♄ viii

Discovered by Italian astronomer Giovanni Domenico Cassini in 1671 and later dubbed after the titan Iapetus after the naming convention established by William Herschel—with the antiquated adjectival form of Japetian that points to the conflation of the deity with Japheth, brother of Moses—and explored more thoroughly during the 2007 mission named after its discoverer, the satellite of Saturn first loomed large in human imagination when on this day in 1981 the Voyager 2 probe relayed the featured image back to Earth. The prominent equatorial ridge, named the Voyager Mountains after the photograph are among the highest in the known Solar System, and ring the object almost perfectly, giving rise to the theory that the feature is a reabsorbed ring and the probable but yet unseen occurrence of sub-satellites.

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the stars align

On this day in 2012, the space probe Voyager I became the first manmade object to leave the Solar System and enter interstellar space. Twenty-three years earlier—to the day—its companion Voyager 2 made its closest approach to Neptune—then, because of Pluto’s eccentric, elongated orbit, the outer most planet.
On the same day in 1981, it had its closest brush with Saturn.  All these events coincided with the first demonstration of the telescope in Venice in 1609, pitched as a terrestrial telescope or spyglass, having later realised their potential for use in astronomy, publishing his initial observations in a brief called Sidereus Nuncius (Starry Messenger) on 13 March of 1610, including an account of the Medicean or Cosmica’s Stars that appeared to orbit Jupiter.

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tpv-15

Though this image is just about three years old, one of the parting shots of the Cassini probe before it descended into the atmosphere of Saturn, we appreciated the reminder, a sense of proportion that’s much needed right now, from Strange Company of the Earth and the Moon framed by the Encke Gap of the gas giant’s rings—see previously—and for couching it in the POV of the Hitchhiker’s Guide to the Galaxy’s Total Perspective Vortex, a device (see also) originally built as a heuristic tool to demonstrate causality by extrapolating a model of the Cosmos from a single atom.
In application, however, exposing the mind to such a humbling vision of reality was overwhelming and the technology was mainly useful as an instrument of torture—execution, that is, with a final moment of clarity and transcendence. The only biological brain subjected to the Vortex to survive unscathed, protagonist Zaphod Beeblebrox, was only able to do so through the protective bunker of a computer-generated universe that was created specifically to shield him, and with the confidence, hubris that he in fact was the most important person in his paracosm was able to get through the ordeal with minimal amount of insight to put him in his place.

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♄

Via Kottke’s Quick Links we are treated to a scientific assessment and ranking on the accuracy of the Ringed Planet emoji, assuming that they are aiming for Saturn, across differing platforms and operating systems—see previously. Apple’s version is rated most visually accurate, even including details like the Keeler gap in the rings and the polar hexagon though the tilt is over exaggerated by about twice as much.

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georgium sidus

Writing for Æon magazine, historian of astronomy Stephen Case guides us on a fascinating and convoluted process on how the naming conventions of the planets came to be through the lens of the discovery of what we now know as Uranus by William Herschel in March of 1781–the first new planet since antiquity and in (relatively) quick succession what we now call Neptune by Urbain Le Verrier. Whereas Uranus had been marauding through the night sky unrecognised for the planet it is and mistook for a star of the firmament and initially reported as a comet and left to the discoverer’s son to champion, Neptune existence was mathematically derived and then verified through observation, the only standing precedent for naming rights came from the Galilean moons of Jupiter named the Stars of the Medici after Galileo’s patrons.
To the extent that one bothered to differentiate the satellites at all, co-discoverer Simon Marius, astronomer royal of the Margraviate of Ansbach, suggested that they be named after their planetary analogues: the Mercury of Jupiter and so on—before ultimately being named for paramours of Zeus. The elder Herschel had named his discovery after George III, somewhat of a consolation for loosing the American colonies, a decision his son and intellectual heir regretted but was adamantly against the counter suggestion by Le Verrier that they name the planets after themselves. The younger Herschel found a way out of this impasse by returning to the subject of naming satellites—specifically for those orbiting Saturn, a couple of which he had discovered himself. Mythologically awkward to name the moons after family members of the Titan who deposed his father—Ouranos, Uranus incidentally—and devoured his children, Herschel proposed naming the moons after peer giants and giantesses. The matter was settled and extended to keeping the planets named after Greco-Roman gods—rallied by choosing to call a newly isolated element uranium after the ancient sky deity. By dint of the sheer number of Cronian satellites, giants from other pantheons are admitted as well. Though arguably installing an Anglo-American hegemony among the stars, the International Astronomical Union while not neutral does promote inclusion in its work. Though eschewing the honour himself, the Hawaiian term (whose own legends are enjoying more representation) for Uranus is Hele’ekala, a loan word for Herschel.

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afterthought

On this day in 1966, three days after the discovery of a Cronian satellite (see previously) dubbed “Janus” by Audouin Dollfus, astronomer Richard Walker recorded a similar observation of what was then considered to be the same small moon, the scientific consensus at the time being that two objects could not share the same orbital pathway without colliding despite the fact that this interpretation meant that Janus was hurtling around Saturn much faster than is the case.

A dozen years later, more precise measurements resolved the observations to that of two distinct but co-orbital bodies, and because of this hindsight, the latter credited sighting was named Epimetheus—the twin of the Titan Prometheus associated with foresight. Whereas we might regard Prometheus as more heroic and selfless for daring to steal fire and the other civilising arts from the gods than his dumb brother, whom for unconscionable reasons was entrusted to hand out gifts from

 Pandora (all three also in that same constellation of satellites), as a consolation prize to make up for the fact that all other traits, strengths had been apportioned to other animals, it was sort of a thankless sacrifice (aside from it being a distinct lack of appreciating the consequences of his actions) Prometheus stood trial as was condemned to an eternity of suffering. Epimetheus, on the other hand, demonstrates that we are part of a larger, virtuous network and that dependency and social contracts are themselves strengths (in as much as is the leftover hope) and wound up marrying Pandora, whose daughter and son-in-law are the only humans to survive the flood when the gods decided ultimately to drown mankind. This inner satellite is also referred to as Saturn XI and its gravity and orbit help to define its hosts rings, shepherding rocky debris and dust in place.

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ymir and járnsaxa

With the discovery of twenty more natural satellites in its orbit this year, the cronian constellation surpasses Jupiter as the planet with the most moons, an astonishing eighty-two.
The new moonlets are distant objects travelling around Saturn in the opposite direction from the inner moons and are suspected to be captured asteroids and are part of the Norse group—the International Astronomical Union (previously) reserving the naming-convention to figures from Nordic mythology (see also), mostly after giants and giantesses, with the exception of Phoebe, named after a Greek Titaness discovered in 1899, before the establishment of the IAU and the first moon discovered via photography. The public is invited to take part in coming up with their official designations.

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saturn vi

Though exploration of the Cronian satellite cannot begin before 2034 (distant-seeming but only fifteen years hence), NASA has committed, choosing among twelve contending proposals, to send a fleet of aerial drones to survey Titan, more planet than moon-like with a dense atmosphere, complex terrain, weather and methane driven precipitation similar to the water cycle on Earth, only sustainable at much lower temperatures, to seek out alien life.

Extra special care and precautions are being factored into the Dragonfly mission so as to not disturb the primordial conditions of the surface as the craft take samples of the moon’s chemistry. Under this frozen substrate (see also), which while having the necessary building blocks for life as we conceive it, scientists believe there is a water-ammonia lies a panthalassic ocean where abiogenesis is suspected to have occurred.

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♄ ii

Not only have astronomers possibly deduced the mechanisms that generate and sustain heat to keep the subsurface ocean of the Cronian moon Enceladus from freezing over but can also extrapolate from their research that there has been a watery environment under the frozen shell for billions of years.
The satellite is named after the primordial giant (dread offspring of the Titans) that sparred with the Olympian goddess Athena in the Gigantomachy, and vanquished was buried beneath Mount Ætna. Attributed as the cause of volcanic eruptions and earthquakes, scientists had their curiosity about the tiny moon piqued when they observed dramatic geysers of water shooting out of the southern hemisphere and seeding one of Saturn’s outer-most rings, and they thought an ocean might be hiding below as with Europa. Presumably, the age of the ocean would be long enough and stable enough to allow life in some form to gain a purchase and adapt to such harsh conditions. Looking out at this distance, delicate arrangement (though others might think that a barrier of ice is far more sheltering that the cold, open sky) makes me lament how careless we are with our ecosystem and hope that we might not have to learn the hard way.

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crest and trough

As Kottke informs, during one of its final passes of the Saturn system, the Cassini probe (previously) delivers an image of a spiral density wave in one of the planets rings that illustrates the complexity and nuance of gravitational relationships. The ripples are caused by the waltz of two satellites, Janus and Epimetheus, which share the same orbital path and trade places as leader and follower with a period of four years. Like extracting historical data from tree growth rings, gauging the distance between the waves reveal details about past trajectories.

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status nascendi

New Scientist and several other sources are excitedly citing findings on a chemical, topographical study on Saturn VI (the moon of Titan) from Strasbourg's Space University (that's a pretty snazzy alma mater) as possibly indication of alien life.  Akin to noting that concentrations of oxygen were inexplicably less at the surface of the Earth, research has revealed that there may be a respiratory exchange of hydrogen for methane on Titan, for which life forms could account, from unexpectedly low concentrations below at certain altitude.  I imagine that such aliens would be like nothing decades of sci-fi fandom have primed us for, no humanoids that are political animals in any familiar way or disembodied intelligences, but delicate membranes carried aloft on the wind like jellyfish in the sky.  After all, humans are still only just recognizing that whales are not just prey or dolphins not just gay sharks, not to mention the wealth of living things that lie just below our line of sight.  Nonetheless, it is certainly news to get goosebumps over.

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