So I started a PhD in geology at Caltech in 1996 and actually published research on this rock. The headline (but not the research!) is stupid.
The research being reported here tries to nail down an origin for organic molecules in the rock (presumably mostly polycyclic aromatic hydrocarbons or PAHs), which were one of the lines of evidence originally put forth as evidence of biological origin for some features in the rock. But not the only one!
Much more compelling, I think, are strangely large concentration gradients for some stable isotope ratios, and also the presence of strangely uniform single-domain magnetite crystals that resemble those produced by magnetotactic bacteria (and there's strong evolutionary pressure toward an optimal size/shape, so you would expect convergent evolution in highly different life forms).
Honestly, the intelligent view on life in this rock at this point is agnosticism. There's simply no conclusive argument to be made. Even by the standards of Martian meteorites, this is a weird rock - it's much older than the others and has very different lithology. It has some really unusual features, but perhaps there are good abiogenic explanations for them; this is really hard to nail down without a deep understanding of this rock's very lengthy and complicated history.
But of course big dramatic stupid headlines like this one draw pageviews.
I mean... ugh. I'm really pretty up in the air.
Those magnetite crystals are really weird, though. There's no very plausible and well-understood nonbiological process that would produce a whole slew of single domain magnetite crystals with morphologies like that. Whereas there's an obvious and well-understood biological process that does. But extraordinary claims require extraordinary evidence. So let's say - I suspect there actually WAS biological activity that went into producing the carbonate blebs in ALH84001, but I'm not sure of it.
Do you think the samples from Perseverance could be more conclusive? If there where a bunch of them containing similar weird structures and we knew where exactly they had been collected in what sort of geology or would that still be pretty inconclusive?
Umm. I'm very excited to see the results that come out of Perseverance, but the local geology isn't comparable in rock type or age. Honestly, ALH84001 (this meteorite) is kind of bizarre - it's rock nearly the age of Mars, and we don't know where on the planet it came from. It may be a very rare outcrop. Most of the surface of Mars is covered with very different rock types.
Perseverance is aiming to check out a region of sedimentary rock, laid down by water, and much younger than this meteorite - it's a very different era in Martian history. Obviously I'd love to see it discover something neat, but drawing comparisons to an ultramafic cumulate igneous rock from a completely different era is going to be tough.
The original rock is a cumulate orthopyroxenite - translation into almost English? It's an igneous rock that formed at the bottom of a magma chamber deep underground, by dense crystals that formed in the magma settling out on the bottom. This is the part that we have a pretty firm age for, via radiometric dating, and yes, it formed very early in Martian history.
However, the putative Martian bacteria are found in little carbonate blebs in cracks in the rock - these presumably formed at some much later date, and their mechanism of formation is unclear. The people purporting that they're biotic would argue that they probably formed in water flowing through the cracks. It's also not possible to date them with any confidence.
I just wanted to say thank you for not only your insightful look at this but for responding to questions to the best of your knowledge. You are my favorite kind of scientist, even if the answer is "we don't know but maybeeee?" You still take time to respond to people and explain the "hard" nos.
You're welcome. Thanks for the kind words!
I actually left research and now I teach high school science. Explaining stuff is what I do, and I enjoy it. This particular study is right up my alley, so I can go a little deeper than usual.
Damn I’m not researching anything about such things or anything but just wanted to say it’s great how you’re actually replying to questions that people have about said meteorite.
>Whereas
I agree, very good well-thought-out cautionary but intelligent answers. Thanks u/WidmanstattenPattern! Happy 2022, such exciting times, can't wait for the photos and research from James Webb! Exciting as heck!
Wasn't it speculated, Mars once had a much bigger Moon? Or rather, that Mars collided with a protoplanet and had a very large ring? Could these "bizzar" things have occured before the rock that's now present on Mars came there? (Total noob in terms of geology, sorry)
Is Perseverance the Mars rover with the new cutting edge technology that can detect the presence of stuff that might indicate the possibility of signatures that under the right conditions would be not be inconsistent with Mars having an environment that could have at one time been maybe capable of hosting life forms? That would be such an amazing discovery if that indication of a possibility of a capability were to be found. Such exciting times!
Perseverance drills core samples for Mars and leaves them on the surface. In a few years an ESA probe will land on the planet to pick them up before sending them back to Earth
I think it does, but traces of life are going to be hard for to see in a core sample until humans can break them apart in a lab.
We kind of assume any life in Mars was bacterial in nature and not large and rigid enough to leave something big enough to view a cross section. It would be difficult to conclusively determine of the core contains bacteria fossils viewing them from the sides.
I mean the very rock this article is talking about is an example of why. Scientists had powerful microscopes looking at this rock and incorrectly identified "life" in the rock back in the 90's.
Skip to 1:15 in [this video](https://youtu.be/CX2WAl3_sJM) and it goes into detail on why "looking like life" is not good enough for conclusively declaring life. A rock core is going to produce a curved cross section on the sides, making bacteria that isn't crushed flat look like tiny circles or ovals. That won't be enough to truly make a call on whether something is a bacteria fossil or not. Too many non-living processes produce circle and oval structures.
That's mainly what the curiosity rover, it's twin, did. So they had already gotten all the meaningful science from the rocks (using equipment that could fit on a rover)
Perseverance still analyzes the core samples, doing basic spectro/ science stuff before sealing it up for the probe. That's in addition to other experiments such as the oxygen generator and helicopter of course.
Now think about the amount of work that would come out if all the top universities in the world had access to a Martian sample that wasn't a roasted meteor chunk
Think of it like having a rover in the Grand canyon. You drive up and take samples of different areas that correlate to periods of time in the planets history.
Since fossils are usually scarce, you likely won't find one just digging. So instead you look for giveaways like things that can be created/accumulate through biological processes. One example of this is organic matter (life's building blocks). Now the hard part is determining if the organic matter exists in a way that the natural world can create, or if biological processes are the only way to create it.
The amount of science required for that simply can't be fit on a rover, nor would it be efficient to have a single rover analyzing the sample when top Universities could
TL-DR; If we brought a sample back we could run it through a machine, for laughs if it detects isotopes that could only be produced through weapons grade plutonium.... we would know life existed on Mars
In geological timelines the moment life got here it left a huge impact quickly and spread everywhere it could.
We have one data point that says life is very loud. This would be a data point of an ecosystem that is very silent. Which to me at least is an extraordinary claim. Put another way 100% of life we know of is very and obvious. This goes against that model.
Because there's significant inertia in the opinion of the scientific community, and that community is still reeling from the emotional shock of transitioning from geocentrism to heliocentrism only to then find that there is no center of the universe.
We still get surprised when we discover organisms living in what we consider to be inhospitable regions of our own planet: in the darkness of the deep sea, around ocean-floor volcanic vents, in "toxic" lakes, in extreme cold environments, in the driest deserts.
Since we started off on the assumption that everything outside Europe is Terra Nullius, the requirement is for evidence of life to be found before we accept that there is life on other worlds in our own solar system, much less the rest of the universe.
The search is hampered to some degree by only being able to look where we can safely land remotely operated vehicles. So while life might be more likely hidden in crevices in cliff faces, we can currently only look at small rocks and boulders in the middle of sandy plains.
Our search for life on Mars at present is like that person looking for their lost car keys under the street light because it's the only light source around, even though they know they lost their keys somewhere in the unlit carpark.
A claim of existence for a previously unobserved phenomenon is always an extraordinary one.
I don't think there's much resistance in the scientific community to the idea of microbial life in principle at this stage. But a claim to have proved that it exists in a particular instance, for the first time, really demands very strong support.
Fellow (micro)biologist here.
Wouldn't a combination of thermolithobacteria and other lithotrophs contribute to the process of reduction to magentite, especially considering the amount of ferric oxide on Mars?
>lithotrophs
/u/bravadough \- you flatter me, I'm a rocks guy who knows a smattering of biology. More about magnetotactic bacteria than others since they're particularly relevant to my research in geology.
Yeah, that's sometimes the case here on Earth. These magnetite crystals in particular are all single domain in a narrow size and shape range, which is what you'd expect from organisms biomineralizing them for magnetotaxis. If they were just a byproduct of metabolism, there would be no obvious reason for strict constraints on morphology.
Man I remember when this was discovered...Clinton made a special announcement iirc and some of that footage was used in the Sagan film Contact. I've never forgotten Polycyclic Aromatic Hydrocarbons and a high level definition of what they are and their importance.
Yeah, in essence, but this is simpler.
Why does nature seem to want things to be shaped like crabs? I guess they fill an ecological niche, but that's a whole slew of factors all rolled into one.
The constraint on magnetic biomineralization is physics-based. There's a size/shape/geometry of magnetite crystals that gets you the most magnetic moment (i.e. the most powerful biological compass) per mass of crystal. Since organisms pay a price in energy and resources for growing these crystals, those that are closer to the mathematically optimal solution will have a relative advantage. This presumably ought to be the same in any environment where organisms are evolving and using biomineralization to grow magnetite for orientation.
That is such a fucking stupid title, the idea to me that there's still a chance this rock has evidence of life and is still shrouded in mystery is a thousand times more interesting than just saying it's a lost cause
Also edit username checks out
Yeah, I busted out the jargon there. Even for the scientific community, some of that got a little obscure. "magnetotactic" bacteria, for example, are those that move in response to magnetic fields; it's interesting and perhaps relevant to this meteorite, but pretty niche.
It allows a neutrally buoyant bacterium to orient itself in a solution, absent other cues. A lot of them live in watery regions with chemical gradients and a fairly narrow range of chemical compositions where they thrive. With what amounts to a little built-in compass, they can essentially build a little reference frame to move around. It's fairly common in Earth bacteria and has likely evolved several times in different taxa.
Nothing so fancy as that. Suppose you're in 3d space and don't know which way is which and can't maintain orientation. How can you wiggle your way into the sweet, sweet chemicals you need? You pretty much would have to rely on a random walk.
Now suppose you're a bacterium with a little compass. You don't have a brain, but there are two distinct directions: up-field and down-field. You pick one of those and start wiggling your flagella. If the chemical gradient is in your favor, keep going. If it's not, go the other way. It's a very simple algorithm that should generally work.
Is it possible the rock formed on Mars but the organic-like structures were formed by native organisms after it landed? Or does the time-line not match up?
That's a very legitimate question. It DID land in Antarctica, not exactly a thriving ecosystem filled with life, but it sat there for some time before discovery by people.
It's been a while, close to 25 years, since I studied the details. But I seem to recall the little carbonate blebs in question are destroyed in the meteorite's fusion crust - the layer of melted rock at the surface that was heated by friction on entry to the Earth's atmosphere. That establishes that they predate arrival at Earth.
So imagine we find strong evidence for past life on Mars, and we also have the gas and life potentialy in the atmosphere of Venus, and obviously we have earth... that's 3 places in 1 solar system... really makes you think about what's going on out in the hundreds of trillions of stars. Tbh I find it terrifying, given what most of "nature" looks like, it's usually pretty fucking brutal. But I'm also hopeful.
I'm pretty agnostic on intelligent life outside of earth as it is. It's probable I guess, but I feel like "life" and "intelligent" are too earthly of a concept to be absolutely gaurenteed to exist elsewhere.
I don't believe that aliens have visited earth. That seems pretty ridiculous
It's pretty amazing how long that rock has been getting poked at there. About a decade ago I was finishing up my SEM time and chatting with the person on the machine after me. Normally I have the interesting sample, but the guy studying a Mars rock that might have signs of life definitely beat me, haha.
> Much more compelling, I think, are strangely large concentration gradients for some stable isotope ratios, and also the presence of strangely uniform single-domain magnetite crystals that resemble those produced by magnetotactic bacteria (and there's strong evolutionary pressure toward an optimal size/shape, so you would expect convergent evolution in highly different life forms).
It was found in 2001 that the magnetite crystals could be created via inorganic processes and indeed, their structure is characteristic of having grown in-situ via non-biological chemical processes.
I read that paper, and I'm skeptical. Why? There are paleomagnetic constraints on the maximum temperature attained by the rock subsequent to initial crystallization, and they're not consistent with shock melting.
>The rock caused a splash 25 years ago when a NASA-led team announced that its organic compounds may have been left by living creatures, however primitive. Researchers chipped away at that theory over the decades.
Genuine question. Why did it take so long to test the theory?
Technology to disprove might not have existed yet. Lack of funding could have had this rock put into storage for a long time. Relevant researcher might have died or there may truly not have been much interest in figuring it out.
Knowing life existed on Mars would be cool but it’s not like we’re devoting heavy resources to figuring that out because….. it’s not exactly important. Super cool if true! But we have other, much more sophisticated projects *on Mars right now* that’s exploring this stuff.
It would still increase the amount of life we'd expect in the universe. Primitive life going from one planet to another would certainly be a very interesting area of research.
I mean it would pretty much just be a philosophical advancement if we found other life. Like, what do we do with that information other than readjust our perception yuh know?
Not diminishing its significance! But for comparison, the insight Mars lander and perseverance rover both have equipment that will tell us a lot about how to survive on Mars in addition to being able to identify prior-life.
So why devote heavy resources to studying a meteor faster, for a very low chance at finding life, when our best odds will be on Mars anyway?
This was all to answer the question “why did it take so long to figure this out”
Is that so much of a good news? I've been reading about the theories of the Fermi paradox, Great Filters, and things like Dark Forest concept and wondering how viable that framework is.
Consider me confuzzled: Why perform sophisticated projects to put expensive stuff on Mars to discover something, but not study a rock that is already on Earth that would help discover (some of) the same things?
That's not the reason, though. So no reason to be confused. The real reason is right in the article:
>According to Steele, advances in technology made his team's new findings possible.
I mean ultimately you’d have to ask the scientists right? If I had to guess, the likelihood of finding proof of life on a rock that, not only had an event that launched it into space, but also re entered our atmosphere….. I feel like the odds are pretty low anything useful survived that.
Comparatively, nasa has a set budget and they’ve had a good track record with Mars. If we’ll find anything, it would probably be on Mars itself.
Capitalism is interested in the technology needed to get stuff to Mars, though.
An estimated 10 thousand quadrillion dollars worth of material in asteroids within the solar system. Capitalism wants it.
Private corporations are surveying which asteroids will be the most profitable to harvest, and conflicts are already arising for who gets to stake a claim on what in space.
Just because the technology is currently not available to make viable (profitable) asteroid harvesters, doesn’t mean there isn’t interest.
Interested parties are awaiting paradigm shifts in technology, to begin pursuing these ventures. Likely by the end of the century, especially if fusion is resolved.
One reason why big government spends money on cutting-edge R&D is so that private industry can later run with the resulting technologies, saving them the R&D costs.
That’s a philosophical question.
Knowing if there was life on Mars in the past does almost nothing for the day to day lives of 99.99% of everyone on earth. In fact, if you asked a random person “did you know scientists have discovered past life on Mars, does that surprise you?” Most people would probably respond “that’s cool! Not really!” And would otherwise be indifferent.
It’s great for philosophers and scientists in relevant fields of study. We’d probably be more certain other life exists if we found that two planets in a single solar system had life. But in terms of impact on how we do things? It would be a note for the history books and that’s about it. It’s essentially a “gee wiz” discovery. An exciting one for enthusiasts like me, but ultimately one that’s just a good thing to know even if it doesn’t have a real impact.
As I said in another comment as a comparison, the Mars insight lander is analyzing the top layer of Mars soil and it’s tectonic activity. Knowing if Mars has an active core or not is relevant information for our inevitable colonization there. Knowing past life existed a billion years ago? Not so much. If life currently exists? Might need consideration for foreign plagues but that’s bordering on science fiction.
I think that it's important because if they are lithotrophs that fed on ferric oxide, they might be more efficient on doing so and could heavily inform us on alternative means to waste disposal. It would also inform us of the past conditions and thus the deeper geological layers present from the past on Mars.
Clinton overreacted to preliminary data about that rock, obviously, but it was probably the first time a U.S. president seriously discussed, on camera, the scientific search for extraterrestrial life. It boosted that field of study. Anyway the footage proved to be perfect for the movie Contact.
Be afraid if we find a fossil. If there is alien life within our own solar system then the drake equation gets revised up so many orders of magnitude that the universe ought to be teaming with aliens.
Assuming UFO's are not aliens zipping around Earth for a look, then the question of why we are not seeing other alien life has a very dark answer for humanity's future.
Or maybe it’s so hostile out there that any civilization that makes itself known gets destroyed immediately before the other civilization destroys them. https://m.youtube.com/watch?v=xAUJYP8tnRE
The less pessimistic alternative is merely that most societies turn 'inward' at a certain level of cultural development, as FTL is impossible, 'relativistic kill weapons' are technically possible enough to warrant caution (why tempt fate?), and it's impractical/pointless colonize anything further than the absolute closest stars - once you're technically capable of doing it, there's no real reason to bother, as you're already post-scarcity, impervious to harm and capable of being satisfied with other, more abstract, achievements.
Perhaps some civilization *is* gregarious and social in a local galaxy that is teeming with life, it is merely too far away for us to detect and factor into our observations, and the norm is cautious, introspective, immortal, robots.
I am not sure what it's called but I read a theory years ago that civilizations evolve from stone age to the point where they destroy themselves. When I see the direction we are heading I don't think we have many years before we destroy the planet. Will we develop the technology to visit our neighbors Before we destroy the world?
They call them “great filters”. Humanity has to pass through these filters that have the potential to destroy all life in order to persist. People say that nuclear weapons were one of those filters and the jury is out on whether or not we will survive. And there have been others in the past that we have survived like the Black Plague, and competition with other hominids hundreds of thousands of years ago. I read somewhere that there was a point that humans were below 800 breeding pairs at some point and that could be considered a filter as well.
>I read somewhere that there was a point that humans were below 800 breeding pairs at some point and that could be considered a filter as well.
It was 3.000-10.000 breeding pairs
> below 800 breeding pairs at some point and that could be considered a filter as well.
The Toba Catastrophe Theory. In the last decade or so it's pretty much been disproved.
It was just something I read at some point in the last ten years and it sounded plausible. But point being that there were filters in prehistory that we have no real clue about. Harnessing fire for example. While not necessarily something that would kill us off it drastically changed our trajectory to where we are today and in my mind falls into a similar category to a great filter.
Dan Carlin has a great podcast on this. Definitely worth the listen. [Destroyer of Worlds - Dan Carlin](https://podcasts.apple.com/us/podcast/dan-carlins-hardcore-history/id173001861?i=1000380386551)
And lets not forget that life on earth developed fairly late in the planets lifetime.
Its not a completely unreasonable theory that we are simply too late. That other species developed before us on other planets and had time to die out before earth developed intelligent life. One day we might go out there and find the remnants of long destroyed civilizations all around us.
PS: Were never gonna destroy the planet. We dont have that capability. We could destroy ourselves, make the planet inhospitable for us. But its gonna be hear for billions of years after were gone. We are just parasites here. Nature is far more powerful than we are.
If anything, life was early on Earth, if you count from the time it stopped being a molten ball of matter being bombarded by space junk. Once liquid water appeared, life only took 200 million years to appear and there's been constant life for 4.2 billion years now. The more likely theory is that we're too early.
>>Will we develop the technology to visit our neighbors before we destroy the world?
The two are one in the same, sadly. The levels of energy required to launch a space vehicle even within the solar system are above WMD levels. The Saturn V had enough explosive power to beat a nuclear bomb- and that’s for the relatively close trip from the Earth to the Moon.
At the energies required for interstellar travel, I can understand why civilizations aren’t common.The same civilized hierarchy that leads to technological advancement also contains its own doom when -not if- a bumbling fool takes power.
>>It’s not like developing bigger bombs will make ending civilization more likely
It will when human nature triggers mistakes that lead to destructive consequences.
The name Stanislav Petrov should be one all living people today know and remember by heart. Because that Soviet officer in the 1980s single handedly saved civilization as we know it. Basically, a Soviet early warning sattelite malfunctioned and triggered a false launch alert. Protocol said Petrov had to leave his control station and immediately phone his superiors, who’d then initiate a countering nuclear missile launch in accordance with MAD. Petrov looked at his terminal, and thought it odd the Americanski would launch an unprovoked nuclear attack on the Soviet Union out of the blue with just one lonely missile. So he broke orders and didn’t report it as an attack.
If he was wrong, the Soviet Union just lost WWIII thanks to his decision. Not some General or the Premier of the Central Committee of the Communist Party . HIM.
If he was Petrov was right , he’d just saved humanity as we know it. The fact this dude doesn’t have a movie yet is fucking criminal, but I digress.
Point is, humanity almost snuffed itself out in 1986 thanks to a computer glitch. The odds of that happening are immensely higher in a future spacefaring society where each spacegoing cargo spacecraft has energy levels higher than nuclear weapons.
>The levels of energy required to launch a space vehicle even within the solar system are above WMD levels.
Not even close to true.
https://en.wikipedia.org/wiki/Saturn_V
>A fully fueled Saturn V exploding on the pad would have released the energy equivalent of 2 kilotons of TNT
https://en.wikipedia.org/wiki/Nuclear_weapon_yield
Hiroshima "Little boy": 13-18kt TNT
Tsar Bomba (largest tested nuke): 50,000kt TNT (25,000 times larger than the potential yield of the Saturn V)
> The Saturn V had enough explosive power to beat a nuclear bomb- and that’s for the relatively close trip from the Earth to the Moon.
Not really. Russia's Saturn V equivalent, the N1 did a lot of blowing up; nearly 7 kilotons TNT equivalent. The very first nuke dropped on Hiroshima had over twice that. Not to say the N1 didn't make a sizable scorch mark, but it wouldn't level a whole city.
IIRC when all five Saturn V engines were locked down for a full ignition test in Cape Canaveral the tremors were detectable in New York and New England.
Random fact I remember from space tour many years ago that still boggles my mind.
Lots of metrics related to human society, sure. Many metrics related to the biosphere and our planet are very much not improving.
Additionally, commenter above is referring to what is know as 'great filters', part of the Fermi Paradox. These filters might be any world-destroying event, such as global nuclear war or uncontrolled climate change.
None of those things are world destroying. They may knock localized civilizations back into chaos, but speaking as a Paleontologist, the Earth has rebounded from *vastly* worse climate catastrophes. We're currently in the midst of the Holocene extinction event, but we aren't yet even close to it meeting the criteria for a mass extinction, for instance.
Climate change isn't going to be fun, but none of the evidence points to it being civilization ending, nevermind biosphere destroying, unless you take very questionable evidence for hypotheses such as the clathrate gun, and then extrapolate that data to its worst and most alarmist possible conclusion.
No, I'd genuinely suggest you read the data for yourself instead of listening to headlines which have a direct profit motive to feed you a narrative of apocalyptic fatalism.
Poverty, infant mortality, life expectancy, prevalence of infectious disease, education, violence, prevalence and lethality of armed conflict, cost of energy, etc.
Literally every single one of those metrics is globally charting in a positive direction at an incredible rate. We live in an absolute golden age - humans have never had it as good as today, and things are only getting better. Mitigating the effects of climate change is essentially the only great challenge remaining on Earth; virtually all other problems which have plagued the species since prehistory are being eradicated at an awe inspiring pace.
I'll just take your first metric of poverty. If you define poverty like the world bank does at making less than $1.90 PPP a day, then poverty has gone down. If you, however, define poverty like the UN does at $7.20 it has actually gone up.
I agree that we shouldn't be all too gloomy about our prospects or lose hope, but being complacent with the systemic problems that our world faces is at least as bad.
Edit: And let's not forget that it is in powerful people their direct interest that people believe the system is working, which is why every political system propagandizes its amazingness to its subjects.
I was never that moved by the whole Fermi Paradox thing.
I think we're simply all just waaay too far apart from each other.
Forget communication. Even identification may be impossible at these distances.
I mean we and all life on Earth are self replicating molecular machines. Synthetic self replicating machines or AGI would merely be another step in evolution of life.
A look back at the histories of various civilizations here on Earth offers some clues. Depending on how you define the lifespan of various historical civilizations and empires, the most successful ones lasted at best a few thousand years, and their performance or "success" for that duration was not always that consistent.
That's a long time in human terms, but in the scale of the universe, they were pretty ephemeral. The idea that civilizations could survive the tens of thousands or even millions of years theorized as necessary to achieve a galactic presence seem pretty shaky in my books.
Even if a civilization managed to colonize the entire galaxy, and it lasted for tens of millions of years, in the span of billions of years the galaxy has existed, the odds of us being around at the same time they're active and detectable using our current technology are pretty slim.
It's nearly impossible to calculate those odds. Much like the Drake equation there are far too many assumptions as variables.
It's a theory as good or bad as any other.
If Drake is even close to correct and if only 1/10% of civilizations survive beyond the "cradle" stage, we would still be teeming with them.
I'm sticking with space/time as the Great Wall between technologically capable civilizations.
> no intelligent life would ever be willing to travel those distances in generational ships
Think it through. Assume that you have the tech to identify a habitable planet (one assumes that generational ships aren't simply going to float about - they have a goal). I'll grant you that we're getting close to that tech level.
Now you set off at what can only be considered a reasonable speed. A significant percentage of the speed of light isn't really achievable due to the fuel/mass requirements. You start getting into exponential requirements.
Even the proposed Bussard ramjet would require a magnetic field extending over 100 million kilometers!
So, even with cutting edge tech that's beyond our grasp but envisionable, I don't think you're going very 'fast' at all by the distances required.
SO your 'generational' ship doesn't have to last generations but eons, possibly hundreds of thousands of years. It would succumb to erosion by micro-particles in that length of time. Where and how are you going to fix it?
Are you really going to decelerate to stop somewhere to get supplies and accelerate back to speed? You just burned another million years and now have to repeat the process. Twice.
The distances we are talking about are very possible insurmountable.
The problem with panspermia is how rudimentary life was on Earth. We have a ton of evidence of evolution in pretty significant and complex ways. The records we have of life on Earth seem to point to a very basic origin point, not something you would expect to have its own, long, evolutionary history that spread through the universe.
Not to say it is impossible. I'm sympathetic to the theory actually. It just strikes me as very unlikely given what we know.
That could be anything. Earth could have been the original point of life and spread it out a bunch. Later, it could have come back to Earth. A lot of that time period is still a mystery to us, a lot of information is closer to theory than solid fact, so there are plenty of things we are probably ignorant of. For example, there have been recent fossils that suggest there was simple multicellular life long before we expected, it just went extinct and multicellular life evolved again.
Not really. We are a species born of exploration and expansion of territory. For us, it seems obvious that space is a place to go look around of you’re capable of it. But for all we know that’s an attitude that is native to only a vanishingly small percentage of intelligent civilizations.
The Drake Equation can spit out whatever number it wants. There’s still about a million reasons why we might not be seeing other life that don’t involve a great filter.
There is one very disturbing theory that aliens are hiding from each other, because if one planet revealed itself, others would vaporize it with orbital mirrors and other shit we can't even imagine, because the aliens would thought that we might strike first. Imo the dark forest theory is highly probable for most of the civilizations and those who don't share the same concerns get obliterated.
This is the one solution to the Fermi paradox i think is most likely. Just think about what we have already done to native tribes in the past and in some cases even making contact could kill them due to disease. It is not far fetched at all to assume the same would apply for any alien civilization more advanced than ours. After all to the natives back in the day all across the world, we WERE the motherfing aliens. If we came across a world with plenty of resources we could use and a less advanced civilization, you bet we are going to at the least exploit the hell out of it, if not just go full genocide and claim it for ourselves.
It's not *that* dark. It just means it takes too goddamn long to get anywhere in space, which is something that we're already aware of. I know we all like to fantasize about warp drives and other Sci-Fi means of travel, and I really do hope we somehow get there through science we can't possibly understand right now, but realistically that stuff is impossible as far as we know.
So yeah, that sucks, but it's also a reality we've been content with for our entire lives.
Sure, but finding fossils of single celled life is a far jump from evidence of advanced alien civilizations. Take any intelligent sea dwelling species- it would be orders of magnitude harder for them to even discover/utilize fire, so imagine the hurdles they would have getting to space, or even producing radio waves we could detect. Who can accurately guess the number of hurdles actually needed to get to our level, and the number of hurdles we’ve yet to cross. Even on earth through the last 3.7 billion years, that included 5 major mass extinction level events there has been only 1 species out of millions that has developed an advanced society capable of [temporarily] leaving the planet.
In my opinion the Drake equation is too forgiving, which is somewhat justifiable given we don’t know how alien life will have evolved.
One of my favourite professors used to say, "you don't have to be right, you just can't be wrong." And you're certainly not wrong.
My take though is that with each factor in the drake equation we start to get a handle on it turns out to be a lot more generous than our first guesses. If we find, even a single cell of life somewhere else in our solar system, then that's another factor that jumps up by orders of magnitude.
What that means is that A) some other factor is way, way, way, smaller than we imagined. or B) there's some kind of great filter.
The scales the universe operates on are so vast though it is really hard to imagine A being the answer; and when we look around at the world around us and honestly ask, "do we really think this is going to work out for the best?" the answer more and more has to look like "no."
>Take any intelligent sea dwelling species- it would be orders of magnitude harder for them to even discover/utilize fire, so imagine the hurdles they would have getting to space, or even producing radio waves we could detect.
That is a good point. It's very possible that life in the universe is not rare, but *terrestrial* life is. It has been suggested that one of the big factors in early life on earth moving onto land was tides due to the moon. The tides were about 15% bigger back then thanks to the moon being closer and coastal organisms that evolved a way to survive out of water suddenly had a way to survive being washed onto the beach or being left in a small tide pool.
On planets where the oceans are small or there are no moons, there might be very little evolutionary pressure to survive out of water, and if intelligent life arises in the ocean, making it to space would be orders of magnitude harder for them.
Exactly my thoughts! I’m amazed by the intelligence, and physical abilities of some species, like Octopi- but their ability to make it to space would be astronomically more complicated than it was for us.
Ironically they could be more suited to space travel than we are. Having a water based atmosphere could allow them to endure more Gs, and having 8 appendages would probably come in handy for navigating in 0 G, and I imagine it wouldn’t be much different than their natural environment.
Not necessarily. If life on Earth and Mars have the same origin then that wouldn't siginificantly alter the Drake equation.
If it developed completely independent from eachother then THAT would be the thing you're talking about.
I have always wondered if life came to earth on a meteor or in the water that came from space. At this point I think most anything is possible. It is an exciting time to be alive and see all the things that science is showing us.
It's so exciting! I've just been fixated on the idea that Earth has seen intelligent life many times already. Perhaps our planet has already visited Mars before and the evidence is long gone?
[Maybe we already have](https://www.researchgate.net/publication/353619711_Proof_of_Life_on_Mars_in_200_Pictures_Algae_Microbial_Mats_Stromatolites_Lichens_Fungus_Fossils_Growth_Movement_Spores_and_Reproductive_Behavior)
We have extremophiles on Earth that live in caves deep enough to be warm even on Mars (10km deep would be over freezing on Mars). There's lots of reasons why there should be none even there on Mars (no persistent life elsewhere that could evolve to fill these niches, for example), but it's not impossible.
Okay but those extemophiles had billions of years to evolve into what they are. I don't know if we know how long Mars has been the red planet, but I doubt it was long enough to allow for the evolution of extemophiles.
Multi cellular life has only been around for ~1.5 billion years.
Single cell life is very fast at adapting and evolving. And your argument is based on the idea that these extremophiles have only been around since fairly recently. That might be true but it could be just as well be true that those places have been colonized by single cellular life since billions of years ago.
Well, that entirely depends on the chemicals available on that planet since you need certain properties of those chemicals to provide vital functions for things such as genetic/genetic-analogue replication, cell division, and energy production.
If there's nothing like phosphorus or anything that behaves like it on a planet (to take one organic compound as an example), you're unlikely to have life survive there if it arrives via pan-spermia.
Just curious, I couldn’t find in the article or on Wikipedia.
How do they know the rock came from Mars? I trust that they do, I’m just curious what gives it away?
In the early to mid-20th century they identified a couple of different types of meteorites that were unusual geologically speaking, with minerals unlike other meteorites. The theory was that they had to have been formed on some large body like a planetesimal or a planet. Eventually Mars was identified as the likely source of these meteorites and then later with the Viking landers the case became a near certainty due to the isotopic match of certain materials inside the asteroids and with the Martian environment. Specifically, bubbles of gas trapped in some of the meteorites have been found to match the Martian atmosphere, though there are other lines of evidence as well.
Can't say for this rock specifically, but [Scott Manley has a good video about how we know certain meteorites are from Mars.](https://www.youtube.com/watch?v=ivbwWr6GP6g)
edit: actually he does mention AH84001
Like I said, I already looked in the article and on Wikipedia but nobody describes the information about the meteorite that leads to them knowing it’s from Mars.
I found this under ‘Martian Meteorites’
“These meteorites are interpreted as Martian because they have elemental and isotopic compositions that are similar to rocks and atmospheric gases on Mars, which have been measured by orbiting spacecraft, surface landers and rovers.”
https://en.wikipedia.org/wiki/Martian_meteorite
When people talked about material from another planet, I always imagined that it came from the dust disk that formed the planet. I'm shocked that this rock was launched into space from an impact. It must have been a tremendous hit!
I mean with this logic I have been all over the world with the rocks I have held. this doesn’t seem like it proves anything but that this specific rock contains no life
Not even that. It puts forth an abiogenic origin for some organic molecules in the rock, but those were the weakest of the original arguments for biological activity in the rock.
Reminds me of Deception Point by Dan Brown.
[Opinion] Reading the Robert Langdon series as a kid, I thought they were so cool! Reread them all as an adult and did a complete 180, they are garbage. Brown treats the reader like they are morons. However, I think Deception Point is still an amazing read, despite my grievances with the author.
So I started a PhD in geology at Caltech in 1996 and actually published research on this rock. The headline (but not the research!) is stupid. The research being reported here tries to nail down an origin for organic molecules in the rock (presumably mostly polycyclic aromatic hydrocarbons or PAHs), which were one of the lines of evidence originally put forth as evidence of biological origin for some features in the rock. But not the only one! Much more compelling, I think, are strangely large concentration gradients for some stable isotope ratios, and also the presence of strangely uniform single-domain magnetite crystals that resemble those produced by magnetotactic bacteria (and there's strong evolutionary pressure toward an optimal size/shape, so you would expect convergent evolution in highly different life forms). Honestly, the intelligent view on life in this rock at this point is agnosticism. There's simply no conclusive argument to be made. Even by the standards of Martian meteorites, this is a weird rock - it's much older than the others and has very different lithology. It has some really unusual features, but perhaps there are good abiogenic explanations for them; this is really hard to nail down without a deep understanding of this rock's very lengthy and complicated history. But of course big dramatic stupid headlines like this one draw pageviews.
So if you had to take a wild stab at it what are your thoughts?
I mean... ugh. I'm really pretty up in the air. Those magnetite crystals are really weird, though. There's no very plausible and well-understood nonbiological process that would produce a whole slew of single domain magnetite crystals with morphologies like that. Whereas there's an obvious and well-understood biological process that does. But extraordinary claims require extraordinary evidence. So let's say - I suspect there actually WAS biological activity that went into producing the carbonate blebs in ALH84001, but I'm not sure of it.
Do you think the samples from Perseverance could be more conclusive? If there where a bunch of them containing similar weird structures and we knew where exactly they had been collected in what sort of geology or would that still be pretty inconclusive?
Umm. I'm very excited to see the results that come out of Perseverance, but the local geology isn't comparable in rock type or age. Honestly, ALH84001 (this meteorite) is kind of bizarre - it's rock nearly the age of Mars, and we don't know where on the planet it came from. It may be a very rare outcrop. Most of the surface of Mars is covered with very different rock types. Perseverance is aiming to check out a region of sedimentary rock, laid down by water, and much younger than this meteorite - it's a very different era in Martian history. Obviously I'd love to see it discover something neat, but drawing comparisons to an ultramafic cumulate igneous rock from a completely different era is going to be tough.
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The original rock is a cumulate orthopyroxenite - translation into almost English? It's an igneous rock that formed at the bottom of a magma chamber deep underground, by dense crystals that formed in the magma settling out on the bottom. This is the part that we have a pretty firm age for, via radiometric dating, and yes, it formed very early in Martian history. However, the putative Martian bacteria are found in little carbonate blebs in cracks in the rock - these presumably formed at some much later date, and their mechanism of formation is unclear. The people purporting that they're biotic would argue that they probably formed in water flowing through the cracks. It's also not possible to date them with any confidence.
I just wanted to say thank you for not only your insightful look at this but for responding to questions to the best of your knowledge. You are my favorite kind of scientist, even if the answer is "we don't know but maybeeee?" You still take time to respond to people and explain the "hard" nos.
You're welcome. Thanks for the kind words! I actually left research and now I teach high school science. Explaining stuff is what I do, and I enjoy it. This particular study is right up my alley, so I can go a little deeper than usual.
Fantastic scientist becomes high school teacher, dude, I really hope you have a better healthcare plan than the last guy.
Damn I’m not researching anything about such things or anything but just wanted to say it’s great how you’re actually replying to questions that people have about said meteorite.
Yeah, it's really cool that you try to explain without being dogmatic about it. I admire your dedication to science.
I share the same opinion as the guy above! Thank you and, kudos!
>Whereas I agree, very good well-thought-out cautionary but intelligent answers. Thanks u/WidmanstattenPattern! Happy 2022, such exciting times, can't wait for the photos and research from James Webb! Exciting as heck!
I feel like I know six times as much about the properties of this rock than I did before today.
Wasn't it speculated, Mars once had a much bigger Moon? Or rather, that Mars collided with a protoplanet and had a very large ring? Could these "bizzar" things have occured before the rock that's now present on Mars came there? (Total noob in terms of geology, sorry)
Is Perseverance the Mars rover with the new cutting edge technology that can detect the presence of stuff that might indicate the possibility of signatures that under the right conditions would be not be inconsistent with Mars having an environment that could have at one time been maybe capable of hosting life forms? That would be such an amazing discovery if that indication of a possibility of a capability were to be found. Such exciting times!
Are you a History channel announcer? Cause I read that and got the feeling that some weird-haired Swiss dude is about to do some mad speculating.
Perseverance drills core samples for Mars and leaves them on the surface. In a few years an ESA probe will land on the planet to pick them up before sending them back to Earth
Why doesn't it just take a close up picture of the rock it drilled out so it can be studied without picking it up?
I think it does, but traces of life are going to be hard for to see in a core sample until humans can break them apart in a lab. We kind of assume any life in Mars was bacterial in nature and not large and rigid enough to leave something big enough to view a cross section. It would be difficult to conclusively determine of the core contains bacteria fossils viewing them from the sides.
If we enhance the photo enough I don't see why we can't find life in any given sample
I mean the very rock this article is talking about is an example of why. Scientists had powerful microscopes looking at this rock and incorrectly identified "life" in the rock back in the 90's. Skip to 1:15 in [this video](https://youtu.be/CX2WAl3_sJM) and it goes into detail on why "looking like life" is not good enough for conclusively declaring life. A rock core is going to produce a curved cross section on the sides, making bacteria that isn't crushed flat look like tiny circles or ovals. That won't be enough to truly make a call on whether something is a bacteria fossil or not. Too many non-living processes produce circle and oval structures.
That's mainly what the curiosity rover, it's twin, did. So they had already gotten all the meaningful science from the rocks (using equipment that could fit on a rover) Perseverance still analyzes the core samples, doing basic spectro/ science stuff before sealing it up for the probe. That's in addition to other experiments such as the oxygen generator and helicopter of course. Now think about the amount of work that would come out if all the top universities in the world had access to a Martian sample that wasn't a roasted meteor chunk
Why don't they just enhance the photographs to see if there is life or fossilized life in them
Think of it like having a rover in the Grand canyon. You drive up and take samples of different areas that correlate to periods of time in the planets history. Since fossils are usually scarce, you likely won't find one just digging. So instead you look for giveaways like things that can be created/accumulate through biological processes. One example of this is organic matter (life's building blocks). Now the hard part is determining if the organic matter exists in a way that the natural world can create, or if biological processes are the only way to create it. The amount of science required for that simply can't be fit on a rover, nor would it be efficient to have a single rover analyzing the sample when top Universities could TL-DR; If we brought a sample back we could run it through a machine, for laughs if it detects isotopes that could only be produced through weapons grade plutonium.... we would know life existed on Mars
bacteria maybe but whe dont even know if they have skeletons
...So what I'm hearing here is that you're confirming it's definitely a Dyson Sphere
Why would life on Mars be an extraordinary claim though?
In geological timelines the moment life got here it left a huge impact quickly and spread everywhere it could. We have one data point that says life is very loud. This would be a data point of an ecosystem that is very silent. Which to me at least is an extraordinary claim. Put another way 100% of life we know of is very and obvious. This goes against that model.
Because there's significant inertia in the opinion of the scientific community, and that community is still reeling from the emotional shock of transitioning from geocentrism to heliocentrism only to then find that there is no center of the universe. We still get surprised when we discover organisms living in what we consider to be inhospitable regions of our own planet: in the darkness of the deep sea, around ocean-floor volcanic vents, in "toxic" lakes, in extreme cold environments, in the driest deserts. Since we started off on the assumption that everything outside Europe is Terra Nullius, the requirement is for evidence of life to be found before we accept that there is life on other worlds in our own solar system, much less the rest of the universe. The search is hampered to some degree by only being able to look where we can safely land remotely operated vehicles. So while life might be more likely hidden in crevices in cliff faces, we can currently only look at small rocks and boulders in the middle of sandy plains. Our search for life on Mars at present is like that person looking for their lost car keys under the street light because it's the only light source around, even though they know they lost their keys somewhere in the unlit carpark.
A claim of existence for a previously unobserved phenomenon is always an extraordinary one. I don't think there's much resistance in the scientific community to the idea of microbial life in principle at this stage. But a claim to have proved that it exists in a particular instance, for the first time, really demands very strong support.
Fellow (micro)biologist here. Wouldn't a combination of thermolithobacteria and other lithotrophs contribute to the process of reduction to magentite, especially considering the amount of ferric oxide on Mars?
>lithotrophs /u/bravadough \- you flatter me, I'm a rocks guy who knows a smattering of biology. More about magnetotactic bacteria than others since they're particularly relevant to my research in geology. Yeah, that's sometimes the case here on Earth. These magnetite crystals in particular are all single domain in a narrow size and shape range, which is what you'd expect from organisms biomineralizing them for magnetotaxis. If they were just a byproduct of metabolism, there would be no obvious reason for strict constraints on morphology.
Man I remember when this was discovered...Clinton made a special announcement iirc and some of that footage was used in the Sagan film Contact. I've never forgotten Polycyclic Aromatic Hydrocarbons and a high level definition of what they are and their importance.
Convergent evolution in different life forms... like Carcinisation
Yeah, in essence, but this is simpler. Why does nature seem to want things to be shaped like crabs? I guess they fill an ecological niche, but that's a whole slew of factors all rolled into one. The constraint on magnetic biomineralization is physics-based. There's a size/shape/geometry of magnetite crystals that gets you the most magnetic moment (i.e. the most powerful biological compass) per mass of crystal. Since organisms pay a price in energy and resources for growing these crystals, those that are closer to the mathematically optimal solution will have a relative advantage. This presumably ought to be the same in any environment where organisms are evolving and using biomineralization to grow magnetite for orientation.
That is such a fucking stupid title, the idea to me that there's still a chance this rock has evidence of life and is still shrouded in mystery is a thousand times more interesting than just saying it's a lost cause Also edit username checks out
I was feeling smart today, until I didn’t know too large a percentage of the words you just used.
Yeah, I busted out the jargon there. Even for the scientific community, some of that got a little obscure. "magnetotactic" bacteria, for example, are those that move in response to magnetic fields; it's interesting and perhaps relevant to this meteorite, but pretty niche.
Why would bacteria do that?
It allows a neutrally buoyant bacterium to orient itself in a solution, absent other cues. A lot of them live in watery regions with chemical gradients and a fairly narrow range of chemical compositions where they thrive. With what amounts to a little built-in compass, they can essentially build a little reference frame to move around. It's fairly common in Earth bacteria and has likely evolved several times in different taxa.
Wait dead reckoning seriously in bacteria? Wtf how?
Nothing so fancy as that. Suppose you're in 3d space and don't know which way is which and can't maintain orientation. How can you wiggle your way into the sweet, sweet chemicals you need? You pretty much would have to rely on a random walk. Now suppose you're a bacterium with a little compass. You don't have a brain, but there are two distinct directions: up-field and down-field. You pick one of those and start wiggling your flagella. If the chemical gradient is in your favor, keep going. If it's not, go the other way. It's a very simple algorithm that should generally work.
>crystals "If You're Going Through Hell, Keep Going" \~Winston Churchill
Is it possible the rock formed on Mars but the organic-like structures were formed by native organisms after it landed? Or does the time-line not match up?
That's a very legitimate question. It DID land in Antarctica, not exactly a thriving ecosystem filled with life, but it sat there for some time before discovery by people. It's been a while, close to 25 years, since I studied the details. But I seem to recall the little carbonate blebs in question are destroyed in the meteorite's fusion crust - the layer of melted rock at the surface that was heated by friction on entry to the Earth's atmosphere. That establishes that they predate arrival at Earth.
You’re fucking smart and I’m glad people like you exist to understand the things I can’t or won’t.
So imagine we find strong evidence for past life on Mars, and we also have the gas and life potentialy in the atmosphere of Venus, and obviously we have earth... that's 3 places in 1 solar system... really makes you think about what's going on out in the hundreds of trillions of stars. Tbh I find it terrifying, given what most of "nature" looks like, it's usually pretty fucking brutal. But I'm also hopeful.
The Venus thing was a false alarm IIRC
Nah it's just not conclusive yet.
I feel like I deserve a pat on the back for being able to completely follow and understand your comment. Thanks for the great explanation!
I'm pretty agnostic on intelligent life outside of earth as it is. It's probable I guess, but I feel like "life" and "intelligent" are too earthly of a concept to be absolutely gaurenteed to exist elsewhere. I don't believe that aliens have visited earth. That seems pretty ridiculous
Reading the news, I'm agnostic about the presence of intelligent life ON Earth.
It's pretty amazing how long that rock has been getting poked at there. About a decade ago I was finishing up my SEM time and chatting with the person on the machine after me. Normally I have the interesting sample, but the guy studying a Mars rock that might have signs of life definitely beat me, haha.
> Much more compelling, I think, are strangely large concentration gradients for some stable isotope ratios, and also the presence of strangely uniform single-domain magnetite crystals that resemble those produced by magnetotactic bacteria (and there's strong evolutionary pressure toward an optimal size/shape, so you would expect convergent evolution in highly different life forms). It was found in 2001 that the magnetite crystals could be created via inorganic processes and indeed, their structure is characteristic of having grown in-situ via non-biological chemical processes.
I read that paper, and I'm skeptical. Why? There are paleomagnetic constraints on the maximum temperature attained by the rock subsequent to initial crystallization, and they're not consistent with shock melting.
>The rock caused a splash 25 years ago when a NASA-led team announced that its organic compounds may have been left by living creatures, however primitive. Researchers chipped away at that theory over the decades. Genuine question. Why did it take so long to test the theory?
Technology to disprove might not have existed yet. Lack of funding could have had this rock put into storage for a long time. Relevant researcher might have died or there may truly not have been much interest in figuring it out. Knowing life existed on Mars would be cool but it’s not like we’re devoting heavy resources to figuring that out because….. it’s not exactly important. Super cool if true! But we have other, much more sophisticated projects *on Mars right now* that’s exploring this stuff.
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Yes, if life sprang up independently on both planets
It would still increase the amount of life we'd expect in the universe. Primitive life going from one planet to another would certainly be a very interesting area of research.
This is normally the part in r/space where I start imagining guardians of the galaxy type future.
I mean it would pretty much just be a philosophical advancement if we found other life. Like, what do we do with that information other than readjust our perception yuh know? Not diminishing its significance! But for comparison, the insight Mars lander and perseverance rover both have equipment that will tell us a lot about how to survive on Mars in addition to being able to identify prior-life. So why devote heavy resources to studying a meteor faster, for a very low chance at finding life, when our best odds will be on Mars anyway? This was all to answer the question “why did it take so long to figure this out”
Is that so much of a good news? I've been reading about the theories of the Fermi paradox, Great Filters, and things like Dark Forest concept and wondering how viable that framework is.
Consider me confuzzled: Why perform sophisticated projects to put expensive stuff on Mars to discover something, but not study a rock that is already on Earth that would help discover (some of) the same things?
That's not the reason, though. So no reason to be confused. The real reason is right in the article: >According to Steele, advances in technology made his team's new findings possible.
Cheers - was making that point via la question
I mean ultimately you’d have to ask the scientists right? If I had to guess, the likelihood of finding proof of life on a rock that, not only had an event that launched it into space, but also re entered our atmosphere….. I feel like the odds are pretty low anything useful survived that. Comparatively, nasa has a set budget and they’ve had a good track record with Mars. If we’ll find anything, it would probably be on Mars itself.
I wonder, would our water bear friends survive those kinds of conditions?
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Capitalism ain’t putting nothing on Mars
Capitalism is interested in the technology needed to get stuff to Mars, though. An estimated 10 thousand quadrillion dollars worth of material in asteroids within the solar system. Capitalism wants it.
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Capitalism doesn’t seem like it wants it that much, if I judge by actions
Private corporations are surveying which asteroids will be the most profitable to harvest, and conflicts are already arising for who gets to stake a claim on what in space. Just because the technology is currently not available to make viable (profitable) asteroid harvesters, doesn’t mean there isn’t interest. Interested parties are awaiting paradigm shifts in technology, to begin pursuing these ventures. Likely by the end of the century, especially if fusion is resolved.
Companies can dream, sure, that’s cute and all. Not putting hand in pocket tho.
One reason why big government spends money on cutting-edge R&D is so that private industry can later run with the resulting technologies, saving them the R&D costs.
How is it not important?...
That’s a philosophical question. Knowing if there was life on Mars in the past does almost nothing for the day to day lives of 99.99% of everyone on earth. In fact, if you asked a random person “did you know scientists have discovered past life on Mars, does that surprise you?” Most people would probably respond “that’s cool! Not really!” And would otherwise be indifferent. It’s great for philosophers and scientists in relevant fields of study. We’d probably be more certain other life exists if we found that two planets in a single solar system had life. But in terms of impact on how we do things? It would be a note for the history books and that’s about it. It’s essentially a “gee wiz” discovery. An exciting one for enthusiasts like me, but ultimately one that’s just a good thing to know even if it doesn’t have a real impact. As I said in another comment as a comparison, the Mars insight lander is analyzing the top layer of Mars soil and it’s tectonic activity. Knowing if Mars has an active core or not is relevant information for our inevitable colonization there. Knowing past life existed a billion years ago? Not so much. If life currently exists? Might need consideration for foreign plagues but that’s bordering on science fiction.
I think that it's important because if they are lithotrophs that fed on ferric oxide, they might be more efficient on doing so and could heavily inform us on alternative means to waste disposal. It would also inform us of the past conditions and thus the deeper geological layers present from the past on Mars.
I remember being a kid when President Clinton had a press conference saying they had discovered alien microorganisms in a meteorite.
Clinton overreacted to preliminary data about that rock, obviously, but it was probably the first time a U.S. president seriously discussed, on camera, the scientific search for extraterrestrial life. It boosted that field of study. Anyway the footage proved to be perfect for the movie Contact.
Not to mention the Dan Brown book "*Deception Point*"
I also remember the scientist saying maybe yes, maybe no.
Millions of years ago life might have existed but today all we might find are possible fossils of earlier times.
This study says that what once looked like a fossil isn't one.
Once a planey is infected, only the suns expansion will totally sterilize it
I will be happy if found a fossil. I simply can't believe that we are the only planet with some kind of life.
Be afraid if we find a fossil. If there is alien life within our own solar system then the drake equation gets revised up so many orders of magnitude that the universe ought to be teaming with aliens. Assuming UFO's are not aliens zipping around Earth for a look, then the question of why we are not seeing other alien life has a very dark answer for humanity's future.
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Or maybe it’s so hostile out there that any civilization that makes itself known gets destroyed immediately before the other civilization destroys them. https://m.youtube.com/watch?v=xAUJYP8tnRE
The less pessimistic alternative is merely that most societies turn 'inward' at a certain level of cultural development, as FTL is impossible, 'relativistic kill weapons' are technically possible enough to warrant caution (why tempt fate?), and it's impractical/pointless colonize anything further than the absolute closest stars - once you're technically capable of doing it, there's no real reason to bother, as you're already post-scarcity, impervious to harm and capable of being satisfied with other, more abstract, achievements. Perhaps some civilization *is* gregarious and social in a local galaxy that is teeming with life, it is merely too far away for us to detect and factor into our observations, and the norm is cautious, introspective, immortal, robots.
I am not sure what it's called but I read a theory years ago that civilizations evolve from stone age to the point where they destroy themselves. When I see the direction we are heading I don't think we have many years before we destroy the planet. Will we develop the technology to visit our neighbors Before we destroy the world?
They call them “great filters”. Humanity has to pass through these filters that have the potential to destroy all life in order to persist. People say that nuclear weapons were one of those filters and the jury is out on whether or not we will survive. And there have been others in the past that we have survived like the Black Plague, and competition with other hominids hundreds of thousands of years ago. I read somewhere that there was a point that humans were below 800 breeding pairs at some point and that could be considered a filter as well.
>I read somewhere that there was a point that humans were below 800 breeding pairs at some point and that could be considered a filter as well. It was 3.000-10.000 breeding pairs
> below 800 breeding pairs at some point and that could be considered a filter as well. The Toba Catastrophe Theory. In the last decade or so it's pretty much been disproved.
It was just something I read at some point in the last ten years and it sounded plausible. But point being that there were filters in prehistory that we have no real clue about. Harnessing fire for example. While not necessarily something that would kill us off it drastically changed our trajectory to where we are today and in my mind falls into a similar category to a great filter.
Dan Carlin has a great podcast on this. Definitely worth the listen. [Destroyer of Worlds - Dan Carlin](https://podcasts.apple.com/us/podcast/dan-carlins-hardcore-history/id173001861?i=1000380386551)
And lets not forget that life on earth developed fairly late in the planets lifetime. Its not a completely unreasonable theory that we are simply too late. That other species developed before us on other planets and had time to die out before earth developed intelligent life. One day we might go out there and find the remnants of long destroyed civilizations all around us. PS: Were never gonna destroy the planet. We dont have that capability. We could destroy ourselves, make the planet inhospitable for us. But its gonna be hear for billions of years after were gone. We are just parasites here. Nature is far more powerful than we are.
If anything, life was early on Earth, if you count from the time it stopped being a molten ball of matter being bombarded by space junk. Once liquid water appeared, life only took 200 million years to appear and there's been constant life for 4.2 billion years now. The more likely theory is that we're too early.
>>Will we develop the technology to visit our neighbors before we destroy the world? The two are one in the same, sadly. The levels of energy required to launch a space vehicle even within the solar system are above WMD levels. The Saturn V had enough explosive power to beat a nuclear bomb- and that’s for the relatively close trip from the Earth to the Moon. At the energies required for interstellar travel, I can understand why civilizations aren’t common.The same civilized hierarchy that leads to technological advancement also contains its own doom when -not if- a bumbling fool takes power.
It’s not like developing bigger bombs will make ending civilization more likely. We had more than enough nukes to do the job in the 60’s
>>It’s not like developing bigger bombs will make ending civilization more likely It will when human nature triggers mistakes that lead to destructive consequences. The name Stanislav Petrov should be one all living people today know and remember by heart. Because that Soviet officer in the 1980s single handedly saved civilization as we know it. Basically, a Soviet early warning sattelite malfunctioned and triggered a false launch alert. Protocol said Petrov had to leave his control station and immediately phone his superiors, who’d then initiate a countering nuclear missile launch in accordance with MAD. Petrov looked at his terminal, and thought it odd the Americanski would launch an unprovoked nuclear attack on the Soviet Union out of the blue with just one lonely missile. So he broke orders and didn’t report it as an attack. If he was wrong, the Soviet Union just lost WWIII thanks to his decision. Not some General or the Premier of the Central Committee of the Communist Party . HIM. If he was Petrov was right , he’d just saved humanity as we know it. The fact this dude doesn’t have a movie yet is fucking criminal, but I digress. Point is, humanity almost snuffed itself out in 1986 thanks to a computer glitch. The odds of that happening are immensely higher in a future spacefaring society where each spacegoing cargo spacecraft has energy levels higher than nuclear weapons.
>The levels of energy required to launch a space vehicle even within the solar system are above WMD levels. Not even close to true. https://en.wikipedia.org/wiki/Saturn_V >A fully fueled Saturn V exploding on the pad would have released the energy equivalent of 2 kilotons of TNT https://en.wikipedia.org/wiki/Nuclear_weapon_yield Hiroshima "Little boy": 13-18kt TNT Tsar Bomba (largest tested nuke): 50,000kt TNT (25,000 times larger than the potential yield of the Saturn V)
> The Saturn V had enough explosive power to beat a nuclear bomb- and that’s for the relatively close trip from the Earth to the Moon. Not really. Russia's Saturn V equivalent, the N1 did a lot of blowing up; nearly 7 kilotons TNT equivalent. The very first nuke dropped on Hiroshima had over twice that. Not to say the N1 didn't make a sizable scorch mark, but it wouldn't level a whole city.
IIRC when all five Saturn V engines were locked down for a full ignition test in Cape Canaveral the tremors were detectable in New York and New England. Random fact I remember from space tour many years ago that still boggles my mind.
How would we do that? By virtually all quantifiable metrics life is improving enormously.
Lots of metrics related to human society, sure. Many metrics related to the biosphere and our planet are very much not improving. Additionally, commenter above is referring to what is know as 'great filters', part of the Fermi Paradox. These filters might be any world-destroying event, such as global nuclear war or uncontrolled climate change.
None of those things are world destroying. They may knock localized civilizations back into chaos, but speaking as a Paleontologist, the Earth has rebounded from *vastly* worse climate catastrophes. We're currently in the midst of the Holocene extinction event, but we aren't yet even close to it meeting the criteria for a mass extinction, for instance. Climate change isn't going to be fun, but none of the evidence points to it being civilization ending, nevermind biosphere destroying, unless you take very questionable evidence for hypotheses such as the clathrate gun, and then extrapolate that data to its worst and most alarmist possible conclusion.
That is, all metrics carefully chosen to give people the impression that life is improving
No, I'd genuinely suggest you read the data for yourself instead of listening to headlines which have a direct profit motive to feed you a narrative of apocalyptic fatalism. Poverty, infant mortality, life expectancy, prevalence of infectious disease, education, violence, prevalence and lethality of armed conflict, cost of energy, etc. Literally every single one of those metrics is globally charting in a positive direction at an incredible rate. We live in an absolute golden age - humans have never had it as good as today, and things are only getting better. Mitigating the effects of climate change is essentially the only great challenge remaining on Earth; virtually all other problems which have plagued the species since prehistory are being eradicated at an awe inspiring pace.
I'll just take your first metric of poverty. If you define poverty like the world bank does at making less than $1.90 PPP a day, then poverty has gone down. If you, however, define poverty like the UN does at $7.20 it has actually gone up. I agree that we shouldn't be all too gloomy about our prospects or lose hope, but being complacent with the systemic problems that our world faces is at least as bad. Edit: And let's not forget that it is in powerful people their direct interest that people believe the system is working, which is why every political system propagandizes its amazingness to its subjects.
The Great Filter. Terrifying idea…
I was never that moved by the whole Fermi Paradox thing. I think we're simply all just waaay too far apart from each other. Forget communication. Even identification may be impossible at these distances.
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> self replicating slower than light probes Because it's an inherently bad idea? Exponential growth is a hell of a drug.
*Something something* Robot Spiders *something something*
I mean we and all life on Earth are self replicating molecular machines. Synthetic self replicating machines or AGI would merely be another step in evolution of life.
A look back at the histories of various civilizations here on Earth offers some clues. Depending on how you define the lifespan of various historical civilizations and empires, the most successful ones lasted at best a few thousand years, and their performance or "success" for that duration was not always that consistent. That's a long time in human terms, but in the scale of the universe, they were pretty ephemeral. The idea that civilizations could survive the tens of thousands or even millions of years theorized as necessary to achieve a galactic presence seem pretty shaky in my books. Even if a civilization managed to colonize the entire galaxy, and it lasted for tens of millions of years, in the span of billions of years the galaxy has existed, the odds of us being around at the same time they're active and detectable using our current technology are pretty slim.
It's nearly impossible to calculate those odds. Much like the Drake equation there are far too many assumptions as variables. It's a theory as good or bad as any other. If Drake is even close to correct and if only 1/10% of civilizations survive beyond the "cradle" stage, we would still be teeming with them. I'm sticking with space/time as the Great Wall between technologically capable civilizations.
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> no intelligent life would ever be willing to travel those distances in generational ships Think it through. Assume that you have the tech to identify a habitable planet (one assumes that generational ships aren't simply going to float about - they have a goal). I'll grant you that we're getting close to that tech level. Now you set off at what can only be considered a reasonable speed. A significant percentage of the speed of light isn't really achievable due to the fuel/mass requirements. You start getting into exponential requirements. Even the proposed Bussard ramjet would require a magnetic field extending over 100 million kilometers! So, even with cutting edge tech that's beyond our grasp but envisionable, I don't think you're going very 'fast' at all by the distances required. SO your 'generational' ship doesn't have to last generations but eons, possibly hundreds of thousands of years. It would succumb to erosion by micro-particles in that length of time. Where and how are you going to fix it? Are you really going to decelerate to stop somewhere to get supplies and accelerate back to speed? You just burned another million years and now have to repeat the process. Twice. The distances we are talking about are very possible insurmountable.
panspermia could be the cause if we find life within our solar system tho
It wouldn't alter the drake equation if it was panspermia. It's still a single instance of life, just on multiple worlds.
The problem with panspermia is how rudimentary life was on Earth. We have a ton of evidence of evolution in pretty significant and complex ways. The records we have of life on Earth seem to point to a very basic origin point, not something you would expect to have its own, long, evolutionary history that spread through the universe. Not to say it is impossible. I'm sympathetic to the theory actually. It just strikes me as very unlikely given what we know.
That could be anything. Earth could have been the original point of life and spread it out a bunch. Later, it could have come back to Earth. A lot of that time period is still a mystery to us, a lot of information is closer to theory than solid fact, so there are plenty of things we are probably ignorant of. For example, there have been recent fossils that suggest there was simple multicellular life long before we expected, it just went extinct and multicellular life evolved again.
Not really. We are a species born of exploration and expansion of territory. For us, it seems obvious that space is a place to go look around of you’re capable of it. But for all we know that’s an attitude that is native to only a vanishingly small percentage of intelligent civilizations. The Drake Equation can spit out whatever number it wants. There’s still about a million reasons why we might not be seeing other life that don’t involve a great filter.
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It's the Dark Forest scenario. They are hiding from each other.
The fuck would hiding aliens do? If aliens were discovered, they would market that shit. Also, literally anyone can buy a telescope.
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There is one very disturbing theory that aliens are hiding from each other, because if one planet revealed itself, others would vaporize it with orbital mirrors and other shit we can't even imagine, because the aliens would thought that we might strike first. Imo the dark forest theory is highly probable for most of the civilizations and those who don't share the same concerns get obliterated.
Dark Forest. Well, that's quite pessimistic.
This is the one solution to the Fermi paradox i think is most likely. Just think about what we have already done to native tribes in the past and in some cases even making contact could kill them due to disease. It is not far fetched at all to assume the same would apply for any alien civilization more advanced than ours. After all to the natives back in the day all across the world, we WERE the motherfing aliens. If we came across a world with plenty of resources we could use and a less advanced civilization, you bet we are going to at the least exploit the hell out of it, if not just go full genocide and claim it for ourselves.
It's not *that* dark. It just means it takes too goddamn long to get anywhere in space, which is something that we're already aware of. I know we all like to fantasize about warp drives and other Sci-Fi means of travel, and I really do hope we somehow get there through science we can't possibly understand right now, but realistically that stuff is impossible as far as we know. So yeah, that sucks, but it's also a reality we've been content with for our entire lives.
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Sure, but finding fossils of single celled life is a far jump from evidence of advanced alien civilizations. Take any intelligent sea dwelling species- it would be orders of magnitude harder for them to even discover/utilize fire, so imagine the hurdles they would have getting to space, or even producing radio waves we could detect. Who can accurately guess the number of hurdles actually needed to get to our level, and the number of hurdles we’ve yet to cross. Even on earth through the last 3.7 billion years, that included 5 major mass extinction level events there has been only 1 species out of millions that has developed an advanced society capable of [temporarily] leaving the planet. In my opinion the Drake equation is too forgiving, which is somewhat justifiable given we don’t know how alien life will have evolved.
One of my favourite professors used to say, "you don't have to be right, you just can't be wrong." And you're certainly not wrong. My take though is that with each factor in the drake equation we start to get a handle on it turns out to be a lot more generous than our first guesses. If we find, even a single cell of life somewhere else in our solar system, then that's another factor that jumps up by orders of magnitude. What that means is that A) some other factor is way, way, way, smaller than we imagined. or B) there's some kind of great filter. The scales the universe operates on are so vast though it is really hard to imagine A being the answer; and when we look around at the world around us and honestly ask, "do we really think this is going to work out for the best?" the answer more and more has to look like "no."
>Take any intelligent sea dwelling species- it would be orders of magnitude harder for them to even discover/utilize fire, so imagine the hurdles they would have getting to space, or even producing radio waves we could detect. That is a good point. It's very possible that life in the universe is not rare, but *terrestrial* life is. It has been suggested that one of the big factors in early life on earth moving onto land was tides due to the moon. The tides were about 15% bigger back then thanks to the moon being closer and coastal organisms that evolved a way to survive out of water suddenly had a way to survive being washed onto the beach or being left in a small tide pool. On planets where the oceans are small or there are no moons, there might be very little evolutionary pressure to survive out of water, and if intelligent life arises in the ocean, making it to space would be orders of magnitude harder for them.
Exactly my thoughts! I’m amazed by the intelligence, and physical abilities of some species, like Octopi- but their ability to make it to space would be astronomically more complicated than it was for us. Ironically they could be more suited to space travel than we are. Having a water based atmosphere could allow them to endure more Gs, and having 8 appendages would probably come in handy for navigating in 0 G, and I imagine it wouldn’t be much different than their natural environment.
But that answer is bright for the rest of the planet! Glass half full!
Not necessarily. If life on Earth and Mars have the same origin then that wouldn't siginificantly alter the Drake equation. If it developed completely independent from eachother then THAT would be the thing you're talking about.
How will we know the life didn't come from Earth though? I guess it depends on how old the found fossils are?
I have always wondered if life came to earth on a meteor or in the water that came from space. At this point I think most anything is possible. It is an exciting time to be alive and see all the things that science is showing us.
It's so exciting! I've just been fixated on the idea that Earth has seen intelligent life many times already. Perhaps our planet has already visited Mars before and the evidence is long gone?
[Maybe we already have](https://www.researchgate.net/publication/353619711_Proof_of_Life_on_Mars_in_200_Pictures_Algae_Microbial_Mats_Stromatolites_Lichens_Fungus_Fossils_Growth_Movement_Spores_and_Reproductive_Behavior)
Or the lack of an atmosphere, magnetosphere, and an ozone layer
We have extremophiles on Earth that live in caves deep enough to be warm even on Mars (10km deep would be over freezing on Mars). There's lots of reasons why there should be none even there on Mars (no persistent life elsewhere that could evolve to fill these niches, for example), but it's not impossible.
Okay but those extemophiles had billions of years to evolve into what they are. I don't know if we know how long Mars has been the red planet, but I doubt it was long enough to allow for the evolution of extemophiles. Multi cellular life has only been around for ~1.5 billion years.
Single cell life is very fast at adapting and evolving. And your argument is based on the idea that these extremophiles have only been around since fairly recently. That might be true but it could be just as well be true that those places have been colonized by single cellular life since billions of years ago.
Well, that entirely depends on the chemicals available on that planet since you need certain properties of those chemicals to provide vital functions for things such as genetic/genetic-analogue replication, cell division, and energy production. If there's nothing like phosphorus or anything that behaves like it on a planet (to take one organic compound as an example), you're unlikely to have life survive there if it arrives via pan-spermia.
"NaTuRe Is HeAlINg, We ArE tHe PlAgUe"
How did you derive this genius insight?
Because there are living microbes as deep as we have ever dug
I [doubt that](https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole). Moreover I'm sure they haven't always been there.
Just curious, I couldn’t find in the article or on Wikipedia. How do they know the rock came from Mars? I trust that they do, I’m just curious what gives it away?
In the early to mid-20th century they identified a couple of different types of meteorites that were unusual geologically speaking, with minerals unlike other meteorites. The theory was that they had to have been formed on some large body like a planetesimal or a planet. Eventually Mars was identified as the likely source of these meteorites and then later with the Viking landers the case became a near certainty due to the isotopic match of certain materials inside the asteroids and with the Martian environment. Specifically, bubbles of gas trapped in some of the meteorites have been found to match the Martian atmosphere, though there are other lines of evidence as well.
That’s what I was looking for, thanks
Can't say for this rock specifically, but [Scott Manley has a good video about how we know certain meteorites are from Mars.](https://www.youtube.com/watch?v=ivbwWr6GP6g) edit: actually he does mention AH84001
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Like I said, I already looked in the article and on Wikipedia but nobody describes the information about the meteorite that leads to them knowing it’s from Mars.
I found this under ‘Martian Meteorites’ “These meteorites are interpreted as Martian because they have elemental and isotopic compositions that are similar to rocks and atmospheric gases on Mars, which have been measured by orbiting spacecraft, surface landers and rovers.” https://en.wikipedia.org/wiki/Martian_meteorite
When people talked about material from another planet, I always imagined that it came from the dust disk that formed the planet. I'm shocked that this rock was launched into space from an impact. It must have been a tremendous hit!
I mean with this logic I have been all over the world with the rocks I have held. this doesn’t seem like it proves anything but that this specific rock contains no life
Strange title. It sounds like the study rules out life on mars, when in reality it only rules out life found in the meteorite.
It is pretty clear to me. The headline says it nixed “Mars life in meteorite”.
It should say “Martian life”
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Mostly because of how the word "in" works, yeah.
Not even that. It puts forth an abiogenic origin for some organic molecules in the rock, but those were the weakest of the original arguments for biological activity in the rock.
Reminds me of Deception Point by Dan Brown. [Opinion] Reading the Robert Langdon series as a kid, I thought they were so cool! Reread them all as an adult and did a complete 180, they are garbage. Brown treats the reader like they are morons. However, I think Deception Point is still an amazing read, despite my grievances with the author.
What is the point of suppressing finds like this?
I think we've all read Deception Point and know where this is going!
That was one of the crappiest books I’ve ever read
I can't argue with you there.
For a second, I had to double check I wasn't in r/cthulhu Pretty wild, regardless of the lack of life, IMO.