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Earth was born dry until a cosmic collision made it a blue planet
- alexey-salmin 1y agoAh the First Impact
- rd07 1y agoI know this reference lol
- zkmon 1y agoAll life on Earth is illegal immigrants from another planet.
- ReptileMan 1y agoOnly if the earth was seeded with life.
- pfdietz 1y agoWhich is possible, at least from sites elsewhere in the young solar system. Life might have originated on Mars, for example, or perhaps in one of many small, warm, wet asteroids. These early asteroids were kept from freezing up by the presence of short lived radioisotopes, the decay products of which are detectable today in parts of meteorites.
- subscribed 1y agoWhich seems to be quite possible. This is what we have from just one mission: https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Rosetta_s_comet_contains_ingredients_for_life https://www.esa.int/Science_Exploration/Space_Science/Rosett...
- zkmon 1y agoSorry, I was only joking. Someone got busy seriously down voting! Maybe wrong times to utter the phrase "illegal immigrants". I get it.
- prerok 1y agoWell, I for the count of one, didn't think it bad, but thought provoking. We're all immigrants, when you get deep into it (speaking from Europe, where we usurped previously native folk some 1500 years ago), and we all came from Africa anyway. But, yeah, political implications nowadays are a slippery slope.
- shireboy 1y agoThis could mean in the Drake equation ne -number of planets capable of life- is very small. A planet has to be hit with a comet big enough to deliver a large amount of water but not so big or fast to destroy it. And be in the Goldilocks zone of the star. Also the mass of the planet would play a part - gravity of more massive ones would be more likely to capture a comet. But again, too massive and I could see that hampering life.
- OgsyedIE 1y agoUnless collisions like the article suggests are a statistical inevitability, that is.
- dotancohen 1y agoHydrogen is the most common element in the universe. So long as you have elemental oxygen, it will react with things and hydrogen is the thing it will react with the most. So having water is almost a given for any Star system. Additionally, protoplanet and cometary collisions are in fact statistically inevitable. The real question is if water can be delivered at a point after enough gravity has amassed to ensure the water stays there.
- jug 1y agoRight, that's the sticky point? The likelihood of a planet in the Goldilocks zone to be too hot in the early stage of stabilizing its chemistry that it requires seeding with "post-formation" chemistry? Is that likelihood close to 100%, or maybe not even near and we were just set up for a funny cosmic event.
- xbmcuser 1y agoYour assumption we need water for life to exist is in my opinion wrong. We only know Earth so assume that is what is needed for life to exist.
- yosefk 1y agoWhat's the chemistry of life without water? Do you refer to the promising Russian studies of life sustained by alcohol?
- akk0 1y agoHow does this square with the fact that we have solid evidence of water on Mars as well?
- lukan 1y agoHaving some water and having lots of water is a slight difference. The most arid dessert on earth is a jungle compared to Mars. (Also Mars could have been also hit.)
- oceanplexian 1y agoExcept Titan likely has more water on it than Earth. Therefore unless we’re a fluke of a solar system planetary bodies with water on them should be extremely common.
- deleted 1y ago[deleted]
- addaon 1y agoTitan is outside the frost line. There’s no question that there’s a huge amount of water in solar systems, the question is if there’s a consistent transport system (comets, in this case) that moves it inside the frost line to where liquid water can, given an atmosphere and gravity, exist in conditions that match our familiar conditions for life.
- lukan 1y agoTitan is interesting, but much further away from the sun, so different conditions. We want earthlike conditions, life that can sustain on anything else, is just hypothesis so far. (As is the claim from the article)
- munchler 1y agoThe article mentions that the inner planets were initially too hot to retain water, but presumably Titan didn’t have that problem, being much farther from the sun.
- 1y ago
- stared 1y agoImagine this sci-fi plot twist: Aliens make live habitable by hitting proto-Earth with a planet, so life can sprout there. They calibrated it such a way that angular size of Moon is the same as of Sun.
- WillAdams 1y agoThat is pretty much the premise of Hal Clement's short story "Halo", which I read in _Space Lash_ (originally published as _Small Changes_), but now available in: https://www.goodreads.com/book/show/939760.Music_of_Many_Spheres https://www.goodreads.com/book/show/939760.Music_of_Many_Sph... I recommend folks read it in reverse chronological order, starting at the back, then working to the front and bailing when things get too quaint/old-school/golden-age.
- aitchnyu 1y agoWhat if they miscalculated and intelligence evolved when the moon drifted too far to cover the sun?
- layer8 1y agoThey regularly smashed asteroids onto earth until intelligent life emerged.
- rstillwell 1y agoSmashing will continue until morale improves…
- shagie 1y agoI would say "spoilers" ... but it's the title of the story. The Fermi Paradox Is Our Business Model https://en.wikipedia.org/wiki/The_Fermi_Paradox_Is_Our_Business_Model https://en.wikipedia.org/wiki/The_Fermi_Paradox_Is_Our_Busin... https://www.tor.com/2010/08/11/the-fermi-paradox-is-our-business-model/ https://www.tor.com/2010/08/11/the-fermi-paradox-is-our-busi...
- vardump 1y ago
- pfdietz 1y agoOriginal paper: https://www.science.org/doi/10.1126/sciadv.adw1280 https://www.science.org/doi/10.1126/sciadv.adw1280
- greenchair 1y ago[flagged]
- quesera 1y ago> but please trust the science! If you're going to disparage the best idea humanity has ever had, you are required to commit and explicitly suggest your preferred alternative. Your attempt at clever irony is a negative contribution to the world.
- wizzwizz4 1y agoIt is precisely the tendency of scientists to qualify their certainty that makes them worthy of our trust.
- munchler 1y agoReading comprehension: The collision with Theia likely had a large effect on Earth once it occurred, but the collision might still have been unlikely to occur in the first place.
- praptak 1y agoSo we're not only made of elements which formed inside star(s) but also ones merged from two different planets. This is weird.
- aeonik 1y agoAnd the remnants of two neutron stars colliding.
- alchemism 1y agoAs above, so below. Two humans colliding, too.
- neuronic 1y agoIn the scale of the universe this is bound to happen, likely infinite times anyway and this is what feels rather weird to me. Not just the perceived "special circumstances" but that independent of the rarity it will still happen many many times and then any conscious lifeform developing technology to realize this be subject to the definition of survivorship bias.
- ahazred8ta 1y agoThere was a giant incandescent donut involved, too. https://en.wikipedia.org/wiki/Synestia https://en.wikipedia.org/wiki/Synestia
- timbowhite 1y agoIs this the same collision theorized to have created the moon?
- wvbdmp 1y agoYes
- rcostin2k2 1y agoThat's what is suggested here but according to the Giant Impact Hypothesis the impact happened about 4.5 billion years ago and formed the Moon from debris, and it likely vaporized much of any existing water on proto-Earth rather than delivering it... More investigations needed ...
- blindriver 1y agoAbsolute garbage. The Earth has a nearly perfect circular orbit. Any collision with another planet would have pushed it off its orbit and caused it to at the very least created a more elliptical orbit that likely would have made the swings in temperature more deadly for life on Earth. This entire article is science fiction.
- indigodaddy 1y agoThis makes some sense actually. Does anyone have a counterargument to this?
- o11c 1y agoIt's backwards. Highly eccentric orbits are the default; near-circular orbits are the inevitable result of averaging out a large number of orbits after they collide. It's also ignoring the fact that we likely did have additional planets, but after interactions with other planets with nearby orbits, they would have been either ejected out of the solar system entirely, caused to collide, or herded into more circular (non-overlapping) orbits. This is why Pluto is not a planet.
- deleted 1y ago[deleted]
- prerok 1y agoWhile I agree with you on most points, that is not why Pluto is not a planet. The reason is that it was observed "too soon" because of its interaction with Neptune's orbit. Once we realized there were plenty of such objects in the range of Neptune's orbit but we also realized that these were not fully formed planets, we invented the term of dwarf planet, so Pluto was demoted to that status, which it shares with many other objects in the far out orbit. So, it was just a classification thing. We could have also said all those others are also planets.
- the_af 1y agoIsn't the most common scientific theory about the origin of the Moon that a big body collided with Earth? How can it be science fiction if most scientists currently believe this?
- sethammons 1y agoRelated, a recent study suggests up to 1% of our mantle is water trapped within rock that gets released as subduction increases to higher heat and pressure. This water could account for three times the amount of water on the surface and may represent a whole-Earth water cycle. https://www.bnl.gov/newsroom/news.php?a=111648 https://www.bnl.gov/newsroom/news.php?a=111648 I wonder how this ties in with the submitted link about Theia. And it will be interesting if we ever get similar trapped water discovered in martian rock.
- ck45 1y agoThis reminds me of Stephen Baxter's novel "Flood"
- danudey 1y agoThere are structures in Earth's mantle which are believed to be leftover chunks of Theia, which makes the connection feel quite plausible. https://www.newscientist.com/article/2400567-bits-of-an-ancient-planet-called-theia-may-be-buried-in-earths-mantle/ https://www.newscientist.com/article/2400567-bits-of-an-anci...
- mcswell 1y agoThe article says the light elements hydrogen, carbon and sulfur (and oxygen?) were only able to condense on the outer planets (and their moons). And the original article specifically says "the inner Solar System planets Venus and Mercury are largely devoid of volatile elements". If that's the case, why does Venus have so much carbon dioxide? (I'm not saying the article is wrong, just trying to understand.)
- o11c 1y agoKeep in mind that carbon dioxide is almost 3x heavier than methane. Part of the reason Venus has "so much" CO₂ is because all the lighter gasses have been depleted. (But yes, Venus is hard to satisfactorily explain, regardless of whether you accept the article's conclusions at face value.)
- pfdietz 1y ago> why does Venus have so much carbon dioxide? Venus doesn't have liquid water, which is needed for the reaction of silicates with CO2 ("weathering"). Without that reaction, CO2 just accumulates in the atmosphere. Most of the carbon on Earth (and there's a lot) is locked up in rocks. There's also a biological effect. Here on Earth, silica in the ocean is scrubbed out by microorganisms that create silica shells; these tiny shells fall out into sediments, where (in deep ocean) they eventually form a kind of biogenic rock called "chert". Elsewhere, typically in shallow water, carbonate rocks are formed from the remains of other kinds of animals. Without these effects, the dissolved silicon concentration in seawater would be orders of magnitude higher, and the silica would react to form clays. This reaction would acidify the ocean and prevent carbonate formation. Just such "reverse weathering" has been hypothesized to occur after the Permian-Triassic boundary, where CO2 levels stayed elevated for 5 million years. The extinction event was so severe it disrupted chert formation (a "chert gap").
- andrewflnr 1y agoI've tried reading the paper, which is obviously less hand wavy than this mess of a blog post but pretty tough going for a layman. I still don't see how they conclude that the water arrived all at once instead of in a bunch of comets... https://www.science.org/doi/10.1126/sciadv.adw1280 https://www.science.org/doi/10.1126/sciadv.adw1280
- hammock 1y agoAll at once is what explains the isotopic homogeneity (e.g. in oxygen) between the earth and the moon
- andrewflnr 1y agoMeaning not just all the water but all the oxygen came in with Theia?
- o11c 1y agoI also don't see how they disprove the contribution of gravity. Remember that Earth is composed of fifty Titan-sized bodies. Titan, and probably Uranus and Neptune, probably have their methane etc. as a result of outgassing - initially, the volatiles are embedded in the inner rocks, but as they gravitationally differentiate and heat - and are subject to tide-like interactions with other bodies - the volatiles are released. (The real questions are "Why does Ganymede not have an atmosphere?" and "What's up with Venus, really?")
- andrewflnr 1y agoI believe the idea is that the water was all cooked out of Earth's protoplanetary disk material before it even formed large chunks. So gravity never got a chance to "contribute" on that front.
- o11c 1y agoWell, that seems to make 2 major assumptions (and several minor ones), both of which are probably false: * that the planetesimals that formed Earth had the same orbital characteristics (notably eccentricity), rather than being averaged out. * that planetesimals formed from dust in largely the same manner as planets form from planetesimals
- animitronix 1y agoNot buying it, Mars had water with no major collision.
- GWBullshit 1y ago[flagged]
- TacticalCoder 1y ago[dead]
- spenrose 1y agoClaude Sonnet 4.5 summary of the original paper [https://www.science.org/doi/10.1126/sciadv.adw1280 https://www.science.org/doi/10.1126/sciadv.adw1280] for middle school students: How Earth Got Its Water: A Cosmic Detective Story The Big Question: How did Earth become a planet with oceans and life, when it formed so close to the hot Sun? What Scientists Did: - They used a "radioactive clock" made from two elements: manganese and chromium - Manganese-53 breaks down into chromium-53 over time (like ice melting at a steady rate) - By measuring these elements in meteorites and Earth rocks, they figured out WHEN Earth's basic chemistry was locked in Key Finding: Earth's chemical recipe was set within just 3 million years after the Solar System formed (that's super fast in space terms!) The Problem: At that point, early Earth was missing the ingredients for life—especially water, carbon, and other "volatile elements" (stuff that evaporates easily when hot) Why Earth Was Dry: Close to the Sun, it was too hot for water and other volatile stuff to stick to the rocks that built Earth—they stayed as gas and floated away The Solution: About 70 million years later, another planet called Theia (which formed farther from the Sun where it was cooler) crashed into Earth: This collision created our Moon It also delivered water and other life-essential ingredients to Earth The Big Takeaway: Earth needed a cosmic accident to become livable. Without that lucky collision bringing water from the outer Solar System, we wouldn't be here! Why This Matters: If Earth needed such specific, lucky events to support life, habitable planets like ours might be much rarer in the universe than we thought.
- deleted 1y ago[deleted]
- flufluflufluffy 1y agoWhat I don’t understand is how you define a single point (even if the point spans a million years) of “when the solar system formed.” They say the chemical composition of the Earth solidified “only 3 million years after the solar system formed” — isn’t the formation of the planets itself part of the formation of the solar system? How does one define the moment of formation? Or does this mean that we know with certainty that there was no physically consistent body one could identify as “Earth” 3 million years prior, and then within those 3 million years, it coalesced and solidified?
- thangalin 1y ago> How does one define the moment of formation? We don't. It's usually within a range. My illustrated book shows the timeline with more context and detail. Note that the events are provided on a timeline with some uncertainty (e.g., ± 1 million years): https://impacts.to/downloads/lowres/impacts.pdf https://impacts.to/downloads/lowres/impacts.pdf
- flufluflufluffy 1y agoThat’s what I was thinking but I guess the uncertainty is less than I assumed. Btw your book is AMAZING!
- frutiger 1y agoI was under the vague impression that there is a single moment when the gravitational force in the core of the proto solar system outweighs (ha!) the electromagnetic repulsion of deuterium/tritium nuclei and fusion is achieved. The resulting radiation pressure clears out the debris from the solar system’s accretion disk, and this process surely is not instantaneous but is relatively fast.
- buildsjets 1y agoI wonder how much adenine, guanine, thymine, and cytosine was present in that water.
- Panzerschrek 1y agoI don't understand why all these volatiles (hydrogen, nitrogen) didn't evaporate during such huge collision, which likely melt the whole Earth's crust. Even if a temporary atmosphere was formed, with high post-impact temperatures this atmosphere can't stay long.
- ricksunny 1y agoAs far as we know, molecules and atoms escaping into space comes due to the solar wind. Somehow the solar wind activates these atoms and carries them off into the distant vacuum, ad infinitum presumably though (I would imagine) limited by the heliopause. [edit, benefiting from convo: mechanisms on atmospheric escape, to varying degrees of verification) • https://en.wikipedia.org/wiki/Atmospheric_escape https://en.wikipedia.org/wiki/Atmospheric_escape • https://en.wikipedia.org/wiki/Hydrodynamic_escape https://en.wikipedia.org/wiki/Hydrodynamic_escape ] Absent that, our treasured atmospheric molecules would have to autonomousy achieve escape velocity, some 22 km/sec , with no outside assistance. A difficult feat. And so, resident atmosphere.
- Panzerschrek 1y agoWith high enough temperature some molecules may achieve velocities enough to escape. The question is - how hot was it really? The initial collision happened at least with escape velocity, so there was roughly enough energy for volatiles an non-volatiles to escape. But non-volatiles condensed presumably pretty quickly (but were still hot) in comparison to volatiles.
- ricksunny 1y agoYes I was being a bit too glib in relegating atmospheric escape mechanisms exclusively to action by the solar wind. Lot of proposed mechanisms, uncertain how many of them are verified and quantified to what magnitude. https://en.wikipedia.org/wiki/Atmospheric_escape https://en.wikipedia.org/wiki/Atmospheric_escape https://en.wikipedia.org/wiki/Hydrodynamic_escape https://en.wikipedia.org/wiki/Hydrodynamic_escape As a layperson I see our current epistemological state as long on models, and short on empirical verification (because we're talking about a difficult phenomenon to verify). I think I mostly wanted to offer counterpoint to the original comment that 'this atmosphere can't stay long' i.e. even under elevated temperatures. (I'll probably update my prev comment with those wikipedia links.)
- ricksunny 1y ago>was rich in volatile elements essential for life, such as hydrogen, carbon and sulphur. Today years old on learning that 'carbon' is a 'volatile element'. (I come to learn that astrogeology has a unique definition of volatile). • The summary's own source article points makes no reference to carbon being volatile. • The wikipedia article for 'volatiles' in the astrogeological sense makes no reference to carbon being volatile https://en.wikipedia.org/wiki/Volatile_(astrogeology) https://en.wikipedia.org/wiki/Volatile_(astrogeology) . Similarly, the wikipedia article for 'refractory', posed as the astrogeological opposite of volatile, does not place carbon at all in the spectrum of volatile to refractory. • Contra: at least two papers do refer to carbon being a volatile element. https://www.nature.com/articles/s41586-022-05276-x https://www.nature.com/articles/s41586-022-05276-x and https://arxiv.org/abs/2311.18262 https://arxiv.org/abs/2311.18262 [shrug]
- eep_social 1y agoI take this as “volatile” in the sense that it bonds easily with other molecules
- brianpan 1y agoAstrophysicsts would also call these "metals" (anything heavier than helium) so don't read too much into it. :D https://sentinelmission.org/astrophysics-glossary/metallicity-in-astronomy/ https://sentinelmission.org/astrophysics-glossary/metallicit...
- ricksunny 1y agoThank you, that does make me feel at the same time better as an individual and sadder about my expectations for the astrophysicists’ ability to draw anything resembling reasonable conclusions about the makeup of the celestial bodies.
- brianpan 1y agoThere are different kinds of scientists to do that.
- catigula 1y agoTough to gain any predictive information here due to the anthropic principle requiring a series of comical happenstance for observation to even occur.
- erickf1 1y agoFrom a purely mathematical, scientific, and logical standpoint, I must regard this article as entirely speculative. The scientific claims it presents are extraordinarily improbable, and sound reasoning compels their complete dismissal.
- QuantumGood 1y agoHistory repeatedly shows that the popular: "extraordinary claims demand extraordinary evidence" is often dependent on the frame of reference. What is thought to be likely is used to frame conventional wisdom as truth, making the new viewpoint "extraordinary, until, over and over again, the new viewpoint becomes conventional wisdom. So "extraordinarily improbable" is really just an overton window framing (what we accept/don't accept), rather than a statement based in logic. Though your overall framing reminds me so much of historical phrases that I wonder if you are being intentionally ironic.
- cyberax 1y agoI thought the consensus was that the water came from comet impacts?
- ctingom 1y agoI don’t believe this.
- 3oil3 1y agoWe humans are not from Earth, what more signs need those who can't see? Humans,from all the species, the unique without a natural habitat. Humans, can not live on this planet unless we all get together and start adapting the environment. Otherwise, we can only survive and it's not fun. We have to wear clothing, cut downn trees. We get ill and stuff. Monkey us from? We closer to the pigs and not just the hips.
- poly2it 1y agoWhat?
- pinkmuffinere 1y agoYou heard the man! Monkey us from?
- 3oil3 1y agoHey that bit was for the lols, although it is quite valid to say, just missing plural and a comma. Innacurate in some ways -mainstream theory is not about coming from apes, rather is about sharing a, yet undiscovered, common ancestor. I mentionned the pigs because of promising advancement in organ transplantation, notably kidneys that reached a milesone recently, and I mentionned the hips because human hips and ape hips have an evolution-breaking distinction. I could go on and on, but let's wait for more science, it wouldn't surprise me that what knowledge we discovered and took for granted back then, when 80% of the world population did not know how to read, might be developped today.
- pinkmuffinere 1y agoI really appreciate your open response! Your writing style is so fascinating, it reminds me of how my dad used to talk (he was Persian, not a native English speaker). What’s your background? How did you end up with these beliefs?
- 1y ago
- marcoalopez 1y agoInterestingly, Earth scientists have long understood that plate tectonics is highly unlikely to exist on a rocky planet without water (to put it simply, water is needed to deform the Earth's upper mantle), given all that this entails. If this hypothesis is true, plate tectonics as such should be post-collision.
- osigurdson 1y agoTLDR: Theia
- renshijian 1y ago[flagged]
- JackAcid 1y agoHow did water-rich Theia get its water?
- fijiaarone 1y agoScience makes itself look dumb compared to creationism.
- watersb 1y agoWhat are the chances of the Earth forming yet remaining dry? Exoplanet surveys that I've seen in popular press can see rocky, dry planets. I'm not sure if that's just a selection bias in our current technology or if Earth with ocean and atmosphere is relatively rare.
- tiku 1y agoThe water also helped with cooling the surface right? And I thought this was already a widely accepted theory, that the water came from a meteor or asteroid.
- jijji 1y agothe fact is that there are over 700 quintillion planets in the universe, habitable is over 40 billion... i think our current understanding of physics limits our ability to reach any of them.