Carried Off by an All-Powerful Eagle

Jupiter and Ganymede (Roman, late 3rd century) mosaic

Yesterday’s post about the solar system’s largest moon, Ganymede, begs for a follow-up post about the myth of Ganymede. Ganymede was an adolescent Trojan prince known for his supreme comeliness. For some reason, the young prince was out slumming as a shepherd (which is a thing princes do in myths but not in real life) and this twinkish coquetry drove all-seeing Zeus into a lather. Overcome by lust, the king of the gods assumed the form of a giant eagle and grabbed the pretty prince up in his talons and carried him off to Olympus (leaving Ganymede’s distraught hound dog baying at the clouds). At Olympus, in the halls of the gods, Ganymede became the cupbearer (and favorite male concubine) of Zeus/Jupiter and was thus granted immortality and a sort of second-rate godhood. The whole tale is a sort of a gigolo apotheosis (although classical artists did not always portray Ganymede as a willing captive).

For various reasons, all sorts of artists have been attracted to the tale over the years. The magnificent sky-god eagle and the beautiful nude prince do indeed make for a really dramatic tableau. Yet my favorite visual representations of the story are Roman, like this gorgeous relief.

Abduction of Ganymede (unknown Greco-Roman sculptor, AD 140-150), marble relief

As slave-owning masters of the world, the Romans knew the ambiguous joys of love-by-command and somehow there is always a wistful hint of coercion and mortal sadness in Roman versions of the tale (perhaps the Greek sculptors forced to carve these pieces had some commentary of their own to add). For example, in the matchless piece above, the beautiful Ganymede wears a Phrygian cap (which was a cap from Phrygia, a conquered Roman province in Greece…but also the universally understood symbol of a manumitted slave). Now, that I come to think of it, Jove’s eagle was the symbol of the Roman Empire.

Ganymede feeding the Eagle (Roman, late first century), Marble

Of course, there is more than a hint of mortal sadness in the tale anyway. We mortals have a name for when the gods snatch away our favorite people and carry them off up to dwell in cloudtop palaces forever. Maybe this is why the Ganymede theme appears again and again in Roman sarcophagi and funerary art.

Here is an example which was carried off by the English at the height of their Empire and placed in the British Museum!

Pictures from Ganymede

Hi everyone! Sorry that the posts were thin on the ground last week. The head druid told me that I needed to honor the solstice by taking some time to reflect on the meaning of things [citation needed]. Anyway…since I didn’t blog last week, I failed to post these astonishing pictures of Jupiter’s giant moon Ganymede, which were photographed by NASA’s Juno spacecraft as it slaloms though the Jovian system.

Ganymede as imaged by NASA probe Juno

Although its lack of atmosphere and pockmarked plains of dust make it superficially resemble Earth’s moon, Gannymede is a very strange and unique heavenly object Of the 200 known moons in the solar system, it is the largest. Indeed it is 26% larger than the planet Mercury by volume (although it is only 45% as massive as the metalliferous first planet). Ganymede has a diameter of 5,268 km (3,273 mi), so each pixel in the full size image of the Jovian moon is equal to a kilometer (although you may want to check out the NASA image to really savor that scale–since WordPress has a noteworthy penchant for scrunching up my images in incomprehensible ways).

A photo of the dark side of Ganymede taken by Juno’s incredibly light sensitive navigational camera

Alone among moons in the solar system, Ganymede has a magnetic field, albeit a rather meager one compared to Earth or Jupiter. Scientists surmise that the magnetic field is created by convection within the liquid iron core of the moon–although answers are not forthcoming as to why it has a liquid iron core to begin with (these planetary cores seem to be the real determinant of what planets are like, but I feel like we know precious little about them). Thanks to its size (and maybe thanks also to its magnetosphere), Ganymede has a very thin oxygen atmosphere…but that just creates more question, since elemental Oxygen has a tendency to instantly bond to all sorts of other elements. The 20 percent or so of oxygen in Earth’s atmosphere did not become a mainstay until about 1.5 billion years ago when photosynthesizing bacteria finally became so prevalent that they overcame the constant loss of atmospheric oxygen thanks to oxidation. Hopefully Juno’s survey will help us solve atmospheric mysteries on Ganymede. Ganymede is also believed to have a vast subsurface ocean of icy water tucked away somewehere beneath its surface. Astronomers have reasonably speculated that this Ganymede underworld ocean may contain more water than all of Earth’s oceans combined!

This is the largest version of this interesting cross section which I could find

Ganymede is a Galilean moon–which means it was discovered by the great scientist, and is one of the first objects ever discovered to orbiting another planet (I still sometimes imagine the thrill Galileo must have felt when he realized what he was seeing). I wonder what surprises Juno will send back for us!