03 August 2018

Is water on Mars = Life on Mars?

Recently, a scientific paper was published about an underground lake detected on Mars. If this result is confirmed, a significant change is coming.

What follows are wild speculations moderated with scientific thinking. Mind you, I have a vivid imagination, so vivid that I can write stories (I published a few in my native language, and am preparing one for publication in English). This means, for me, I have to use the strict scientific method to moderate my speculations so that I can stick to reality and logic as much as possible.
So I said, change is coming. If that lake exists, and there is a quite high possibility that it may, then our approach to the Mars exploration will have to change.

The first step will most likely be to confirm the existence of the lake using some different instrument. The original result was published using MARSIS. Scientists used data from 29 orbits in last 6 years. The work was methodical and detailed, so it seems like we should believe them. The trouble is, the second radar instrument that flies around Mars, SHARAD, cannot see it. It cannot penetrate the layers above the lake. The instruments use different wavelengths, and that very well might be a problem, but the catch is, we really do not know. I personally doubt that there is an instrumental error. The journal Science has strict editors and reviewers, so the chance that we're talking about the same blunder like that one with neutrinos faster than light a few years ago is very, very low.

But let us be optimistic and say that confirmation will happen and that there is water under the surface. Because if there is water, we will face another interesting problem.
The potential for life on Mars.
If there is liquid water on Mars, we might find some Martians as well. Granted, they will probably be just microbes, but they will answer loads of questions. The reason why they are most likely microbes is that lake is underground and very, very salty. You see, Mars does not have geothermal energy, its core is cooled down. Mars is cold, and any water at those depths has to be at a temperature below the freezing point of the water at all times. After all, the lake is more than a kilometer underground. Also, the lake does not have any layers of ice above pressing the water, meaning the point of freezing is not changed due to increased pressure. Nope, the only possible solution is a high percentage of the dissolved minerals in it. There is a probability that there are many salts in it, that it is poisonous for even the most extremophilic of Earth's microorganisms. However, that still does not exclude a possibility that there might be life.

And that life will open a whole new ‘can of worms.’

Let us start with the most exciting possibility. There is speculation that life in the solar system first began on Mars and then spread to Earth. Meaning, we might well be Martian offspring. Finding Martian DNA would answer that question. And that is quite a question.
Depending on that answer, the famous Drake equation will be modified to reflect the more realistic state of life in the Universe. Because, if we are not Martians, and the life independently arose on Mars and Earth, that will up the probability of us meeting aliens. But if we are, the chance will go down.
In any case, finding a microbe outside the Earth will be a significant discovery.

Also, we could find nothing. But if you’re someone who cheers for space colonization, you might actually prefer this option. Because if there is just water, too poisonous for any life, then we will have less opposition to colonize Mars. And it will be easier to establish a colony closer to an existing water source. Even lousy water can be used to make concrete. Especially because the area where the lake is found, the South Pole, is not geologically unique. Meaning, there is a chance that similar lakes exist elsewhere on the planet. You can bet that right now, after this publication, teams behind both SHARAD and MARSIS will painstakingly study data covering the rest of the planet, looking for a similar signature. Evidence for additional water would indeed be suitable for the colonization.
But first, we need to confirm the existence of water, then see if there is life. This means a new instrument needs to be sent there to examine the location. Hopefully one of the existing missions in preparation has something that might be modified for such purpose.

There is talk of sending equipment to drill into the lake. In truth, that is not very likely. We need to drill a kilometer, and without humans operating such equipment, that might be too tall of an order.
But taking a sample of water is a necessary step to see if there is life. Any mission to accomplish that particular task needs to be developed from scratch. Given the current anti-science movement and reductions in science funding, the whole project might easily take a decade. So do not hold your breath. Actually, a mere decade is an optimistic estimate. NASA and comparable agencies across the world, plan their research missions for several decades in advance, because it takes time to do problem-solving of the particular project, especially when you cannot just stroll to Mars and test the equipment -not to mention that a buffer against flip-flopping politicians has to be included in the plan.
Anyway, it will take time and serious problem-solving. Just remember that last report which said that Curiosity met a rock it cannot drill. And Curiosity drills very shallow holes, just enough to get a sample for the onboard analysis instrument. And, we’re talking about the drill bit capable of tackling most of the rocks on the Earth. This latest little snafu is a problem which needs to be solved before we even start working on a drilling mechanism to explore the lake.

The only bright point in this potentially long wait is this general push for Mars colonization. As I said, determining if there is liquid water, with or without life, is quite an important step.
If there is sterile water that will reduce the price of the Mars colonization. If there is life, another issue will crop up. As I said, the potential Martians are most likely microbes. And if we are enough genetically similar, those might made us really ill. Meaning, potentially the whole plan of the Mars colonization will have to be either scrapped or severely modified to prevent not only the death of colonists but also the spread of microbes that might be returned to the Earth. Even if the microbes are benign for us humans, there are dangers of introducing them into the Earth's ecosystem. We are already aware of the problems that crop up when we transplant species into a new ecosystem. This is such a serious consideration that there is a talk about making a lab in orbit or on Moon that will deal with all possible samples we bring from other planets. But again, the price of such a lab is throwing a wrench into the gear.

So wherever the road leads us, it will be interesting. Unless we discover that there was an instrumental error, like with that faster-than-light neutrinos a few years ago.


No comments:

Post a Comment