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The world must cooperate to avoid colliding satellites and space debris
- dalbasal 5y agoIf I was writing a science fiction... space debris is a wonderful way of imprisoning a planet. Just put a bunch of junk in orbit, now no one can get out. Only a Han Solo type with asteroid avoiding skillz and a taste for danger. Maybe a built-in step in the intergalactic civilisation process is launching a bunch of satellites, letting them crash, and forming an orbiting wall. This gives baby civilisations a few millennia to grow into their newfound power as the space debris forms into rings, allowing launches again.
- MauranKilom 5y agoSpace junk, like everything else in orbit, moves at speeds measured in kilometers per second. There is no asteroid weaving that lets you dodge a pea-sized steel fragment approaching you at 16 kilometers per second.
- dalbasal 5y agoYou obviously have met my friend Han.
- thanatos519 5y agoBut I heard Han Solo made the Kessler Run in 12 picoparsecs!
- MauranKilom 5y ago> 12 picoparsecs That's... a length. About 230 miles or 370 kilometers to be exact. ;)
- saagarjha 5y agoAsk the Star Wars writers.
- jawilson2 5y agoThis is the plot of part of the Timothy Zahn Admiral Thrawn Books (Last Command). He cloaks something like 30 small asteroids and puts them in orbit around a rebel planet, but makes it appear like he might have released 100's. No one can enter or leave the planet until they are cleared, and they have no idea how many there are.
- uCantCauseUCant 5y agoThere is another book fallen dragon, were the descendants of a californian colony, "lock up the sky". Santa Chico is the name of the planet. https://en.wikipedia.org/wiki/Fallen_Dragon https://en.wikipedia.org/wiki/Fallen_Dragon
- PeterisP 5y agoObviously people can enter or leave the planet as long as they're willing to take a risk of dying equal to [space covered by 100s random orbits] / [total surface of planet], which is nonzero but small. If you're launching straight up, thousands of such asteroids would leave you with 99% chance of success - the trouble is that with modern standards we generally don't consider 99% good enough - e.g. for space shuttle, 2 out of 135 crashed, getting almost 99%, and that's considered not ok; but if you really need to (as opposed to launches just for PR and science) then you can definitely get out of planet 90%+ of the time.
- lttlrck 5y agoThere's a great sequence in Wall-E when he leaves Earth and breaks through the debris field. Not as you imagined but cool nonetheless. https://youtu.be/RmG5tUCrrsA&t=60 https://youtu.be/RmG5tUCrrsA&t=60
- deleted 5y ago[deleted]
- mike_hock 5y agoMaybe this is the solution to the Fermi paradox: Advanced civilizations tend to create runaway space debris collisions, preventing them from leaving their home planets.
- hosteur 5y agoThis is known as the Kessler syndrome. And it is not a good solution to the Fermi paradox by itself. Because it would only require a very small fraction of civilizations to avoid it to spread.
- deleted 5y ago[deleted]
- FeepingCreature 5y agoAlso, Kessler syndrome doesn't keep you from leaving the planet, just from having satellites. When passing through a debris shell, as opposed to staying in it for years, the collision risk is very small.
- labster 5y agoHow deep are those debris shells anyway? If we had a collision cascade in LEO, would geosynchronous orbits be generally safe? They’re pretty far apart, but I don’t know for sure.
- didgeoridoo 5y agoI have no intuition for this, as it is not modeled in KSP :) I’m trying to imagine a collision cascade that would generate debris with a significantly higher apoapsis than the original satellites… perhaps a head-on collision between prograde and retrograde orbits that ends up “squirting” some debris at extreme velocity in the normal/antinormal direction? Alternately, an object on a highly elliptical orbit (probably already space junk) near its periapsis with max kinetic energy hitting a satellite prograde?
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- mikemoka 5y agoan interesting take: https://www.colorado.edu/today/2020/05/26/solving-space-junk-problem https://www.colorado.edu/today/2020/05/26/solving-space-junk...
- cynusx 5y agoThat would work and incentivize effective removal of space debris too. It may even be implemented by consensus as it would generate revenue for the taxman.
- etothepii 5y agoSince space debris doesn't factor into the Insurance Underwriting pricing decisions at all of the space underwriters that I know it seems hard to believe this is a real problem.
- nabla9 5y agoAn actuarial modifier for underwriting OOS satellite insurance: Space debris mitigation, January 2021, The Journal of Space Operations & Communicator 18(01) >Insurers are already pulling out of the market for LEO due to the risks of collision and space debris. General market consensus indicates current premium volume about half of what it should be. https://www.researchgate.net/publication/348151316_An_actuarial_modifier_for_underwriting_OOS_satellite_insurance_Space_debris_mitigation https://www.researchgate.net/publication/348151316_An_actuar...
- perihelions 5y agoIt was reported this week that there was a catastrophic collision back in March, https://www.space.com/space-junk-collision-chinese-satellite-yunhai-1-02 https://www.space.com/space-junk-collision-chinese-satellite...
- rob74 5y agoWhen I read "avoid a catastrophic space collision", I thought about an asteroid hitting the earth and endangering life itself. Compared to that, a "catastrophic collision that knocks out one or more satellites key to their safety, economic well-being or both" sounds rather like an inconvenience. Of course, it could be "catastrophic" too, but there is catastrophe, and then there is catastrophe...
- zz865 5y agoAnd add to that "The world must cooperate..." you know it'll never happen.
- YinglingLight 5y agoThere is so much military hardware up there, military hardware disguised as civilian, satellites that were launched successfully but publicly described as a failure/"useless orbit". The article is essentially asking that all countries need to share the location of their nuclear subs because the Ocean is getting crowded.
- zabatuvajdka 5y agoTaking a step further, any nation could deliberately send a weaponized fleet to destroy satellites and then follow up with a ground strike.
- Qem 5y agoKessler syndrome itself could probably be weaponized as the cheapest superweapon ever. Say you rule over a small country, under risk of invasion by a much more powerful country, that relies heavily on GPS guided missiles, aircraft and ammunition. Probably it would not be very expensive to pick a couple fat satellites at the right orbital plane, blow them with small missiles able to reach orbital altitude, and let the resulting debris scattershot start a chain reaction to take down every GPS satellite in existence, rendering low to medium Earth orbit useless for centuries as a byproduct. Those smart ammunitions would be crippled overnight, forcing the more powerful country to risk old style boots-in-the-ground invasion, with much degraded technical support.
- protoman3000 5y agoOn a global perspective the interests of too many people don't align to reach any sensible consensus by conventional means. We see it with the pandemic, we see it with global warming and we saw it in general with every conflict and wars. How can we make this happen?
- Lex-2008 5y agoAre you describing what is also known as "Tragedy of the commons"? https://en.wikipedia.org/wiki/Tragedy_of_the_commons https://en.wikipedia.org/wiki/Tragedy_of_the_commons
- stackbutterflow 5y agoMore like the prisoner's dilemma, no?
- protoman3000 5y agoThe "Tragedy of the commons" is a situation where choices based on self-interest converge to a negative outcome. I would not characterize our situation on global level like that. The difference is that in our world people do express desire to cooperate, also on a global scale, but reaching consensus seems like an intractable or practically unsolvable problem. Everybody knows that cooperating lies in their own self interest, but what does it effectively mean to cooperate? It begins at different levels. For example, before we even begin to see disagreement on how to do the the things we want, we already have no consensus on what to do in the first place.
- PeterisP 5y agoArguably it is exactly like the tragedy of commons - the original analogy is common pastures getting overexploited as noone wants to limit their cows so that the pasture isn't overcrowded; and in this analogy noone wants to limit their satellites so that the space isn't overcrowded..
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- peanut_worm 5y agoI feel as though there are more clickbait headlines than usual on HN lately
- jnxx 5y agoFrom the article: > "Collisions are proportional to the square of the number of things in orbit," McDowell told Space.com. "That is to say, if you have 10 times as many satellites, you're going to get 100 times as many collisions. Unfortunately, any collision also increases the number of things in orbit, by breaking up spacecraft. The collision between Kosmos-2251 and Iridium 33 generated 1,300 pieces of debris in orbit. The collision between Object 48078 from Russia's Zenit-2 rocket and China's Yunhai 1-02 generated 37 known debris objects, and likely a lot more smaller untracked objects. This is likely to lead to Kessler Syndrome, a chain reaction of collisions once the density of debris fragments above a certain weight passes a critical density: http://aquarid.physics.uwo.ca/kessler/Critical%20Density%201991.pdf http://aquarid.physics.uwo.ca/kessler/Critical%20Density%201... Unless satellites are brought back to Earth, the likely path of development is that Earth will get a layer of satellite debris which makes a a good part of satellite technology basically infeasible (and any spaceflight much more dangerous).
- didericis 5y agoIf things got that bad I think there’d be increased incentive to invent something to clean it up. It’s a very hard problem, but it doesn’t seem impossible to deal with, I think it just requires fairly extreme intervention. I think most orbits naturally decay, too, so there’d be a time limit even if we couldn’t clean things up.
- i_haz_rabies 5y agoI wonder if there isn't already a team at SpaceX or something working on a few moonshot solutions.
- bell-cot 5y agoSpaceX probably has several rough-draft plans for mopping up dangerous orbiting debris sitting in a filing cabinet somewhere. BUT - So long as SpaceX avoids being seen as "at fault", any Kessler sh*t-storms that occur are likely to prove huge opportunities for SpaceX, and huge problems for all of their competitors. Most debris-storm clean-up ideas require plenty of launches, to get the Wonder Widgets and Space Squeegees into orbit. Likewise the replacements for all the smashed satellites. Which replacements may be substantially heavier, due to beefed-up propulsion systems for debris dodging, armor protection around their vitals, etc. And guess what company is the world's miles-ahead provider of low-cost orbital launch services, with an easy path to oh-so-profitable scaling up?
- hoseja 5y agoSpace is very, very big. The smaller the space is (lower orbits), the faster any debris decays and burns up. Whipple shields are a thing. I really don't see much potential for a catastrophe.
- nix23 5y agoThen this will be of interest for you: https://en.wikipedia.org/wiki/Kessler_syndrome https://en.wikipedia.org/wiki/Kessler_syndrome
- nix23 5y ago>hundreds of e-mail alerts arrive each day warning of potential space smash-ups Oh, so they could trow the Fax-machines out? Well done! Is Email not a bit unreliable for for such a topic?
- bolangi 5y agoPutting satellites in low orbits will help, since everything in those orbits will eventually decay.
- nikkinana 5y agoNo they don't, asshole.
- StreamBright 5y agoIt is kind of funny how humans cannot exist without putting garbage all around the places they visit.
- zarkov99 5y agoIn the US the first thing we need to figure out is whether the democrats or the republicans are to blame. Then we can decide if we are pro or against space collisions.
- pc86 5y agoThe only thing lazier than people trying to hamfist partisan politics into unrelated discussions is people complaining about it before it even happens.
- h2odragon 5y agoOrbits aren't stable. If they were, worrying about "kessler syndrome" and "we cant pollute space!" would make more sense. But they're not. Stuff put in orbit will fall (or possible escape), and its a real job to find an orbit where that doesn't happen quickly. Just like "COVID isn't smallpox".
- bayesianbot 5y agoSure, but when two objects collide and transform into 1000 objects, a lot more than two of them will find semi-stable orbits. And by semi-stable I mean it doesn't have to be stable as like with satellite, it just have to stay up there for years to be a problem.
- hunterb123 5y agoYou'd have to have a lot of energy to knock something from VLEO to GEO. I don't see it being a possibility, but I could be wrong, maybe someone smarter than me can do the math... Space is vast, if you have debris with a lifespan of 5 years, you won't accumulate enough for it to be unavoidable, and the issue will literally solve itself.
- lutorm 5y agoIt is _impossible_ to "knock" something from LEO to GEO. You can kick it to raise the apogee to GEO altitude, but the perigee will still be LEO. To change between two circular orbits, you need at least two impulses.
- deites 5y agoNice post!
- minikites 5y agoWe already can't work together to avoid catastrophic Earth problems like climate change, why would we start cooperating in space?
- stOneskull 5y agoplanes fly around without crashing into each other. the agencies involved work together there.
- ricardobeat 5y agoCould we have most things in space orbiting in the same direction? That would massively reduce the risk of collisions as their relative speeds would be lower, including any fragments resulting from a crash.
- Symmetry 5y agoThat's what we do for geosynchronous orbit, for example. But if you want a satellite to fly over the entire surface of the Earth to take pictures it'll have to be in a polar orbit and those all cross at the poles where the last major collision was.
- marcofiset 5y agoHow would you cover the whole planet if things can only go in a single direction? Things orbiting around a sphere must cross paths at some point in order to get global coverage.
- mLuby 5y agoIn general we do, because launching from west to east at the equator lets you use the Earth's rotation for a 465m/s speed boost. Launching the other direction means you need an extra 465m/s just to counteract the rotation you started out with. Polar orbits don't gain or lose much from the rotation since they're aimed over the planet's poles.
- diego_moita 5y ago> The world must cooperate The world can't cooperate to block spread of covid, to end hunger, to avoid global warming, to end traffic of sex slaves, to curb nuclear weapons, to end chemical weapons and land mines, ... Heck, even in some "civilized" countries people can't collaborate to achieve mass vaccination... Do you really have any hope we will collaborate on organizing space traffic?
- uCantCauseUCant 5y agoThe world can collaborate on not firing upon each other with nuclear weapons. Our "great" sociopathic leaders - worry greatly - at least for their own asses. Which means, collaboration is possible, its just not desired by all those deranged minds in power.
- krisoft 5y ago> Do you really have any hope we will collaborate on organizing space traffic? Yes. It's a much simpler problem with a lot fewer agents. Furthermore all agents share the same incentives. It is in every satellite operator's best interest to not pulverize their sat by an other one.
- Workaccount2 5y agoI think the concern is that some of those satellite operators might be totally subject to the will of some dumbass dictator or politician. I think of that Romanian dictator (Ceaușescu) who let his totally uneducated wife design the subway system in Bucharest. It was completely non-sensical, but the engineers had their hands tied (although they did secretly build stations in anticipation of common sense coming along at some point.)
- flerchin 5y agoKessler syndrome is a real thing, but this reads like FUD.
- dormento 5y agoMy layman's understanding makes me wonder if we could solve this situation with a big-ass magnet in orbit, to slowly eat the debris. OF course there would be complications from the simple fact that it would need to be very big, incredibly durable (as to not generate more debris itself), hard to launch (probably too heavy) and taken into account in all the calculations going forward.
- SonicScrub 5y agoUnfortunately it's not that simple. Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space. And the valuable space in orbit is no exception. Take the entire surface area of the Earth, and then extrude it up into a volume roughly 800km high. That's the volume you need to clear (and that's just Low Earth Orbit). There is no magnet powerful enough to make even a dent.
- Taylor_OD 5y agoYup. This is one of those issues where in most folks heads near by space/orbit is small in comparison to the vastness of space and the universe. Which it is. However its still incredibly massive and difficult to comprehend just how big it is.
- short_sells_poo 5y agoI wholly agree with the spirit of your post, but I thought LEO is not that problematic because there is still atmospheric drag there that will bring down rubbish in the matter of years.
- SonicScrub 5y agoWell the clean-up problem get's even more complicated with MEO and beyond as the amount of space becomes even larger. As for space-junk not being a problem in LEO, you are correct that space junk in LEO will de-orbit in a somewhat reasonable time-frame (on the order of a few years), but that's still problematic. It would still cause the destruction of 100s of billions of dollars worth of equipment, the ceasing of any operations dependent on LEO satellite equipment, and either increasing the risk or out-right blocking launches through LEO for a number of years. The fact that this would be temporary does not mean it isn't very bad.
- emtel 5y agoA sanguine take from Casey Handmer of the JPL: https://caseyhandmer.wordpress.com/2019/10/25/space-debris-probably-not-coming-to-a-backyard-near-you/amp/ https://caseyhandmer.wordpress.com/2019/10/25/space-debris-p...
- detritus 5y agoFascinating, thank you! The graded tungsten particulate cloud idea is particularly clever.
- cletus 5y agoHere's what I've learned: there is zero chance of the world uniting behind any cause. The solution to any of these problems will be economic and out of necessity and never because of altruism. Want to reduce fossil fuel usage? It'll only happen when cleaner alternatives are cheaper. Climate change? Nothing will change here until there's an economic reason for carbon sequestration. This may seem depressing but there's an important lesson here: any sense of urgency is almost always overblown. Things really do have a way of resolving themselves. Oh and as for space debris, yes it's a problem but space is also really big. Like the US also put a bunch of copper up in space [1] that's still there. How could this resolve itself? It'll end up resolving itself when launch costs are sufficiently cheap. We've made a ton of progress in the last few decades. IIRC SpaceX cost of getting payloads into LEO is like 20x cheaper than 20 years ago but it's still north of $1000/kg. But what does the situation look like when the cost gets below $10/kg? That's not as unrealistic as you may think. A lot of attention is given to space elevators. I think these are likely infeasible (eg they rely on discovering a sufficiently strong material that doesn't exist yet). But orbital rings [2]? These require no magical material and would be completely game-changing. If you have something like that just hang things off them to pick up passing space debris. [1]: https://www.wired.com/2013/08/project-west-ford/ https://www.wired.com/2013/08/project-west-ford/ [2]: https://www.youtube.com/watch?v=LMbI6sk-62E https://www.youtube.com/watch?v=LMbI6sk-62E
- celticninja 5y agoExcept the pandemic shows us that we can. It's not perfect but it was at least a good effort in terms of global cooperation. Bar a few outliers.
- cletus 5y agoHere's an alternative view: we may never reach herd immunity with Covid-19 and it may be something we just always have to deal with in large part because a significant percentage of the population won't get vaccinated because of side effects that, if they exist at all, are less than 1 in 1,000,000 likely to cause problems. A large number of people have shown they're quite willing to let millions of people die rather than do something that's less risky than taking a bath.
- BurningFrog 5y agoOne science fiction thought is that inducing Kessler Syndrome on Earth would be a perfect way for a Moon or Mars colony to "declare independence". If Earthlings can't get off the planet, it doesn't matter how much money, people and power they have.
- deleted 5y ago[deleted]
- hunterb123 5y ago> The Californian company SpaceX alone has launched some 1,700 satellites over the past 2 years as part of its Starlink network, which provides broadband Internet, with thousands more planned. None of which are high enough in orbit for this to be an issue. They have a lifespan of 5 years or so before they fall and burn up in the atmosphere. Why was it included in the article? In the first paragraph nonetheless. None of the other mega constellations are a problem either, they are mega constellations because they are in VLEO. You need more satellites to cover the Earth when they are lower, but they will also all fall back down, posing no long term threat. Either the author is unaware of what he is writing about, or has malicious intent, either way, it doesn't instill trust in the article if there's no distinction of which type of orbit the satellite is in. Sure we should be careful with satellites in more fixed positions, but the top paragraph seems like a hit piece against SpaceX, and slightly against the other companies wanting to do satellite constellations (although no name drop)
- z3rgl1ng 5y agoPeriodic reminder that Starlink’s 12k cluster will only support ~500k users[0] at a minimum $1bn cost to taxpayers[1]. [0] https://www.techdirt.com/articles/20200928/09175145397/report-notes-musks-starlink-wont-have-capacity-to-truly-disrupt-us-telecom.shtml https://www.techdirt.com/articles/20200928/09175145397/repor... [1] https://www.google.com/amp/s/www.cnbc.com/amp/2020/12/07/spacex-starlink-wins-nearly-900-million-in-fcc-subsidies-auction.html https://www.google.com/amp/s/www.cnbc.com/amp/2020/12/07/spa...
- hunterb123 5y agoI don't see how your FUD is relevant to this discussion of space debris, please stick to discussing the article. Please see other reply to you why those articles are FUD, they explained it much better than I could.
- z3rgl1ng 5y agoAh, the relevance is that SpaceX is producing a ton of extra objects in space.
- quadcore 5y agoThere is a YC startup from a recent batch that want to salvage and solve that.
- deleted 5y ago[deleted]
- thedudeabides5 5y agoSeems inevitably we'll eventually get unsustainable levels of junk up there. Anyone have creative ideas for how to clean all this crap up someday with "deep tech"?
- thedudeabides5 5y agoNope. The scions of HN went silent. Ok here's a random potential solution...how about weaponized satellites with the ability to generate electromagnetic fields which can force small junk into lower orbits. Is that a thing? Just a thought, not an astrophysicist.
- AndrewKemendo 5y agoAt this point I don't have much faith that there is any existential scenario that would unite the world in cooperation. The fact that this isn't existential or even comprehensible to lets say 80% of the world's population, tells me we as engineers and designers need to plan for our technologies to be able to operate despite an inevitable cascading space collision.
- scarecrowbob 5y agoI have a dumb Kessler syndrom question, but I don't really have the physics to answer it myself. I've been told that worrying about the longer-term implications of systems like Starlink aren't so terrifying because these satellites are in LEO. Specifically, the time for that kind of junk to de-orbit is on the order of 5 years, so the worst case scenario for this junk is to wait it out. However, if we get a good set of bouncing space junk, how does that affect this? The vectors generated from the parts two colliding small object might be in any direction, including outward? My physics isn't that great, so I am left with this question: is it worth thinking about the small bits of junk re-orbiting other junk? Would that push out the timeline of being able to simply wait out a incipient Kessler syndrome?
- beecafe 5y agoBasically when you modify an orbit with a single impulse - short rocket burn, bumping into something, etc - the resulting orbit will still intersect that point (unless you reach escape velocity). So those pieces should return to that piece of LEO, although they could still be spending large amounts of time far from there.
- TTPrograms 5y agoKerbal Space Program intuition tells me that the worst case is that you produce a high velocity piece of debris aligned perpendicular to radial vector, e.g. aligned with the existing orbit. I think this is a fairly unlikely direction to transfer energy in a head-on collision (by conservation of momentum arguments). That debris would then traverse a fairly elliptical orbit with frequent passes at the same altitude, likely resulting in relatively rapid de-orbit. The main risk would be inducing chain reaction at higher altitudes during those few passes, which seems unlikely. Any other debris trajectory induced by collision would hit lower altitudes in less than one orbit time (either going outwards and thus on a much more eccentric orbit, resulting in lower altitude pass in less than one orbit time, or going inwards and immediately passing at lower altitudes). So that debris seems likely to deorbit even more quickly, indicating your intuition is correct. This all makes sense once you grok why craft need two separate boosts to transfer to a higher geocentric orbit. Of course there's a transition point where satellites are so dense that even these short-lived trajectories are sufficient to induce a self-maintaining chain reaction of debris. I suspect that's unlikely - the probability of a collision occurring in one or two orbital periods seems negligible.
- bawana 5y agoWhy is everyone worried about all that junk? It's reaction mass for getting out of orbit or getting back to earth. It's mostly aluminum which melts easy. Just build a solar furnace in space that has a big 'catcher'. Make aluminum ingots. And shoot them off a spaceship which has a giant electromagnet. As you know, pulsing the electromagnet creates eddy current in the aluminum. This force has been used to weld metal https://www.tandfonline.com/doi/abs/10.1080/09507119809452024 https://www.tandfonline.com/doi/abs/10.1080/0950711980945202... The ingots fly back to earth and burn up in the atmosphere.
- munk-a 5y agoI think the issue is that actually collecting all those bits (if we needed to quickly clean up our orbits) would be extremely expensive. You'll need to adjust delta-v hundreds of times to match orbit and collect all these bits and pieces. Basically - imagine dusting your place - except you're doing it in a car and you need to stop precisely over each dust mote to collect it. You're going to waste a whole lot of effort on manuvering and what to do with the junk once you've got it is actually a relatively simple problem[1]. 1. You probably want to consolidate all the little bits of junk into one big bit of junk that, at some point in the future, you can scrap for orbital construction.
- bawana 5y agoWow, that's a great problem. Imagine putting up 10 junk collectors the consist of solar panels a super capacitor and a giant electromagnet-all bundled up in a little space drone. The earth tracks garbage maneuvers the drone near the orbital path of the junk, and when the junk comes close pulses the magnet. The junk decelerates, the drone accelerates and then eventually merge orbits. Junk captured. Onto the next one. As most of the acceleration and deceleration is provided by the kinetic energy of the space junk, the drone needs very little reaction mass as it only has to adjust its angular momentum now and then.
- thangalin 5y agoStars in the Milky Way form a pancake-like disc 120,000 light-years across. In ~80 years our fastest space ships will hurl along around 900,000 kilometres per hour, assuming they can leave orbit. ;-) That makes 144 million years to travel across the galaxy. Now space-faring peoples probably won't have evolved near the disc's edge. So let's say it takes about 100 million years to fan out and colonize most of the galaxy's habitable planets. Our one data point on technologically advanced life indicates 4.5 billion years for it to find a foothold after the dawn of a new solar system. Depending on the values you put into an E.T. calculator[1], there are between 4 and ~200 advanced alien civilizations loitering about. We know of many Sun-like stars that are ten billion years old in the Milky Way, twice as ancient as our star. One hundred million years barely registers on either a 5.5 or a 10 billion year scale. That scale affords aliens an enormous amount of time to have sown their seeds. Hence Fermi's Paradox and hence why a Kessler Cascade setback would be a footnote's footnote on these timescales. In short, a Kessler Cascade is important to avoid, but doesn't resolve Fermi's Paradox (it isn't a Great Filter). [1]: https://www.omnicalculator.com/physics/alien-civilization https://www.omnicalculator.com/physics/alien-civilization P.S. I describe a novel solution for Fermi's Paradox in my hard sci-fi book. Am looking for beta readers; see my profile for contact details.
- twirlock 5y agoI'll start giving a shit about chicken little science again when world leaders stop conspicuously withholding real information from the public. If we're hearing about it, it's a marketing campaign with an ulterior motive. Wake me up, for instance, when someone wants to explain the UFOs harrassing militaries. Why would I even read this article? I do not fucking care.