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Asteroid crater 520km in diameter buried in southeast Australia, scientists say
- ourmandave 3y agoI think it may have triggered what’s called the Hirnantian glaciation stage, which lasted between 445.2 and 443.8 million years ago... This huge glaciation and mass extinction event eliminated about 85% of the planet’s species. It was more than double the scale of the Chicxulub impact that killed off the dinosaurs.
- someplaceguy 3y agoImagine an asteroid causing a glaciation event on Earth that lasts 1.4 million years. That's mindblowing.
- _joel 3y agoI think it goes to show just how short of a blink of the cosmic eye, that humanity has really existed for and the need to spread our bets by exploring the universe.
- dsign 3y ago[flagged]
- Cthulhu_ 3y agoOnly if you want the species to survive, if you're more nihilistic like me, it just doesn't seem to matter. Or if you're optimistic, WE don't matter because there's loads of other life and societies out there. It does make you wonder whether life as we know it was a preceding civilization that launched life into the wider universe for the continued existence of life. But on tectonic timescales, any traces that e.g. a carrying vessel would have left behind are long gone.
- _joel 3y agoProbably one of the best episodes of Trek imho - https://www.imdb.com/title/tt0708803/ https://www.imdb.com/title/tt0708803/
- gloria_mundi 3y agoAnother related Trek episode - the one I expected you to link: VOY's "Distant Origin" - https://wikipedia.org/wiki/Distant_Origin https://wikipedia.org/wiki/Distant_Origin
- VHRanger 3y agoThat's a question in geology and archaeology called the Silurian Hypothesis: Could we even detect a millions-of-years old civilization in the geological record? 1. https://arxiv.org/abs/1804.03748 https://arxiv.org/abs/1804.03748
- NoMoreNicksLeft 3y agoAn Earth-originating civilization would have left our species bereft of the natural resources to industrialize with. Coal was only made once. Maybe if abiotic theory of petroleum is true, you get that back over immense timescales, but you don't get a second shot at coal. Without coal, you can't even do metallurgy at scale. Is there some gotcha that I'm missing?
- px43 3y agoMaybe that is what happened, and we somehow managed to make due without energon deposits and vibranium.
- deleted 3y ago[deleted]
- Retric 3y agoCoal was only made once because the earth basically ran out of carbon to turn into coal. There’s 1,100,000 million tons of economically viable coal and we’re running into environmental issues by burning ~1/1,000th of it. Most projections suggest coal use is going to plummet over the next 50 years, both because we have better options and because we have little choice. There’s enough coal in the ground to make earths atmosphere actively lethal to humanity. At ~70,000 ppm people are rendered unconscious in minutes and there’s enough coal go well over 100,000 ppm. There’s no way for humanity to use up the worlds coal as fuel, perhaps we could ship it into space as carbon source but that seems unlikely.
- shakna 3y agoWe're certainly setting a record at destroying this planet.
- Loughla 3y agoWe're certainly setting a record at destroying ourselves. It's seems like a pedantic distinction, but it's important. Earth doesn't care if we're here or not. The universe doesn't care if we're here or not. We are the only ones who should care, and we seem not to. The planet will be fine, eventually, after we die out. Life will continue after we're long gone. But we'll be long gone, and it's like we've all decided that's okay.
- SamPatt 3y agoDestroying ourselves, as measured by population, which is the highest in the history of our species? Or measured by longevity, or leisure time, or other living standards, all of which are drastically higher than they were only a few generations ago?
- krisoft 3y agoThose are all true! And they are important to remember. It is also important to remember that if you are driving a car to a brick wall, almost every metric will be perfect right until you hit it.
- SamPatt 3y agoIt's also important to remember that history is full of people claiming we're about to run into a brick wall (Malthus, Erlich and company), yet things just keep getting better. Perhaps humans are better drivers than you think?
- samus 3y agoMalthus was essentially correct, but wrong about the when and how. Industrializing societies can play whack-a-mole with constraints that limit their population growth, successfully so far. What saved us was the surprising phenomenon that those societies tend to have quite low birthrates. Multiple possible reasons for that: * high cost of living and raising children,* * availability of birth control, * waning social pressure of getting many children, * no immediate economic benefits of raising children (in agrarian societies, they are essentially free labor on the farm, and a huge young population makes it easier to bootstrap an industrial economy). Of course, eventually there will be a problem when a huge percentage of the population is too old to work. We will be fine as long as we can sustain agriculture: * oil must be a-plenty to run farming equipment. It will be a long time before electricity has taken over * we need farmland with intact soil and water * we need fertilizer (phosphorus is running low soon, and oil is required as well) * we need pollinators for many crops. Hand-pollinating is expensive * We must not run out of pesticides to maintain yields And probably some more requirements. If any of them is not fulfilled, society collapses and things can get ugly quickly. These things partly contribute to recent wars in Africa, the Middle East, and other places. Edit: *: low child mortality makes it necessary to actually support most children all the way to adulthood
- short_sells_poo 3y agoI agree with you and I'm saddened by the nihilist (and defeatist!) outlook that many people seem to have here. I'm fundamentally a humanist. I want humanity to survive and thrive. I never understood the defeatism. It seems to arise from having the intellect to recognize that humans can (and do) have impact on their environment, and in the same breath resign on that impact being only negative and thus declaring that humans as a species should go extinct. But there's so much good in this world that people do, isn't that worth saving? We know our capabilities are only limited by our own imagination, so why not strive for a grander human civilization that can span at least the solar system, if not the galaxy? We can try, and we may still fail. Nothing is certain, except the way to ensure our demise by accepting that our fate is to go extinct and do nothing about it.
- lazide 3y agoEh, frankly it’s giving too much rational basis to emotional states IMO. People posting on web forums, especially engineers, like to poke holes in things and aren’t big into expansion and exploration at the moment. Probably a bit depressed from sitting in front of their computers all day too. Ask someone who just spent a month on the pacific coast trail, or who is about to go to Antarctica the question, and you’ll get a different set of answers.
- oceanplexian 3y agoI think it's more than the web but the way media is being curated. I'm one of those people who's really optimistic about society. However being a positive person is actually a lot of work. I basically have to tune out all modern movies, television, news. Every new TV show is about some dystopia or the end of the world or a Zombie apocalypse or whatever. I watch mostly old TV shows from the 50s and 60s and read science fiction. In rare cases I'll watch a new show that's actually positive. You have to be careful though, even long-running franchises can quickly turn toxic when Hollywood gets a hold of it; Star Trek was headed that way until Strange New Worlds came out.
- NoMoreNicksLeft 3y ago> I never understood the defeatism. It seems to arise from having the intellect to recognize that humans can It actually correlates really well with the advent of teaching young children to be guilty about the civilization which gave birth to them. Maybe we shouldn't be slamming first graders with the ideas that everyone who came before them were supervillains and that they must shoulder the burden of correcting long dead injustices. In any event, doesn't much matter. Every week there's a new article about how one nation or another has below-replacement fertility that doesn't seem to have any real prospect for reversing (tied to, more than anything else I think, what was described above). We are probably already a dying species, or at least heading into a post-civilization phase, and just don't know it yet.
- jklinger410 3y ago> and the need to spread our bets by exploring the universe. I would like for us to get our house in order before we start this process.
- prox 3y agoI feel this is a why-not-both thing. We should fix our house and explore. We have enough people and capability to do both if we are politically and mentally willing.
- bradgessler 3y agoYeah. If anything, not having our house in order is even more motivation to create offsite backups.
- d12345m 3y agoWhich problems do we need to solve before you would deem our species worthy of survival?
- mulmen 3y agoThis is such a tired and simplistic take. The space program has been helpful in tidying our home. It’s not an either or choice.
- JumpinJack_Cash 3y agoThat is a lie that is conveniently told to preserve the legacy of the Apollo program and the morale of the Nation, as well as the legacy of one of the most beloved figures in the history of the Nation: JFK , who by the way, when you start to dig deeper emerges to be just a younger Trump.
- mulmen 3y agoWe literally have satellites in space that monitor the atmosphere and detect greenhouse gas emissions.
- localplume 3y ago[dead]
- jacquesm 3y agoYou can expect one of the really big (Chicxulub-size) impact every 100 million years or so (there is enough uncertainty here that experts all have their own ideas on the exact frequency but typically 25 to 500 million years seems to be the agreed upon range. We keep finding new craters though and then have to increase the estimate). https://www.thespacereview.com/article/761/1 https://www.thespacereview.com/article/761/1 https://skyandtelescope.org/astronomy-news/how-often-do-chicxulub-level-asteroids-hit-earth/ https://skyandtelescope.org/astronomy-news/how-often-do-chic... And endless papers on the subject. TEOTWAKI is a fun rabbit hole to dive in to.
- someplaceguy 3y ago> You can expect one of the really big (Chicxulub-size) impact every 100 million years or so Still, the Chicxulub asteroid is estimated to have caused a global cooling of the surface by around a decade, not 1,400,000 years.
- jacquesm 3y agoSure, ask the dinosaurs how that went. The point is: that was only a decade and only a relatively small asteroid and the effect was that the dominant species of the time was wiped out. Size is inversely correlated with frequency, so those smaller ones happen far more frequent. Anything larger than that and it is definitely game over.
- barbariangrunge 3y agoWhat percent of species have humans killed so far? Are we going to eventually outcompete an asteroid causing over a million years of ice age? https://www.un.org/sustainabledevelopment/blog/2019/05/nature-decline-unprecedented-report/ https://www.un.org/sustainabledevelopment/blog/2019/05/natur... https://amp.theguardian.com/environment/2018/oct/30/humanity-wiped-out-animals-since-1970-major-report-finds https://amp.theguardian.com/environment/2018/oct/30/humanity...
- deleted 3y ago[deleted]
- w10-1 3y ago> it may have triggered what’s called the Hirnantian glaciation stage Maybe. but per the Brittanica article cited: > No concentration of iridium has been identified near the extinction that would suggest a bolide (meteorite or comet) impact like the one identified at the end of the Cretaceous Period.
- lordfrito 3y agoArticle says the center of the impact crater is (was?) around 30km deep. Curious how big they think the asteroid that caused this was. The article doesn't mention anything, and a lazy search online came up with nothing. Wondering just how big of an asteriod this was, and how capable we are of seeing candidate asteroids of this size.
- TacticalCoder 3y agoWell the article and the title here on HN both says "520km in diameter", which gives an idea (although there's more than the diameter to estimate the damaged caused by an asteroid, but 520km in diameter is quite something).
- ceejayoz 3y agoThat's the crater diameter, which'll be much larger than the impactor.
- hu3 3y agohttp://simulator.down2earth.eu/planet.html?lang=en http://simulator.down2earth.eu/planet.html?lang=en According to this calculator you get a 446km diameter crater if you input: - 15km asteroid diameter - 90º Angle - 80km/s - Dense Rock asteroid - Hitting on Water at level 10m
- aintgonnatakeit 3y agoFYI these are the maximums you can input to get the largest possible crater using this simulator.
- hu3 3y agoYeah I had to max inputs on that calculator. Pretty wild.
- irrational 3y agoWe’re going to need a bigger calculator.
- zhengiszen 3y agoMore important than the size, I think, is the angle of impact... Still huge numbers we could just fathom....
- throwbadubadu 3y agoDepends, but in general would say no.. energy is speed times mass, and mass is cubic in the size, while speed is linear. Angle is complicated, I mean unless it is very shallow all will still go into earth? I wonder if and at which angle it could impact earth's rotation, but for that then direction is also relevant (: *: Ah, interesting, the neal.fun/asteroid-launcher also gives same energy for different angles except very shallow ones.
- ridgeguy 3y agoEnergy is (1/2)(mass)(speed)^2. That ^2 term is important.
- Jyaif 3y ago> energy is speed times mass, and mass is cubic in the size, while speed is linear. https://en.wikipedia.org/wiki/Kinetic_energy#Kinetic_energy_of_rigid_bodies https://en.wikipedia.org/wiki/Kinetic_energy#Kinetic_energy_...
- CoastalCoder 3y agoThis sounds like the starting point for a cringey song about physics.
- alexpotato 3y agoI believe that all other factors kept the same, angle does matter b/c of the amount and time you spend going through the atmosphere. e.g. a shallower angle means you pass through more atmosphere which leads to more heating time which in turn means to "icier" asteroids burning off more of the ice. I can also imagine a scenario where the asteroid passes so close that it passes through the atmosphere but doesn't actually hit the earth.
- phkahler 3y agoI have always thought Lake Michigan/Huron look mighty round if you follow from the north end down through Green Bay and the Fox river to the west, and cut into Canada along the Niagara Escarpment [1] on the East. There seem to be signs of a round structure all the way down in Ohio. But while this does form a roundish structure, the history is quite different than an impact: [1] https://en.wikipedia.org/wiki/Niagara_Escarpment https://en.wikipedia.org/wiki/Niagara_Escarpment Still I wonder, what if this other stuff happened in this shape because of a giant impact crater billions of years ago before all that?
- sdflhasjd 3y agoThere's also the "Nastapoka arc"[0] of Hudson Bay that looks a bit cratery, but is apparently of a different origin. [0] https://en.m.wikipedia.org/wiki/Nastapoka_arc https://en.m.wikipedia.org/wiki/Nastapoka_arc
- progrus 3y agoSeems like maybe our ability to find and divert these asteroids might make all that burning of energy worth it, no?
- Capricorn2481 3y agoNot really, since there are only a few known instances of asteroids hitting earth in hundreds of millions of years, but climate change is an immediate threat within the next 50. The odds we live to see an asteroid hit us are slim.
- progrus 3y ago[flagged]
- Cthulhu_ 3y agoSlim, but not zero; we can and probably should do both.
- slibhb 3y ago> The odds we live to see an asteroid hit us are slim. Presumably this is based on a belief that humans are likely to go extinct. I don't agree; I think we're extremely unlikely to go extinct and, following from this, an impact is definitely something worth worrying about. It doesn't even have to be a "planet-killer," a smallish impactor could wipe out a city.
- suby 3y agoThe question is really how likely are we to be hit within the relevant time period. Had we taken a slower growth curve, we'd avoid climate change at the cost of an extra 50 or 100 years before being able to divert asteroids. That seems like a good bet. I am much more worried about climate change and irreversible destruction of ecosystems than getting hit with an asteroid in a very limited time period
- CoastalCoder 3y agoWell, maybe. It really comes down to the specific numbers. (At least for the objective part of the consideration.)
- botanical 3y agoWow that's a huge crater. It's bigger than the Vredefort impact structure in South Africa. The Vredefort dome is the second oldest at 2 billion years old that can be seen here: https://upload.wikimedia.org/wikipedia/commons/b/b5/Vredefort_Crater%2C_South_Africa%2C_OLI_satellite_image%2C_27_June_2018_cropped.png https://upload.wikimedia.org/wikipedia/commons/b/b5/Vredefor... And the full-sized version: https://upload.wikimedia.org/wikipedia/commons/5/52/Vredefort_Crater%2C_South_Africa%2C_OLI_satellite_image%2C_27_June_2018.jpg https://upload.wikimedia.org/wikipedia/commons/5/52/Vredefor... https://en.wikipedia.org/wiki/Vredefort_impact_structure https://en.wikipedia.org/wiki/Vredefort_impact_structure
- vidanay 3y ago> The impact structure was formed during the Paleoproterozoic Era, 2.023 billion (± 4 million) years ago. > The asteroid that hit Vredefort is estimated to have been one of the largest ever to strike Earth since the Hadean Eon some four billion years ago... Let that sink in (ugh) for a while. The Vredefort impact was so long ago, it's almost completely eroded away today. And yet, when it occurred the Hadean Eon was as ancient then as the Vredefort is to us today. The mind boggles.
- hinkley 3y agoThere's another one straight north in the second picture. That one looks like someone dropped a rock in mud on a hot day. I was confused about why the pictures seemed to have different craters, until I found the one you're talking about in the middle.
- moomoo11 3y agoThis kinda discovery is why I hold out hope there were super advanced ancient civilizations on earth. They just happened to figure out Stargates and peaced out entire cities to safer off-world locations.
- TearsInTheRain 3y agoDo you think a stargate is easier to figure out than redirecting an asteroid?
- mastax 3y agoLooking at that map, it's wild how many "confirmed impact structures more than 100km wide" there are just in Australia. There must be dozens of mass extinction events that we don't know about because the fossil record is so unclear past 500Mya. [0]: https://en.wikipedia.org/wiki/Extinction_event https://en.wikipedia.org/wiki/Extinction_event [1]: https://en.wikipedia.org/wiki/Chicxulub_crater https://en.wikipedia.org/wiki/Chicxulub_crater [2]: https://en.wikipedia.org/wiki/Earth#Natural_history https://en.wikipedia.org/wiki/Earth#Natural_history
- blahburn 3y agoGoogle "Chicxulub crater" for a fun animation
- jader201 3y agoFor the lazy: https://www.google.com/search?q=Chicxulub+crater https://www.google.com/search?q=Chicxulub+crater
- lostlogin 3y agoI wonder if more recent events will ever get this treatment?
- dotancohen 3y agoMaybe in another 60 million years, by whatever the cockroaches evolve into.
- deleted 3y ago[deleted]
- jandrese 3y agoAlso imagine how many hit the oceans. A water hit can be even more catastrophic than a land hit, especially on shallow water like the continental shelf.
- 3y ago
- coryfklein 3y agoI know it's buried deep, but it's kind of weird for the reporting to not even show an image of the area? Perhaps a map with a little pin indicating where the Deniliquin structure is? They say it's near the city of Deniliquin, which is here [0]. Oddly, that spot doesn't even show on the map of yellow dots of likely impact structures! Did they forget to mark their newly discovered largest-impact-crater-in-the-world on the map? [0] https://goo.gl/maps/shvRY2CiEs3eR8iw5 https://goo.gl/maps/shvRY2CiEs3eR8iw5
- foota 3y agoMaybe it's not yet considered likely?
- teddyh 3y ago> I know it's buried deep, but it's kind of weird for the reporting to not even show an image of the area? It’s something I have seen becoming the norm nowadays. Articles about art or photographs without a single image. Political articles about borders without a single map. Articles about some thing some scientist has done, maybe with a picture of the scientist, but not of the actual thing. And it’s not a technical limitation of the medium; most articles will have numerous (but irrelevant) images. I suspect that SEO measurement has told people that it doesn’t matter what images an article has, as long as it has some images, optimally interspersed with the text. Spending any money on getting relevant images thus becomes an unnecessary expense. Readers will still click on the article (because of the click-bait headline), and will still read (or at least scroll through) the article if the text is broken up by images by an optimal amount.
- fragmede 3y agoI think you're right. We know ChatGPT-4 can do image analysis, so all Google has to do is say that they're down ranking articles that don't have relevant images, and we'll be back to having useful images in artichokes again.
- fragmede 3y agotoo late to edit, but -2? if there's feedback for me on why, I'm all ears! (also, lol artichokes. ducking autocorrect.)
- bryanmgreen 3y agoLets say the same asteroid hit the same place in Australia today.... How many people would both directly from impact/shockwave and indirectly die (infrastructure collapse, tsunamis on beach towns, climate change, etc) from this, do we think?
- dmbche 3y agoNo sunlight for years, no photosynthesis - same pronostic of 95% loss of life id guess
- not2b 3y agoThis was bigger than the dinosaur-killer, which killed almost all land animals; only a tiny fraction survived. So almost everyone would die, all over the world. The shock wave would be extremely hot and kill pretty much anything that's outside, and the fires would be massive.
- mr_toad 3y agoThis is bigger than the KT impactor. Everyone would die. So would almost every other animal and plant on Earth. The lucky ones would die instantly, the unlucky ones in the following global firestorm. The really unlucky ones might live long enough to freeze to death.
- ChoHag 3y ago[dead]
- cubefox 3y agoGiven that land mass is smaller than oceans, there was probably an even bigger asteroid which fell into the ocean.
- echelon 3y agoWe might have found the biggest one, which could have led to the formation of the moon: https://www.express.co.uk/news/science/1606365/science-news-continent-sized-mystery-blobs-found-inside-earth-geology https://www.express.co.uk/news/science/1606365/science-news-... https://phys.org/news/2021-03-theory-large-blobs-material-earth.html https://phys.org/news/2021-03-theory-large-blobs-material-ea... https://www.science.org/content/article/remains-impact-created-moon-may-lie-deep-within-earth https://www.science.org/content/article/remains-impact-creat...
- autokad 3y agoyou can find large asteroid impacts by looking at Vulcanic traps and looking on the opposite side of the globe during that time.
- philip1209 3y agoIs there anything worth mining in these craters?
- ggm 3y agoSomebody really didn't want to go to the Deniliquin Ute Muster.
- Mimmy 3y agoShould we as a species be more concerned about a mass extinction event like this? The longer we survive, the more likely it'll happen. Isn't it just a matter of time?