam with full-moon cheeks, while the shadowy figure opposite them, sharing our perspective, is in total eclipse. Gyrating from countenance to countenance, our eyes clock the endless waxing and waning of faces from crescent to quarter, gibbous to new. The result is a work that is restlessly kinetic in its whirling wonder of cosmic discovery. Placed alongside this week’s photo of Saturn’s satellite Enceladus, Wright of Derby’s painting reminds us just how far back goes our yearning to see a semblance of ourselves reflected in the heavens – how deeply interior and life-affirming outer space can be.
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