Saturn's Moon Enceladus Could Have Signs of Life

The search for life beyond Earth has been one of the most in-depth searches that NASA and other space agencies have done in the last several decades. Not the least of which is because as we've gone and grasped the true vastness of space it feels almost impossible that there isn't some kind of life out there amongst the stars. To be clear, many aren't saying that it has to be humanoid life or even animalistic-style life, but just life in general. As such, as we look at the various planets and even the moons that surround them, we look for anything that could give us a hint that there is indeed life out there. Which brings us to Saturn and one of its many moons.

In 2005, NASA's Cassini Saturn orbiter discovered geysers blasting particles of water ice into space from "tiger stripe" fractures near Enceladus' south pole. That material, which forms a plume that feeds Saturn's E ring (the planet's second-outermost ring), is thought to come from a huge ocean of liquid water that sloshes beneath the moon's icy shell. This discovery on its own was special because it meant that there might just be water on this moon, and if there's water on it, there's a chance we can colonize the moon as it would allow us to have easy access to water. But a deeper look at the plume itself revealed things that weren't expected. For example, dihydrogen (H2) and a variety of carbon-containing organic compounds, including methane (CH4). The dihydrogen and methane are particularly intriguing to astrobiologists. The H2 is likely being produced by the interaction of rock and hot water on Enceladus' seafloor, scientists have said, suggesting that the moon has deep-sea hydrothermal vents — the same type of environment that may have been life's cradle here on Earth.

For those of you that don't know, the hydrothermal vents there are indeed lifeforms that live there in a way that has often boggled the minds of scientists as a whole. Not the least of which is they some entities are able to go and perform photosynthesis without even needing light because they have the heat and other chemicals coming from the vent itself. So thus if a similar vent can be found here on Enceladus, that would mean that there could honestly be a kind of microbial life form on the moon, and obvious scientists would be very interested in that: "We wanted to know: Could Earth-like microbes that 'eat' the dihydrogen and produce methane explain the surprisingly large amount of methane detected by Cassini?" study co-lead author Régis Ferrière, an associate professor in the University of Arizona's Department of Ecology and Evolutionary Biology, said in a statement.

So Ferrière and his colleagues built a series of mathematical models that assessed the probability that Enceladus' methane was generated biologically. These simulations were diverse; the team investigated whether the observed H2 production could sustain a population of Enceladus microbes, for example, and how that population would affect the rate at which H2 and methane escaped into the plume, among other things. "In summary, not only could we evaluate whether Cassini's observations are compatible with an environment habitable for life, but we could also make quantitative predictions about observations to be expected, should methanogenesis actually occur at Enceladus' seafloor," Ferrière said. Now, before you all start celebrating that 'life has been discovered!' you need to take a step back and realize that these were mainly theoretical equations and suggestions based on the science that we know works on Earth.

Even the team behind this potential ground-breaking discovery aren't saying that they've found life on a moon of Saturn, but merely that there is a possibility of it. They even noted that there is a chance that the excess methane is due to how certain things work on the moon in contrast to how they work on Earth: "It partly boils down to how probable we believe different hypotheses are to begin with," Ferrière said. "For example, if we deem the probability of life in Enceladus to be extremely low, then such alternative abiotic mechanisms become much more likely, even if they are very alien compared to what we know here on Earth." That being said, "biological methanogenesis appears to be compatible with the data," Ferrièr added. "In other words, we can't discard the 'life hypothesis' as highly improbable.

To reject the life hypothesis, we need more data from future missions." And that right there is the key word "more data from future missions". Because as exciting as it is to go and try to say that they have found life on the moon of Saturn, they can't prove it for various reasons because...well...we aren't there. Yes, we've had probes to go and get there, but we ourselves have not been to Saturn and it doesn't look like we'll be able to go there soon based on our own restrictions in terms of space travel. However, should this theory be tested, it could prove a lot of things about not just space, but our own solar system. Think about it, if these kinds of microbial life forms are found on the moon of Saturn...what other moons out there could possibly have a similar thing? Plus, if there is one kind of life on this kind of moon...who is to say there won't be another on a different kind? The irony here though is that technically...this isn't the first time that people believed that there was life of some kind of Enceladus.

"If the conditions are right, these molecules coming from the deep ocean of Enceladus could be on the same reaction pathway as we see here on Earth," Nozair Khawaja, who led the research team behind the discovery, said in a release. "We don't yet know if amino acids are needed for life beyond Earth, but finding the molecules that form amino acids is an important piece of the puzzle." "Here we are finding smaller and soluble organic building blocks – potential precursors for amino acids and other ingredients required for life on Earth," Jon Hillier, another co-author of the study said in a statement. So, if these two things are to go and be believed, that means that, in potential, we have two different ways that life on this moon could exist.

That's something special right there. Of course, the problem here is again...data. It's easy to go and look at things because of the probes that have orbited the planet and its moons for a while and make guesses as to what is there and what isn't. But if you're going to go and make a definitive declaration about something like life, you need to go and get the definitive proof. Whether that happens soon or not is very much up for debate for a host of reasons. Not the least of which is that it's a long way to Saturn and its moons.

The mission project would take a while to plan to say the least, then you'd have to outfit something like a rover or specialized craft to be able to go into the moon (presumably via through one of its geyser pits) and then take samples of both the water in certain places and even potentially go into the vents of the moon itself to get the key samples. Then said craft will have to return to the surface and then fly back to Earth. If that sounds like a lot...it's because it is. That's a lot of work for a singular craft to do, not to mention it would have to be done via a controller back on Earth and so that's a lot of potential for things to go very wrong.

But do we give up on this? No, of course not. Especially if there is indeed a potential for life on the moon. It just means that NASA and its various other allies in the space agency business will need to get creative in order to make things work. It won't be easy, and there will likely be a lot of failures, but if done right, and the patience is there (again, it'll be a long trip to Saturn), they could make it work and make a discovery one way or another. And for NASA, that's a victory in and of itself. Now, some would go and say, "Why can't you just do a piloted mission to Saturn?" Well...that's an even longer experience sadly enough. Let's put it to you this way.

When they did the Pioneer 11 mission, it took that probe 6 and a half years to go and reach Saturn, and that was just a probe! Something that didn't have a lot of mass and other things to weigh it down. Many project that at best, it would take humanity (at the current technology level) about 8 years to go and get to Saturn, let alone one of its moons. And to be clear, that's with Saturn at its "closest" to Earth in terms of their orbits around the sun. If you try and launch at the wrong time? It'll likely take you a lot longer. It's true that companies like SpaceX and others are trying to develop rockets that will take us to places like Mars and Saturn faster, but it won't be THAT much faster. We can only do so much with the technology that we have right now. As a result, we can only use what we have, and that means probes and satellites.

They may not get us all the answers we need, but they're what we're going to rely on. And as teased earlier, with this potential for life on one of Saturn's moons (it has over 80 of them) it makes you wonder (and people at NASA wonder) what else these moons could be housing. Because it goes to reason that if one of these moons have the conditions for a kind of microbial life, so does some of the others. For example, the moon Titan has been touted by many to be a "better spot for human colonization than Mars", and it too has all sorts of methane spots via massive lakes. True, there haven't been any indications that life in any way is causing this, but what if it is? Or, what if it's one of the many, many other moons of Saturn that have this kind of potential? That could lead to all sorts of wonders. Not to mention, Saturn isn't the only one with moons. Jupiter has dozens, Mars has a few that have been heavily studied, and there are plenty of moons throughout the universe that might have certain conditions. So, while all of this is theoretical at present, the potential is just as exciting as we might learn more about the universe through this one moon.