Mars has right ingredients for present-day microbial life: study | Hacker News Reader

Mars has right ingredients for present-day microbial life: study

brown.edu

132 pointshhs119 comments

I know, it may sound absolutely irresponsible, but have the scientists considered practical benefits of sending in some bacterial life from Earth to let it try to colonize the remote destinations ahead of sending in humans for the same purpose?

Supposedly, micro-life has better chance to adapt to new environments, as long as the basic resource is available.

In case of Mars, humans lack the basic resources - water and oxygen. But could there be some bacterial life on Earth which could make use of the abundant carbon dioxide and could adapt to the harsh conditions?

Or such an approach would 'spoil' those worlds for the humans and take the conditions out of control?

More irresponsible than letting the human race exhaust and suffocate itself on this planet?

At some point we need to realise colonizing another planet is going to be necessary, and it is going to cause lots of damage.

we'll have exhausted this planet a thousand years before we'd have the technology to make Mars habitable. It just isn't going to happen for numerous reasons. The biggest are the lower gravity and the very weak magnetosphere.

We haven't even successfully made the deserts on Earth habitable yet without trucking in resources from more hospitable places.

Mars’ magnetosphere is something we could fix with known tech if we cared to. Expensive, but we could.

Lack of water, low atmosphere, they’re a bit further out of our range.

Fixing the lower level of sunlight is way out of our current league.

shading Venus from too much sunlight would be easier than fixing Mars' low level of sunlight.

We've only had much technology for a few hundred years. There's an argument that we should give it another few hundred to prepare a bit better. If we rush it, we might destroy valuable information or even forclose some opportunities.

But ultimately you're right. We will blunder our way onto Mars at some point.

We would never find out if life developed outside of earth.

And Jack and Jill won't contaminate space when they're sent to start Earth 2?

By the time we’re ready to even try that, we should have already answered the question, at least as far as whichever target you’re trying to colonise is concerned.

(And if you meant space itself, rather than the objects within, could reasonably be described as ‘contaminated’, then panspermia is both very likely how life got started on Earth and a reason to expect it everywhere else too).

Mars and Earth send surface rocks to each other via meteor impacts that would almost certainly contain live bacteria spores. Life could have started out on Earth or Mars or both, but finding life on Mars won't answer your question on its own.

There are even theories that life on Earth was seeding from life from other solar systems, but that is much more unlikely and an in solar system transfer.

Check out scholar.google.com and search for "exchange of bacteria between mars and earth" or other similar phrases.

I feel like the assertation that meteor impact ejecta would 'almost certainly' contain live bacteria spores and the implication that those spores would survive vacuum , radiation, heat cycling, and dessication for the very long trip from earth to mars is going to need a big old citation required here. That seems like a stretch.

Here is a very nice and through paper on the subject: "Natural Transfer of Viable Microbes in Space" https://doi.org/10.1006/icar.1999.6317

In the abstract: "The conclusion is that if microbes existed or exist on Mars, viable transfer to Earth is not only possible but also highly probable, due to microbes’ impressive resistance to the dangers of space transfer and to the dense traffic of billions of martian meteorites which have fallen on Earth since the dawn of our planetary system. Earth-to-Mars transfer is also possible but at a much lower frequency."

Life will optimize itself to fit harsh conditions at Mars, then return back to Earth, and outcompete original life forms.

Unlikely to be a concern. We have extremophile bacteria evolve here on Earth, they’re adapted to their specific niches rather than being all-around better.

Optimising for extreme conditions means being sub optimal for nice conditions so aside from taking over some volcanos we have little to fear.

Martian extremophiles are takin are jerbs!

There are even mysterious (with hypothetical biological origin) geysers on Mars: https://en.m.wikipedia.org/wiki/Geysers_on_Mars

To be perfectly honest they're not that mysterious. In the Martian science community they're called araneiforms, and the biological origin hypothesis is fairly fringe. Lots of good reading in these papers:

- "The formation of araneiforms by carbon dioxide venting and vigorous sublimation dynamics under martian atmospheric pressure": https://www.nature.com/articles/s41598-021-82763-7

- "HiRISE observations of gas sublimation-driven activity in Mars’ southern polar regions: III. Models of processes involving translucent ice": https://www.sciencedirect.com/science/article/pii/S001910350...

- "How martian araneiforms get their shapes: morphological analysis and diffusion-limited aggregation model for polar surface erosion": https://www.sciencedirect.com/science/article/pii/S001910351...

Curious, will the samples collected via mars return mission provide proof beyond doubt on this assertion?

That’s the hope! Though the rover should have most of the scientific equipment that it needs to run the relevant experiments right there on the surface of Mars.

As I understand, the samples collected by Perseverance and returned by Mars Sample Return will be taken at surface level. So they will not be able to tell that much about the sub-surface. Also of course that is just one small region that Percy is taking samples from, it can not provide proof about conditions of other regions of the planet.

What happens when we'd put some microbes there now?

We probably have done this already, with the man made machines that we had sent. Although the NASA tries to sterilize the robots/rovers, I doubt that they can kill every bacteria and some of the bacteria are known to somehow survive when exposed to space as well.

Earth bacteria require liquid water (amongst other things). Thus far none of the rovers have landed in a lake, so it's unlikely that earth bacteria will be spreading any time soon.

What's more important: knowing if Mars had/has life on it or having life on it?

I’m more concerned what happens when we bring some microbes from Mars.

things that go to mars tend to stay there

That's changing very soon.

Perseverance's mission includes collecting and storing samples for a return mission. https://en.wikipedia.org/wiki/Mars_sample-return_mission

And also things that have gone to Mars in the past have blasted off chunks of Mars into Earth.

Andromeda Strain makes a good story, but viruses and bacteria tend to evolve with their hosts and environment. It is unlikely that any virus or bacteria brought from mars would have a serious impact on humans or our environment. We probably aren't good hosts to something that's been evolving in martian conditions.

Interesting, maybe they plan to never bring anything to Earth's surface .. maybe use ISS as an 'air gap'

I've been curious about this recently actually. What are the downsides of "seeding" a plant with life to study how it evolves?

The fear I read is that we might be accidentally eradicating any life we don't yet know about, if we introduce life from earth.

Don't we already to this on Earth?

Yes, but it’s not helpful for research.

Means it’s hard to tell, if we find life there later, if that life was native or if we put it there.

It becomes much more difficult to determine whether the planet contains indigenous life once you've introduced life from Earth.

i think it's safe to assume it doesn't. And a few plants in a tiny section of mars will hardly ruin the evidence anyway.

What makes you think it’s safe to assume that Mars has no life?

a) simple maths; what are the chances?

b) we should have found something by now. There clearly isn't a whole lot happening on the surface of mars at any rate

a) nobody really knows the chances of abiogenesis or in-system panspermia yet.

b) we’re still guessing at bio-signatures; all we are confident of is there isn’t “a lot of stuff like us”, but that’s a compound claim and we can’t rule out “a small quantity of stuff like us” or “as much life as a desert but very different to us”.

I'm also a fan of this idea. It seems far easier than trying to plant humans in giant bubbles with an Earthly ecosystem that just happen to be on the surface of Mars.

As other commenters have noted, it's probably not very wise, but I imagine it would be the cheapest way to increase the chances of the continuation of life (as we know it).

But why would we want to continue life? Whenever I read something like that I feel life a sociopath but I don't really understand it. I'd care about the wellbeing of the people, not the continuation of the human species or, as here, of life itself.

I mean, I think it's kind of a natural reaction to "well if humanity disappears altogether, what was the point?", so we feel an urge to perpetuate humanity, in order to imbue our own existence with some sort of meaning.

Thank you for your answer. So maybe my lack of such an urge it's not about me being a sociopath or not, but a difference in philosophical views. Although gp was talking about perpetuating life itself, not humanity. Does knowing that a random organism somewhere far away it's keeping the metabolic torch lit satisfy this urge?

Maybe after initial terraforming you could also seed it with a specially engineered retrovirus to help evolution along by tweaking genes associated with prosociality.

Imagine if an alien lifeform had terraformed earth this way. We would not have existed.

(There is a hypothesis that life may have been introduced this way to earth, known as the Panspermia Hypothesis https://en.wikipedia.org/wiki/Panspermia)

There are so many chance events that could have gone differently and we would not have existed.

If not for an asteroid, the earth might still be populated with dinosaurs. Would they have evolved to our degree of intelligence and civilization? Who knows?

    The universe may
    be as great as they say,
    but it wouldn’t be missed
    if it didn’t exist.”

-Piet Hein

Evolution takes a long time. And there aren't many (any) environments that we've identified and can reach which are conducive to the sort of life we know about. Also it'd be a bit presumptuous for us to colonize a hospitable planet for our own experimentation.

But it's an interesting question. In fiction, I can recommend Adrian Tchaikovsky's Children of Time, and sequel Children of Ruin.

Both great books and a really interesting thought process on what truly alien life might be like instead of just humans with more or less arms.

And thank you as well

Thanks. Just picked up the first one on Audible!

Just finished reading the second, I really enjoyed them.

Evolved life will come back and may outcompete original life.

They’d die. For some reason the ‘beneath its surface’ part of the headline got left off this submission.

The surface of Mars is an anoxic toxic irradiated frozen desert.

Most likely we'd be able to determine they are from earth from their properties and from their locations and from their small numbers ?

There is a very good book on the origins of life on earth by Eric Smith, called "The Origin and Nature of Life on Earth."

Here's a YouTube talk with some of the arguments: https://www.youtube.com/watch?v=0cwvj0XBKlE

We don't have "full" understanding of human body and working of mind. I suspect in future humans who take birth and grow in different scenarios like earth natural / earth urban / mars urban and so on to have different life spans and body capacities.

I don't understand the excitement for finding life on Mars. I personally really, really hope we do not find life on Mars.

If we find even the most basic microbial life, NASA is going to shut down all future exploration in the interest of Martian planetary protection. China and Russia probably won't, but the US will cripple itself (again) out of caution.

On a more existential level, finding life elsewhere in the solar system (assuming it's not diaspora from earth or vice versa) says really dark things about our own potential. If life is truly common in the universe, the fact that we haven't seen it anywhere means that the great filter is still in front of us -- and nobody has slipped through.

OTOH, if the great filter is behind is, there's no data about our likelihood of killing ourselves before we do manage to explore the rest of the known universe. This is such a better outcome.

Alternatively both instances of life could be linked. https://www.space.com/22577-earth-life-from-mars-theory.html

That said my gut says hypothetically talking about the danger of a universal great filter is silly when we clearly face near term filters of our own design right now (climate change, environmental collapse, a nuclear arms race)

Massive loss of life or economic disruption, while hugely bad, is not what a great filter means in this context. If earth's climate returns to pre-holocene greenhouse gas levels, temperature and sea levels the human race would not be cut off from the stars in a fundamental way.

did you read Bostrom's article with the same opinion?

https://www.nickbostrom.com/extraterrestrial.pdf

first I've seen it but my initial thought is that he does not think probable as much as I do that a great filter may exist in the practicality of interstellar travel. if so, it's not a buzzkill to find pangolin skeletons on mars. we're all in this cul de sac together.

I think the excitement is that it would give us another data point for what life can possibly be like. So far (AFAIK) the best evidence is that life evolved once on earth, and so everything we see comes from that basic blue print. But does it have to be that way? Would alien life also be carbon based, or something else? Is DNA/RNA (or a close equivalent) a universal feature of life? If not what do they use instead? If so, that's also very interesting. There's just so many questions we can't answer when the sample size is one. I guess my belief (hope?) is that that curiosity would spur further exploration, not kill it.

As for the great filter, yeah, it's a bit scary if we rule out bio-genesis as an option, but that still leaves the single to multi cell jump behind us (and arguably development of human level cooperation/problem solving, but I'm less sold on that one).

Perhaps that would be a benefit, it could spur action to focus more and create L5 colonies faster.

The great filter is that tech is to easy, but self-awareness and self-discipline is hard. So life presses onwards, demanding exponential energy density from tech, to not be forced to limit itself and self-discipline itself.

Thus ever more potent tools are handed out to avoid confrontation with the "overcome" animal nature - and once that equation reaches the end of the line (easy energy and resources exhausted), a nearly unchanged animal with exponential power tools in hand, reverts to tribalistic warfare. Nothing recovers from this.

The greatest damage done, is the lie that life can learn and change, which never holds up under stress. The most valuable achievement to escape the filter, is investigate our nature realistically and apply controlled technological crippling, while testing the tools to calm the evil spirits of our nature, even under stress.

So technology is the problem and the solution, if applied with a real effort to understand humanity, beyond the "I wish for X and by the magic of wishful thinking it becomes reality instantly". Its hard work - similar to somebody diagnosing ones own mental limitations, and building a limited operating system for that crippled system. In a way- its the ultimate hack.

There could be civilizations out there that never developed aggression.

If they never developed aggression then they are not eating each other. Animals eat other animals because of the high concentration of nutrients in living things. Eating highly nutritious things allows an organism to develop both physically and mentally.

So they either have an abundant source of nutrients that has not been depleted for their entire evolution, or they are not highly developed, or they have developed aggression.

I agree, but plants are nasty too, just in slow motion.

For example some ficus grow over other trees, and later the roots cover the old tree until it dies. They don't eat the other tree, just "reuse" the wood to have an initial high place to get light. I coudn't find a nice link about this, but here are a few photos https://www.flickr.com/photos/rodolfocol/15129590163/in/phot... https://www.alamy.es/brasil-el-pantanal-parasito-higuera-fic...

Also, the eternal war between grass and forest comes to mind, the concept of fast, regenerative and self-destructive vs longterm investment killing the looping upstarts below.

Include in that the fire-economy of some forest and savannahs + the animals marshalled by these ecosystems and "peaceful" nature stops looking peaceful

http://akkartik.name/post/2012-11-21-07-09-03-soc

Billions of people were just asked to spend over a year locked down in isolation, and most did it voluntarily without reverting to tribalistic warfare (threats on fringe social media platforms notwithstanding). We've also in modern times seen what happens when famine strikes. Mostly people just suffer quietly and die.

Ah slight economic down-turn sparked a right-wing totalitarian resurgence across the whole world.

The lockdown mostly worked, because panem (food) and circensis (movie-streams and gaming) were continuously supplied. But, yes you have a point, the species behaved remarkably well under stress. But then, we also have a lot of social implants now too (cellphone-panopticon) and crowd-sourced anger-management.

Also its been half a year, since a angry crowd stampeded into the capitol building of a nuclear power.

Pretty confident we'd still explore, just with some (appropriate) care. Too many fascinating scientific questions to answer once we discover extraterrestrial life. And if Russia and China did, the US definitely would too --- what would be the point of standing on principal in that hypothetical?

Meanwhile if you're hoping, why not just hope directly that the Great Filter is behind us? It's totally plausible that the window for multicellular life to survive on a planet is generally short, like on Mars, and not long, like on Earth. Or a million other possible explanations that we also have no data for or against right now. I like to keep my science-related hopes on the side of the coolest possible result .

Personally, I don't believe in the great filter hypothesis. The universe is incredibly vast enough entire civilizations can likely go through millions of years of births and deaths without ever having contact with another alien life form. Humans have a huge bias to feel "special".

We've only been broadcasting radio waves for a few decades now, and even that would just be lost in the background noise at large distances.

It would be extremely surprising if we even find any life outside the solar system for at least a few centuries.

I don't think this gives appropriate weight to exponential growth.

If humans are ever able to leave the earth and even theoretically establish permanent habitation, it's unthinkable that no other civilization has done so.

Even so the galaxy (let alone the universe) is huge, and faster-than -light or extra-dimensional travel is probably impossible. Contact with another civilization is extremely unlikely even if life is abundant in the galaxy.

Check out von neumann automatons. The idea is that once you started colonizing, you'd cover the entire galaxy in ~a million years, aka very quickly on a galactic timescale.

https://en.m.wikipedia.org/wiki/Self-replicating_spacecraft

A galaxy is very tiny on the scale of the universe.

Sure, but the gp said galaxy.

the universe is huge and time is long, there could be millions of civilizations and we could happen to exist at a time that doesn’t coincide with a single one

The universe is extremely young. We might just be tied for first, if it takes 3rd generation stars for example.

I'm always on side of knowing than not knowing. Finding truly alien life would change society forever, maybe we would get more humble. As Carl Sagan put on Pale Blue Dot.

> China and Russia probably won't, but the US will cripple itself (again) out of caution.

Do you have any concrete examples when this happened before? Writing (again) implies you think there was already such a precedent.

If we do find life on other planets, I hope that it unites us more and we stop thinking in tribes of US, Russia and China and just work together as inhabitants of Earth.

It's strange that we have to speculate about if life could have emerged on Mars, without really knowing for sure how it emerged on Earth.

It's hard to learn something about a class of things while only studying one example of that class.

For almost half a century, scientists have been speculating about sub-surface life on mars. Why with existing technological progress can we not just get a yes or no answer about this.

If I had to guess: planets are big, rocks are hard, and if there is life, it’s vanishingly rare or hard to find.

Google something like “mars viking life experiments”

For a moment there I was thinking: "Wait, Vikings have been to Mars?", turns out NASA had a Viking program that sent two space probes to Mars in the 70s [0]

[0] https://en.wikipedia.org/wiki/Viking_lander_biological_exper...

I’ll answer your question with a question. Would space exploration get more or less funding if we settled a fundamental question about the existence of life outside earth?

Probably more.

I would think they would get way more money to look at that life.

Because determining a yes or no answer requires running tests and examinations of Martian subsurface soil samples on Earth.

Part of Perseverance's mission is to take those soil samples and deposit them to be picked up and brought back to Earth on another later mission.

https://mars.nasa.gov/mars2020/spacecraft/rover/sample-handl...

That seems highly unlikely to ever happen unfortunately. Any mission able to land and take off from the surface of Mars for a return trip is likely going to be able to take its own soil samples

A later mission doesn't have to focus resources on scouting sites of potential interest, drilling, testing, analysis and sample storage. It can focus on picking up its cargo and getting back to Earth, which would be an amazing feat by itself.

Thats a good point. I hope that would be enough to get funding. It was certainly a good idea to collect the samples even if they dont make it back to Earth anytime soon.

Several experiments have already been carried out, but none have been able to fully prove or refute the existence of life on mars. There is still room for more evidence and precision, but most likely there is no life there.

As soon as the habitation of Mars picks up a little momentum, martians and Mars colonization will be demonized by the media. It will become a political debate that is fueled by the CIA and other entrenched interests. They will paint it as an ethical issue and focus on the immorality of disturbing the native habitat, or something similar to that. Mark my words.

The ethical issues with colonizing/developing Mars were already explored pretty deeply in Red/Blue Mars almost 30 years ago, so readers could mark Kim Stanley Robinson's words instead

The substance of the issues will not be of any importance. They will be used as a tool to alter the course of Mars colonization. Just like every other topic of geopolitical importance, it will be distorted by special interests in a hell-storm of irrational dogma. And just as always, people will lap it up and the truth will die a brutal death. The amazing thing is that it hasn’t started yet. People in the government don’t understand what’s going on. But eventually they will catch on.

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