I read this less as "this makes it more likely that there was life" and more as "if there was life, this makes it more likely that we'll have found it".
> Perseverance's soil and rock samples will be brought back to Earth by a future expedition and studied for evidence of past life.
Can someone explain to me why we need to bring the samples back to Earth to analyze them? What "signs of life" are we looking for that the rover itself couldn't report?
Without being an expert, I would say that samples on Earth would let us (or at least those who look at the samples) look in ways the rover was not designed to look. There is a lot of analytic equipment that is here on Earth but not on Mars.
Also, there are things to study besides past life. Geology, material science, horticultural implications, and other things are all worth study
The "past life on Mars" maybe interesting but it is also an easy selling point.
As little as 20 years ago, the idea that Mars had a lake, like honest to God lake, or that we'd gather 1000s of exoplanet signatures, or that we'd find solid evidence of a liquid ocean on Europa. All of this would be bananas.
It may not feel fast on the scale of a decade, but on the scale of my lifetime this is breakneck pace. Not fast enough now that I'm middle aged, but so fast.
Everything is amazing, even if you already knew it was amazing, just let it be amazing.
Funny to think about how different people perceive the rate of change. Growing up before they landed on the moon, seeing a smudgy black and white blob walk around in a funny way to getting robots onto MARS, with "realtime" (radio-time) imagery is insane, the stuff of HG Wells.
Growing up after the landing, with science fiction being a pervasive genre, color television, the internet, you can see how to some it might feel like a lot of hurry up and wait.
The perspective of "one day, we might just see that moon up close" to "well duh we are going to mars."
On the other hand, much of this had always been anticipated. E.g, Fermi's question from 1950 and the Drake equation are essentially based on the presumption of exoplanets. Or, the sensors (automatic mini labs) of the Viking probes in the 1970s were essentially based on the assumption that any life on Mars would be based on water (which in turn includes the presumption that there either are or had been significant amounts of water, an assumption strong enough to include this equipment, in the first place.) What has changed, since, is sensor technology.
It should gives impetus to further (and more targeted) effort - e.g., the killer evidence would be some kinda fossil, but what mechanisms of fossilisation would we expect to have existed on Mars? Perhaps stromatolites? We're still working out how to identify abiogenic stromatolites from biogenic ones.
And where should we look? It's kinda hard to build a robot that can replicate a sunburned human wandering around hitting rocks with a pickaxe and looking thoughtful, and likewise, a probe that can take a core sample of a former lakebed is a very specialised probe, if it's even possible to build one that could drill deep enough to where any postulated evidence of life might be found.
Only a sentence or two of the article talks about life. The article is actually about the ancient lake bed and how they confirmed it and the technology used to find it.
I think the Viking approach from 50 years ago was the right one: Send miniature labs to Mars and look for signatures. The Rovers are funky as all hell and the Skycrane is a masterpiece of engineering. Once down, they don't go very far or very fast and they look for biology-adjacent stuff instead of biology itself.
I think this can be seen as a change to acknowledge the need for context in order to make a robust (and hopefully correct) argument for possible evidence of life (fossil, trace, or otherwise). In all likelihood you're not going to find this uncontestable smoking gun and so you're going to need your robot geologist to collect much more than one sample in one place in order to rule out alternative interpretations. The Viking approach doesn't get you that.
If martians had built anything cool there we would have known by now. It's just not very likely there's much interesting up there unless you're interested in the little things.
It's a lot of people here - HN does occasionally love a space story, but typically Mars stories are met with insults, sarcasm and vitriol for those who are interested in it.
Edit: The effect is so strong, I have occasionally wondered if it is a concerted effort to get more people to start Mars startups, like nerd sniping. "Hurr you can't go to Mars like ever!!" -> "....just watch me". lol.
The parent didn't dismiss just this story. They seem to have pre-emptively dismissed the actual discovery of life on Mars if it were to ever happen, because it would be just the little things anyway…
If there is any life - even just "little" single-cell microbial type life - that is a huge huge huge change for human society.
We'd have actual proof that we are not the only life in the universe (even if just on Mars it may be microbial-like). Actual proof that we are not special or unique.
I view it as like when a small baby/toddler realises that other people exist and that they are not the sole focus of the world's attention - a major development milestone.
That barely scratches the surface of how much society and life on earth will change.
Religion, life's meaning, our place in the universe -- everyone will face an immediate reckoning here and have to reconcile their previous notions.
But even more impactful is that we'll start to be able to make much better approximations of Fermi's Paradox. It might suggest that the universe is teeming with life. Then questions about how it evolves and reaches sentience will move to the forefront. We'll have much better ideas.
We might start to get a little anxious about what's lurking out there, and we will probably start spending massively on space telescopes.
A lot of people believe that life isn't unique to earth in the universe and I personally wouldn't face a reckoning by this being confirmed.. I would however face a reckoning if it were somehow proven that earth was unique.
Silurian hypothesis is specific to Earth’s geologic record which we’ve sampled all over the world millions of times. It’s less ridiculous to posit the same happening on Mars where we’ve only sent awkward robotic explorers. We haven’t explored any of the lava tubes or done ground penetrating radar studies or cut thousands of core samples all over the planet so we really have no idea what’s buried there like we do on Earth.
Ancient Martians - was the giant face visible from orbit we made with cleverly aimed meteorite impacts not enough for you? Oh sure, it's just a rock you say. Well duh, we had to make it with _something_.
I agree with the part of being sick of it, but I also wonder why it even matters.
So what if there are microbes in the maritian soil? What difference does it make to us? Except possibly the worst invasive species incident in human history.
At least this isn't into the total wing-nut fanatasyland of living on mars, which is one of the stupedest ideas proposed in modern time.
Just bury a trucking container in Nevada and live in it, That's exactly what living on mars will be like, except the line of logistics will be much more practical.
If there are microbes on Mars, then studying them could tell us a lot about life on Earth. So far, we're trying to extrapolate from a single example.
The most interesting result would be to discover that Mars life is unrelated to Earth life. In that case, the universe is probably overflowing with variety of life in every suitable niche.
Or perhaps we'll keep searching for a thousand years and never find a trace beyond Earth. In that case life may be exceptionally rare.
> Or perhaps we'll keep searching for a thousand years and never find a trace beyond Earth.
If we find evidence of current/past life on Mars, what is the math that this means there's "overflowing" life throughout the universe?
And of course, the inverse: If there is no evidence on Mars, what does this show whether there is no current/former life outside the inner solar system (besides Earth)?
Maybe we spend less on Mars (at least for now)? So much more out there than ancient lakes?
> If we find evidence of current/past life on Mars, what is the math that this means there's "overflowing" life throughout the universe?
If life on Mars is related to life on Earth, that doesn't tell us very much.
If it's not related to life on Earth, then that means life can arise easily, so we should expect to find a lot more examples. Currently any instance of life is guaranteed to find at least 1 example (itself), so moving from 1 to 2 is significant.
> If there is no evidence on Mars, what does this show whether there is no current/former life outside the inner solar system
Evidence for the "Earth is special" hypothesis gets stronger the harder we look and find nothing, but we can never know for sure. At this point, we've hardly looked anywhere.
Anything proven or disproven adds to our collective understanding. You could apply that new information to old or existing problems and possibly come up with new or useful results.
Think “what would the proven existence of microbes tell us about a theory like the Fermi paradox”?
If it's demonstrated that life is able to develop independently on other planets, it seems reasonable to me to infer that any planet/moon with water and geothermal vents would have complex lifeforms. Possibly even intelligent.
If life on Mars had a separate origin (say, with a different genetic code) it would be strong evidence that life is common in the universe.
However, they'd need to rule out transfer of life between Mars and the early Earth. If they can't do that, this is still somewhat interesting, since it could mean life was transferred back and forth between Mars and Earth during that period. It might also mean there's still life deep in Mars' crust where liquid water can still exist, and that life could give more information on what early life was like (being another branch of our evolutionary tree).
But there's still potential for a pretty significant quality of life decrease. And... we're petty, so it's not too crazy to imagine that if you anger several billion of us by making it worse, then it might not be safe for you here.
I don't think we're quite so coordinated as that at present, but who knows what the future holds.
I only see this opinion on HN really. HN as a community is obviously large and split, but the virtriol here against people that are interested in Mars science, habitability, etc is so intense. People here have told me to go live in my mom's basement and shut up about my interest in Mars. Or to go bury myself in Nevada. Or go live in Antarctica. And it's always said with such disdain, effectively insulting and hate-filled comments towards those who are interested or curious about something.
I'll never let the HN Mars-hate-fest ruin my curiousity - but boy is it annoying to read sarcastic comments about how dumb people are for being interested in something.
Go ahead though I guess. We all know you are well aware that living on a different planet is quite different from living under Nevada. Your hyberbole is ridiculous and it's like, do you want us to really think that humanity as a whole would agree that living on Mars is "exactly" the same as like, living in a basement in Nevada?? Uh-huh.
If we discovered for-sure even one single tiny microbe anywhere off Earth, that would only change a fundamental fact of the entire rest of the universe forever like when we discovered that the rest of the universe exists at all and that the Earth is not the center of Gods sno-globe. It would only mean there absolutely is other life out there even if we never meet them because of the sheer scale of everything. No big.
It's just the basic nature of reality changing. You can't eat it or fuck it, and your Netflix subscription will still be annoying, so what does it matter amirite?
There are so many areas of science that you could argue don’t make any difference to us. Should we stop research into black holes? How about astronomy all together? Why even spend money on NASA and any of its space exploration programs? Are all the people involved in these areas wasting their lives away? I mean all they’re doing is adding to the corpus of human knowledge. /s
There are a variety of terraforming proposals with not totally insane price tags. To some, creating a livable biosphere in 1/3rd earth gravity brings exciting space travel prospects.
That's what terraforming is - it creates/modifies/brings what is needed for an atmosphere and water and everything else.
We can't keep our current planet habitable because of current forcings that are not present on Mars, like varying governments, greed, incentives, etc. Plus, trying to live sustainably on Mars is likely to teach us more about how to live sustainably here.
It's quite a logical fallacy to suggest we shouldn't/can't try to make Mars human habitably simply because we're struggling with Earth right now. Doing both things at the same time would be related to each other and help each other.
The most likely candidate for the atmosphere is melted co2. Mara would have liquid oceans if the co2 ice caps were melted away. From there, a biosphere would need to be introduced for oxygen production. The main limiter on earth based animal life would be a lack of buffer gas such as nitrogen, and the excessive co2 concentrations.
