The Wonder of the Solar System
You rarely see “wonder” among the rationale for human space exploration and expansion. But capturing this sense and experiencing it with those we care about should be considered among the reasons to travel from Earth or to leave it entirely.
Recently I played through Super Mario Bros. Wonder, aptly named as it’s the most successful attempt I’ve seen to distill this hard-to-define sensation into a 2D game world.
But we shouldn’t have to retreat to video games or virtual reality to kindle a sense of wonder. The most cutting critiques of the Apple Vision Pro are not about the limits of the hardware in its first version; instead, they focus on the depressing, lonely future it portends. This is coming on the heels of sobering looks at the effects of smartphones now that we have enough years of data to see them clearly.
Back in the physical world, babies seem to live in a permanent state of wonder. Just look:
Throughout childhood there’s plenty of opportunities to continue experiencing wonder, even if many of these are contrived by adults. Christmas morning. Disney World. Reading through Harry Potter. A first snowfall. Watching a butterfly emerge from a chrysalis.
As we get older these encounters with wonder begin to fade. Eventually they’re only brought on by traveling to unique natural environments like Iceland, or perhaps Zhangjiajie, attending festivals and concerts, or taking psychotropics–sometimes in combination with the former. But the magnitude of the effect is lower. It wears off faster. How can we expand it?
The wonder that comes with looking down at Earth from space is well documented, and this is just a taste of what’s on offer within the solar system. Wonders–in noun form–come in seven, and I’ve put together a list of places and features I think are most likely to evoke this sense when experienced from a first-person perspective. Lists from others would probably feature big things like Valles Marineris or Olympus Mons, but from one side of Valles you can’t see the other, and on Olympus you’d be hard-pressed to know you’re on a mountain given how gentle the rise is.
1. Lunar Lava Tubes
Lava tubes on Earth are neat to walk or crawl through, but the ones on the Moon are gargantuan. Recently revised estimates put their widths at up to 300 m: cathedral spaces large enough to fit skyscrapers. You’d rappel into the tubes from skylights which also let through a beam of light flooding the interior space. Collapsed rocks the size of apartment buildings litter the floor around these entranceways. The light fades to pitch black down the tens of kilometer lengths of the largest tubes, where we have little information about what we’ll find. The first explorers of these caves will experience something more profound than Neil and Buzz’s puttering around on the surface regolith.
2. Martian Spiders
All of Mars has a stark, quiet beauty to it. But near the southern polar latitudes Mars comes to life during the southern spring as dry ice laid down during winter begins to warm. I’ll quote extensively from Hugh Kieffer here:
With the initial spring sunrise things happen much faster on equatorward slopes, whether sides of rocks, or spider-mounds or dunes or longer slopes. Most of the sunlight is absorbed in dust grains distributed roughly uniformly through the CO2; these form tiny pressurized gas bubbles and migrate down or along ice-grain triple junctions to upper or lower slab surface, leaving clean ice. Sunlight then is absorbed by the underlying soil surface and the slab sublimes from the bottom. The ice surface heaves and falls as the sub-slab pressure builds and is relieved when new vents open. Weaknesses break to initiate vents, allowing the CO2 gas to escape as cold jets. In many places, this gas entrains dust which falls out adjacent to the vent or is broadcast downwind as fans
The jets themselves are nearly transparent, above eye level the opacity drops quickly, although well-shaped vents generate jets up to 150 m high. Down-wind from the jet, the grains fall out, bounce a bit. Dust in sunlight absorbs heat, so the grains cannot stay in contact with the ice, they must constantly be in motion, jostling around in little dimples and working their way down-slope…until their abundance is adequate to form a mat. This leaves humps of clean CO2; another positive-feedback process
Perhaps the most peculiar vent-related forms are “spiders”, also called araneiform terrain; radiating, dendritic, bifurcating forms of channels that narrow downhill. Although venting is an erosional process, somehow the spiders [grow] into mounds over time. Spaced semi-regularly across level terrain, there are many varieties: thin, fat, patterned, isolated or being so dense they grade into connected lace terrain.
These aren’t the typical rock-strewn environments we’re familiar with. And it’s not just the visuals: the popping and cracking of the erupting vents will carry well through the thin martian atmosphere.
3. Io Lava Falls
Io is fire and brimstone in moon form. Quite literally too: its yellow-white-red palette comes from sulfur (brimstone) compounds in its volcanic emanations being exposed to the charged particle environment around Jupiter. In some cases, lava flows reach cliffs with vertical drops up to 3 km. This puts Mustafar to shame. Because there’s no atmosphere there’s no terminal velocity either. The lava will reach speeds of 100 meters per second, and any quench crusts formed around falling blobs will explode open when they smash into the molten ponds below. Jesper Sandberg has a fantastic write-up of the Pillan Patera eruption in 1997 that inspired this placement on the list.
4. Rings of Saturn
Lots of films depict flying through an asteroid belt like this:
In reality, in the densest part of the asteroid belt you’d see this:
Not much wonder here. The rings of Saturn are different. Here, ice particles range from dust-sized to mountain-sized, and in the dense A, B, and C rings they’re packed in, separated by only centimeters to meters. It’s a chaotic environment with grains constantly colliding, forming tenuous vertical structures, and coagulating into temporary moonlets that then break apart again.
A spacecraft matched to the speed of the rings could go along with the flow, dipping above and below the plane to cut a swath through the icy shards.
5. Flying over Titan’s lake district
Saturn’s largest moon Titan has such a unique combination of low gravity and high atmospheric pressure that as others have calculated, with Icarus-like wings strapped to your person you could fly by flapping your arms. Where to, though? Titan’s water-ice crust is pocked with rivers, lakes, and seas of liquid ethane and methane that rain down from its haze and cloud decks. They’re lined with solid organic sludge which elsewhere on the moon blows around to form vast fields of hydrocarbon dunes. And hey, the northern lake district has more shoreline than Lake of the Ozarks.
6. Geysers of Enceladus
The tiger stripes of Saturn’s moon Enceladus tap into a subsurface sea or ocean beneath its ice shell and vent warm saline waters into geysers that erupt over 500 km high. These displays can be viewed from a low-altitude orbit that flies directly through the plumes themselves, or from the surface standing on a plain of fluffy snow while more freezes out of the geysers and floats down to land around you. All set against the blackness of space.
7. Pluto’s Nitrogen Glaciers
The beating heart of Pluto, Sputnik Planitia, is a vast plain covered in solid nitrogen that fills in an ancient impact basin. Flowing nitrogen glaciers embay into a more rugged cratered terrain where mountains made of water ice are capped with frozen methane. Could you ski here? Lines for the lift have grown long at Breckenridge, but they aren’t too bad at the edge of the solar system with an imposing Charon orbiting overhead.
People travelling freely through the solar system will soon exhaust this list and the wonder will start to dwindle. But at that technology level we can build artificial wonders that serve the same role, just as the ancients did. In the game Age of Empires, the pinnacle of the tech tree was to build a Wonder. It didn’t serve much role in the gameplay and was more of a flex for winning at life. Is that all that there will be left to see?
I think the solar system is barren of life outside Earth. If proven out, this impels us to make the jump across solar systems and seek out the most interesting sources of natural wonder: new types of worlds, and with them the hope of new ecosystems to explore.