The first teaser trailer for Avengers: Endgame dropped last week, featuring a universe devoid of 50 percent of all living things thanks to Thanos’ extremely poorly thought-through ecological genocide. The Big Bad was inspired to wipe out half of all life after watching his home world of Titan descend into chaos when it couldn’t feed its populace anymore.
However, after consulting with scientists, it’s clear the real problem on Titan wasn’t overpopulation, but the decision to try and live there at all.
Titan in the movies is, according to Marvel’s president, a distant planet, but in the original comics, it’s the eponymous moon orbiting Saturn. Although now left in ruins, Thanos and company once inhabited Titan, shown in flashbacks to have blue skies, flowing water, and green vegetation. Thanos can be seen breathing fine without any equipment on Earth, so along with those flashbacks, we can assume Titan was transformed into an Earth-like world.
What would it have been like to live on Titan before all this geoengineering took place, and what would it take to transform it into planet like Earth? As it turns out, although not the most inhospitable place in the cosmos, Titan would have been an incredibly freaky place to live in its pre-terraforming days. More importantly, its transformation, and decline, highlights the limits of trying to bend nature to our will.
The largest moon of Saturn and the second-largest in the Solar System behind Jupiter’s Ganymede, Titan is in some respects already Earth-like. It is the only moon with a dense atmosphere and the only other body in the solar system with seas and lakes at its surface. There are some major differences though: its gravity is more than seven times weaker than Earth’s, and the surface is extremely cold, coming in at -179 degrees Celsius (-290 degrees Fahrenheit). Because of the temperature and its geochemical makeup, Titan has a water ice crust with rivers and lakes of hydrocarbons, like methane and ethane, flowing over it.
“In terms of life as we know it, the temperatures at the surface present the biggest challenge,” Sarah Hörst, an assistant professor at Johns Hopkins University’s Department of Earth and Planetary Sciences, told Earther. At those temperatures, “water behaves more like granite than anything we’d associate with water.”
Michael Malaska, a scientist within the Planetary Ices group at NASA’s Jet Propulsion Laboratory, agreed that the extreme cold could be a “deal-killer.” And if the cold didn’t kill you, Titan’s oxygen-lacking atmosphere would cause asphyxiation within minutes. Malaska also noted that the combination of extremely low temperatures and an atmospheric pressure 1.5 times that of Earth’s “would make walking on Titan more like swimming through a down pillow.”
Hörst said that that Titan’s weaker gravity would probably be the least concerning aspect in terms of survival. In fact, the thick, dense and deep atmosphere, combined with Titan’s low gravity, means that you could simply flap your arms and fly under your own power, so exploring, and transporting supplies around at the surface would be a breeze.
There are, however, other distressing aspects of Titan that outweigh the ability to glide with ease. Earth’s biochemistry would have very hard time dealing with the dominant chemistry present on Titan. “Liquid methane is a really crappy solvent,” Malaska said, explaining that very basic biochemical strategies, like transporting energy-containing molecules like ATP, wouldn’t work without a decent solvent like water.
Terraforming Titan to be more like Earth would be “extremely challenging” to say the least, said Hörst, and perhaps impossible. Becauase the Sun is so far away, it would likely be impossible to raise the surface temperature high enough for a person to go for a meander outside. She suspects enclosed habitats are the only way forwards, similar perhaps to the domed vacation resorts referenced in the science fiction series The Expanse.
Unfortunately, even if future technology existed to warm Titan up—this handy comic book chart appears to show that “fusion arcs” hanging in a sky vault would be used to replicate the Sun’s warmth and light—doing so would create enormous problems. The icy water crust would melt on top of an already substantial subsurface ocean, creating what Malaska estimates to be a 200-kilometre (124-mile) deep global sea, perhaps featuring some floating rafts of icky organic polymer.
“Maybe you could build on these floating organic blobs?” Malaska wondered. “Or transform them into Tupperware wonderlands?”
You’d also need oxygen for breathing and crops, which could perhaps be acquired by electrolysing the subsurface caches of liquid water. Global oxygenation could also help get rid of a global layer of haze which blocks out sunlight and has an anti-greenhouse effect, keeping the surface even colder than it otherwise would be, according to Hörst. Even without the haze, though, it’d still be frigid on the ground, and there’s no guarantee that fresh oxygen would be retained on gravitationally weak sauce Titan.
All this geoengineering would require a colossal amount of energy perhaps generated through wind, chemical or potentially hydroelectric power–and would, says Malaska, require plenty of compounds you can’t get easily on Titan. Mining of comets or asteroids would likely be essential.
Without his Infinity Gauntlet, even Thanos would find making Titan somewhat Earth-like would be a considerable pain in the ass. It’s enough to make you realize we probably shouldn’t put too much faith in the idea that in the future, terraforming worlds will simply be a done deal. As the ultimate collapse of Thanos’ Titan—apparently due to mass starvation—reminds us, there are a thousand points of failure.
Earth itself is so conveniently, wonderfully suited for life as we know it. Perhaps we should remember that, and the limits of geoengineering, as we continue to trash it.