What Do Europa’s Shallow Lakes Mean for Us?
Recent reports indicate that Jupiter‘s moon Europa may have small lakes much closer to the surface than the immense ocean long thought to exist beneath its thick frozen outer layer. According to the researchers, this not only improves the chances of life developing, due to an exchange of nutrients taking place between the lakes and the ocean, but also makes a mission aimed at searching for life inside the moon significantly more plausible.
In itself, this sounds terribly exciting. Europa has been a strong candidate for extraterrestrial life ever since we have started to actively explore and try to determine what conditions could be required in order for life to appear and persist on a world, so any such reports make us dream of the long-awaited confirmation even more and the supposition that there may be enough oxygen in the water to even allow for advanced life forms only puts the icing on the cake. However, as always when it comes to science, we must take a step back before we leap forward, putting our hopes and dreams aside to analyze these findings somewhat more objectively for a moment.
We’re talking about a celestial body that almost certainly contains liquid water, which is considered to be the primary requirement for life. However, said water is not found on the surface, but well beneath it, and it doesn’t stay liquid because the required temperature can be found anywhere in Europa’s depths but because other processes keep it liquid in spite of the extreme cold, the predicted temperatures being well below the lower limit at which life has so far been known to exist. What’s more, the water in these small lakes is very likely to be colder than the one in the ocean, seeing as they are much closer to the frigid surface and surrounded by ice.
Additionally, we’re talking about a moon of Jupiter, and Jupter releases huge amounts of radiation. On the one hand, that does make for interesting reactions, which may well provide the necessary ingredients and accelerate the development of life. On the other, that same radiation would make it even harder for life to persist, greatly harming and likely killing any living organism that would develop. Once again, the lakes would receive even more of this radiation than the ocean, being closer to the surface and therefore less shielded, so any life forms are likely to have an even harder time surviving in them.
And then there is the obvious lack of sunlight, which affects both the lakes and the ocean equally, seeing as being covered by three or thirty kilometers of ice makes no difference when it comes to that. Then again, Jupiter, and therefore also Europa, receives roughly 25 times less sunlight than Earth, so there wouldn’t be much of it available to begin with, even if the liquid water would somehow be on, or somehow connected to, the surface.
Of course, life could take many forms and thrive in all sorts of conditions, some of them being well outside of what we would now consider to be suitable. At the same time, we need to determine what the suitable conditions could be in order to know both where to look and, to some extent, what to look for. After all, life forms that would thrive in conditions that we wouldn’t deem to be suitable for life may well look and behave in ways that would make them hard or even impossible for us to detect. In fact, they could even be “alive” in ways which we wouldn’t currently define as such, meaning that we’d likely ignore them even if we would somehow notice them.
On top of the discussions about the possibility of life on Europa, we must also see whether we could properly investigate even these lakes, not to mention the ocean itself. After all, digging through what may be as little as three kilometers of ice to get to such a lake may indeed be much easier than digging through as much as thirty kilometers to reach the ocean, but we’re still talking about digging through kilometers of ice on a relatively distant world, all the while withstanding frigid temperatures and significant radiation. Not to mention that we’d need to accurately pinpoint the location of such a lake through all those kilometers of ice before we could even begin to dig towards it.
It seems like a lot to ask of the equipment, considering our current technological level and the lack of any previous missions that could in any way be considered to be similar. It would be an enormous undertaking, which in itself sounds rather unlikely when you see how funding for science keeps being slashed lately, regardless of the discussions we keep seeing about it, but it would also be a very risky one. Any such mission wouldn’t only need to get past the difficulties described above, but also to do so without causing any potential harm to any potential life that could exist on Europa, whether detected or not, which would imply not causing any changes, not releasing any substances and not leaving anything at all behind. If it wouldn’t be done extremely carefully, or if anything at all would go wrong, we would most likely end up interfering with any potential life, altering, harming and possibly even destroying it completely, which is something that must be avoided at all costs.
In the end, I don’t see this new report as changing too much. The mission would be extraordinarily difficult either way and sending equipment capable of exploring the ocean, possibly also more or less briefly analyzing one or two such lakes if it’d happen to find them on the way down, still seems like the best bet, seeing as simply exploring one such lake and not finding anything wouldn’t mean much about the possibility of life on Europa as a whole. However, considering the enormous risks involved, both for the equipment and for any potential life that could be affected by it, I don’t think that such a mission should be attempted as soon as possible, but instead another should be sent before it, to a target far less likely to harbor life, in order to thoroughly test everything.
Considering all the budget cuts, even making this mission happen seems unlikely, so sending another one before it only to test how it’ll work out is basically impossible, but I can hope. Who knows, from a technological point of view it may be possible to build something that could start such a search for life a decade from now, as it seems to be planned, but I fear that they’ll need to cut all possible corners in order to have any chance of getting it approved by then, resulting in a mission perhaps more likely to destroy than detect… Making us the destroyers of two worlds instead of just one.
