What If We Seeded Life on Another Planet? | Unveiled

What If We Seeded Life on Another Planet?

From our position in space, life seems pretty rare. So rare, in fact, that “life on Earth” is as much as we can account for. We’ve now been searching for extraterrestrials for decades but, so far, we haven’t found any. If life really is as uncommon as we so far suspect it to be, then is it down to us to ensure that it continues and spreads?

This is Unveiled and today we’re answering the extraordinary question; What if we seeded life on another planet?

How did life come to be on Earth? There are a range of theories, including the idea that we emerged out of a primordial, prebiotic soup billions of years ago, as well as other proposals which argue that maybe it didn’t actually start on this planet at all. The Panspermia Hypothesis suggests that life on Earth was seeded here via organic matter brought from elsewhere by asteroids and meteors. Regardless of how we got here, though, Panspermia is an idea that could feasibly affect us at the other end of the debate, too - we could become the ones doing the seeding.

In fact, we may have even done so already. The Voyager probes, humanity’s furthest-flung machines in space, for example, weren’t sterilized to today’s higher standards when they were launched out into the cosmos in the ‘70s. And, given all of the space missions we’ve seen in just the last few decades, there have already been countless moments when germs and microbes from Earth may have been unintentionally sent toward other planets, moons and asteroids. Even today it’s possible that there are thousands of cells still alive somewhere on the Voyager crafts, ready and waiting to rest and multiply on some other distant world in the future.

To some extent, accidental Panspermia goes hand-in-hand with our desire for space travel; it’s arguably unavoidable. But, were we to purposefully seed life somewhere else, then what would be our motive? Well, for one, the continuation of the human race. As we aim to venture further out into the solar system, we do so in part to find other planets that are like Earth or that can be terraformed to become like Earth. And, in a worst-case scenario where the real Earth for whatever reason becomes uninhabitable, then humanity can survive on whichever planets we’d most successfully adapted to meet our needs.

Therefore, the planets most likely to be seeded are probably also those closest to us and those most likely to be deemed habitable; with Mars being a leading contender. Variations on the Panspermia Hypothesis even theorize that we - the human race and all of Earthly life - are originally from Mars, brought to this planet thanks to seeding from there to here around four billion years back. If that were the case then with Mars we’d only ever be re-seeding our first home!

Looking further afield, we might also try seeding life on the Jovian moon Europa, which is arguably the solar system’s leading candidate in terms of its potential to host life. Or, at a future time when the vast distances of space are more manageable to us, we could choose to facilitate Panspermia on any of the other possibly habitable exoplanets we’ve so far discovered. Beyond it offering a chance for humanity to extend its life in the universe, seeding a planet could also have broader research applications too; enabling us to find out more about the evolution of life, to see how complex organisms come about in real-time, and to study how life adapts to extreme conditions. It could give us greater knowledge than ever before about our place in the universe and how we came to be.

But, that’s not to say that we should just go ahead and seed humanity wherever we can and as soon as possible! It’s not all good or even encouraging news… and there are already rules in place to avoid contaminating alien planets. We don’t want to introduce life and disrupt an existing extraterrestrial ecosystem; we also don’t want to accidentally seed life on another planet that we could later mistake as having originated from that planet; and we don’t want to cross-contaminate during a return mission, thereby losing track of potential alien microbes that we could also be redistributing. Today, you can work for NASA as a Planetary Protection Officer, whose job it is to ensure that these practices are followed.

More than over-cautious science, there’s a major ethical debate at the heart of this question, too. Say humans were to one day arrive at another planet where they know simple life already exists or they don’t know for sure that it doesn’t… any deliberate attempt to seed our own strain of life could alter the evolutionary path and disrupt the nature of that other world. One way to sidestep the “great unknown” of sending humans anywhere that might (or might not) harbour life could be to use artificial intelligence, instead. Theoretical Physicist Claudius Gros has proposed seeding life through what he calls the Genesis Project. The idea is to have purpose-built probes carrying organic material sent to alien worlds, but each probe is controlled by an on-board AI which can reliably determine whether life already exists from afar… If it doesn’t exist, then the probes are deployed; if it does, then they’re not. For Gros, the AI tactics could then be prolonged to help the microbes that it does let loose to fast track into more complex life forms… leading to a future time when humanity can safely seed and monitor life across multiple galaxies, without ever traveling to most of them itself. It’s hoped that a Genesis Probe could even be built and in operation by the end of the 21st century… so, watch this space!

While something like the Genesis Probe would afford us a degree of control, however, if we really were to seed a planet then we could expect all kinds of new and unique creatures to spawn in time. Life generally adapts to its surroundings, with Earth hosting millions of species itself, but there’s really no telling what kinds of adaptations would take place to align with a never-before-seen, alien environment. In this way, a planet-seeding project could go further than simply discovering whether life itself is rare, by determining whether intelligent life is also something which can be replicated. For some, intelligence is the logical end goal for all evolution, while for others it’s more an extremely unlikely and uncommon occurrence. Is humanity simply one stage in unstoppable progress, or are we purely the product of a long-winded coincidence?

Were we to seed a new planet from scratch, then we could begin to answer that question… and, in the event that another intelligent species did arise over time, then we’d have an interplanetary link all of our own making; but one which could cause problems in the future. Were the beings we had seeded to discover their human creators then they could come to see us as something like Gods. Equally, though, they could come to resent those on Earth, or life on Earth could come to resent them… especially if their intelligence were to ultimately surpass humanity’s own. On the one hand, we could forge an alliance and work together to seed more planets in much the same way; on the other, we make an ultra-advanced enemy of each other.

But, either of those outcomes is a long, long way into the future. For now, human-led Panspermia is a thought experiment only, and not something we’re truly at risk of carrying out right away. Hypothetically, if humanity ever was faced with extinction on Earth, then it really could be our only hope for survival; meaning our end wouldn’t necessarily be the end of all life. Similarly, if we ever do hope to live on other planets, then it could be a crucial part of our early plans. There are major ethical questions at play, but that’s what would happen if we seeded life on another planet.