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Sad Trombone Exoplanet Reality Check
- lmm 10y agoIt's disingenuous to talk about Fukushima as a "meltdown", or imply that it was dangerous (on the scale of space-travel dangers). The Project Orion design was for 10% of light speed, and didn't assume any scientific breakthroughs like fusion - it would require a massive amount of engineering , but the core technology (that used in nuclear weapons) was mature in the '70s. We're still talking about a 40+ year journey, for a craft whose cost was estimated at $367B at the time - about $2.5T now. It's not easy by any means. But it is doable. We'll get there.
- creshal 10y ago> a craft whose cost was estimated at $367B at the time - about $2.5T now. So we can pay for it with just the money mismanaged by the US armed forces.
- aetherson 10y agoNo you can't, Jesus, read the actual article. The entire yearly budget for the US armed forces is around $600 billion. They had $2.5 trillion in adjustment lines that mostly netted out, they didn't actually lose track of $2.5 trillion, because they didn't have $2.5 trillion to lose track of.
- creshal 10y ago> The entire yearly budget for the US armed forces is around $600 billion. Oh, only. My point still stands: 2.5T isn't that much for a project at a national, or even global, scale. A mere ten times ISS and ITER and LHC combined? Absolutely doable.
- tptacek 10y agoNo part of your original point appears to have survived that rebuttal.
- Houshalter 10y agoThat's a yearly budget though. This craft could be built over many years, so the comparison makes a bit more sense.
- creshal 10y agoIt would be built over several years anyway, you can't get a project of that scale done and ready in a year.
- madaxe_again 10y agoOr just repurpose the incredibly expensive relict stockpile of nukes, which is where most of the cost sits. The tricky bit is reliably getting hundreds of tonnes of thermonuclear goodness into orbit without a single accident, which is why Orion died a death.
- GunboatDiplomat 10y agoWell, you just launch them on one Orion-drive space ship. A few dozen nukes to get it into orbit probably will only cause a few dozen cancer cases, if you do it right.
- throwaway7312 10y agoWe'd get there even faster with the money mismanaged by the US welfare system. Armed forces is only 23% of the US federal budget. Welfare's a whopping 40%. Of course, without American armed forces and the Pax Americana, the unprecedented world peace (relatively speaking) we have right now likely would not endure. And without welfare spending, morale would decline when old people and children that didn't need to die do. Both outcomes would likely lead to economic decline. Then we might not get there so fast after all. Sometimes the expedient-seeming solution isn't always the best one.
- riffraff 10y agoremember the US military expenditure is almost the total sum of the next 14 countries, 12 of which are allies. I'm sure the "pax americana" would hold with some cuts.
- vonmoltke 10y agoArguably those twelve allies have such low budgets because the US budget is so high.
- creshal 10y ago> Of course, without American armed forces and the Pax Americana I didn't know that mismanagement and embezzlement of funds was a vital core aspect of the Pax Americana. Similarly, the US health care system is about twice as expensive as comparable foreign systems for the same level of service provided. You can reform it and make it more efficient without compromising its mission.
- hatsunearu 10y agoHow is it disingenuous? Or is it more accurate to call Fukushima a dirty bomb that spread nuclear material all over Japan because of idiotic politicians?
- vonmoltke 10y agoThat would be less accurate, because it wasn't (except in the minds of the idiotic politicians who fed the hysteria over radiation).
- dredmorbius 10y agoOnly if stating the true facts as reported by the Nuclear Energy Agency is "disingenuous". On 17 May, analyses performed by TEPCO indicate that significant fuel melting occurred in the unit 1 reactor core with relocation of molten fuel to the lower portion of the reactor vessel. Further, the high-temperature molten fuel (greater than 2 800°C) appears to have caused small leaks in the lower head of the reactor pressure vessel.... On 7 June 2011, the Government of Japan releases a report prepared by the Government Nuclear Emergency Response Headquarters for the IAEA Ministerial Conference on Nuclear Safety (20-24 June 2011, Vienna, Austria). This report includes analyses of the damage to the cores at units 1 to 3. The analyses show that unit 1 has suffered extensive fuel melting and that the reactor pressure vessel has been breached. http://www.oecd-nea.org/news/2011/NEWS-04.html http://www.oecd-nea.org/news/2011/NEWS-04.html Multiple additional reports, totalling about 50: http://www.nrc.gov/site-help/search.html?q=fukushima+meltdown&site=allSites#gsc.tab=0&gsc.q=fukushima%20meltdown&gsc.page=1 http://www.nrc.gov/site-help/search.html?q=fukushima+meltdow... Or: 1. Introduction The triple core meltdown at Fukushima Dai-ichi power plant on March 11, 2011 is the worst nuclear catastrophe after Chernobyl in 1986. The substantial losses of this accident have aroused in the public opinion an old age debate: Is nuclear power safe? Safety Science April 2014, Vol.64:90–98, doi:10.1016/j.ssci.2013.11.017 How Fukushima Dai-ichi core meltdown changed the probability of nuclear accidents? Lina Escobar RangelFrançois Lévêque http://www.sciencedirect.com/science/article/pii/S0925753513002816 http://www.sciencedirect.com/science/article/pii/S0925753513... Or: Journal of Nuclear Science and Technology Volume 49, 2012 - Issue 1 "Analyses of core melt and re-melt in the Fukushima Daiichi nuclear reactors Fukushima NPP Accident Related" Fumiya Tanabe Page 18-36 | Received 11 Aug 2011, Accepted 16 Sep 2011, Published online: 24 Jan 2012 http://dx.doi.org/10.1080/18811248.2011.636537 http://dx.doi.org/10.1080/18811248.2011.636537 Abstract: Analyses are performed of the first core melt behavior of the Unit 1, Unit 2 and Unit 3 reactors of Fukushima Daiichi Nuclear Power Station on 11–15 March 2011 as well as the re-melt (melt again) behavior in another chaotic period of 19–31 March 2011. Analyses are based on a measured data investigation and a simple model calculation.I Keywords: core melt, re-melt, severe core damage, Fukushima, nuclear reactors, energy balance, zirconium steam reaction, hydrogen generation, core materials inventory, core water level A Google Scholar search turns up over 9,000 similar results: https://scholar.google.com/scholar?start=10&q=fukushima+core+(melt%7Cmeltdown)&hl=en&as_sdt=0,39 https://scholar.google.com/scholar?start=10&q=fukushima+core... Please do not spread disinformation.
- douche 10y agoThe physics of space travel are harsh, and the distances involved even harsher. Plus, unless you want to go screaming by on a fly-by mission, you have to burn all that delta-V you generated to get there in order to slow down again. The only real solution will be some kind of essentially magical faster than light technology - never say never, but it doesn't seem likely without some staggering breakthroughs in areas of physics we don't even have an inkling about. Maybe it's the American exceptionalism and internalization of Manifest Destiny as the natural order of things, but the idea of being effectively stuck, as a species, on this one rock for eternity is pretty depressing. Especially if that is the fate, not just of ourselves, but of all life intelligent enough to look up at the stars and imagine walking among them. If the best we can hope for is a Motey-like[1] Malthusian cycle, it's not much to look forward to. [1]http://amzn.to/2b5I0Ea http://amzn.to/2b5I0Ea
- white-flame 10y agoBasically wormholes/hyperspace/teleportation, or bust. But I'd think living in orbital or interplanetary space right here in our solar system can be a happy medium, and sustain us for a loooong time to come.
- raverbashing 10y agoOr just build a big ship and send it with settlers. If it takes 1000 years that's fine
- judofyr 10y agoIsn't "a ship where we can live for 1000 years" just the same as a planet?
- d0m 10y agoYeah, maybe the next big thing isn't travelling to a far away planet but just creating a ship big enough. I had a pretty cool theory about that when I was a kid, funny to see that it may be what actually happens.
- deanCommie 10y agoWhen I was a boy in the Soviet Union in the late 80's, I picked up a book on computers. It was targeted towards children, and talked about a lot of different components and ideas from bits and bytes to RAM to networking, and interesting applications like barcodes. I remember my mind being blown by barcodes. But the idea seemed far-fetched and unrealistic. To put a barcode on EVERY single item in the grocery store? That would take decades to implement! Then we emigrated to Canada and I was shocked to see it was already in place (and must have been for a while). Maybe this isn't the best example of tremendous human achievement but it taught me to not take for granted what is unrealistic and how quickly humanity could achieve it if we put our minds to it. With apologies to Cliff Stoll and his magnificent brain, let's not forget a pretty common perspective on the Internet from 1995: http://europe.newsweek.com/clifford-stoll-why-web-wont-be-nirvana-185306?rm=eu http://europe.newsweek.com/clifford-stoll-why-web-wont-be-ni... Space exploration and rocketry is not cheap, and requires new innovation. Only SpaceX is doing anything on that front. But if humanity set getting to Proxima Centauri as a goal, I have no doubt we could achieve at least kicking off a single-generation journey within my lifetime (ie sub-80 year journey time in the next 80 years)
- digi_owl 10y agoEffectively, what we need to do is to get some kind of space resource rush going. Similar to what fueled the likes of the East India Company.
- dalke 10y agoYes, if only Mars were already settled and we could exploit the people there. The question has always been what resource, with 3He and platinum being the two main contenders. Otherwise, it could be like coal mining in Antarctica, or manganese module mining from the deep seafloor - technically possible, but not profitable, and certainly not enough for a new EIC.
- JumpCrisscross 10y ago> what resource Ideas. That crazy nuclear experiment you want to run? Fat chance in Montana. But on the far side of Mars? Why not.
- StreamBright 10y agoExcellent read, so much insight. We really need those gates from "The Expanse" series.
- DanBC 10y ago> Currently, the most distant visited body in the solar system is Pluto, at 7.5 billion kilometers. The New Horizons probe flew past Pluto on July 14, 2015. It was launched on January 19th 2006 by a booster and upper stage combination that blasted it straight up to solar escape velocity, with a speed of 16.26 km/sec (58,536 km/h), making it the fastest human-made vehicle ever: it then executed a Jupiter gravity-assist flyby to slingshot it out past Pluto, where it arrived nine and a half years after departure. Lots of people have no clue just how big the solar system is, and how small the planets are in comparison. (Never mind the distance to exoplanets). Here's one video that gives a nice demonstration using a soccer ball and pin heads, from Mark Rober (who worked on a Mars rover at Nasa): https://www.youtube.com/watch?v=pR5VJo5ifdE https://www.youtube.com/watch?v=pR5VJo5ifdE
- swang 10y agoBill Nye demonstrated it pretty well on his tv show. Very easy for kids (including me when I first saw this) to comprehend. https://m.youtube.com/watch?v=97Ob0xR0Ut8 https://m.youtube.com/watch?v=97Ob0xR0Ut8
- digi_owl 10y agoThermodynamics is a real downer...
- Pxtl 10y agoImho the entropy laws are the real heartbreaker. They're the ones that explain how the universe doomed.
- dredmorbius 10y agoBut they're also the reason we're here in the first place. Shiva the destroyer, Brahma the creator, Vishnu the preserver.
- Synaesthesia 10y agoSame story for colonising Mars, or even sending astronauts there. It's pretty much unfeasible. Yes maybe we could send some people there but the costs involved are so astronomical that it really can't be justified. We're stuck on this planet and we need to make the best of it.
- Joof 10y agoAnd yet, two organizations have plans to do so in the next two decades.
- Synaesthesia 10y agoYeah a handful of astronauts can go there. But everybody else is stuck here.
- yen223 10y agoThere's a huge gulf between having plans to do something, and actually doing it. Moreso when that something has never been done before.
- exratione 10y agoFocusing on habitability from our perspective seems somewhat parochial. From the perspective of colonization: by the time future sentients descended from or created by present humanity get to other planetary systems, we-for-some-definition-of-we would be capable of living anywhere, and space and novelty will be things that you get by computing more efficiently, not by going places. From the perspective of adding data to the Fermi Paradox: assessing the possibilities of life being out there by looking for places in which bacteria of the known varieties could survive probably tells us little about the true range of life. From the perspective of resource assessment: by the time descendant entities get to other systems, it won't much matter how the matter there is distributed. It will used efficiently whether a gas disk, rock and ice condensations, or (improbably) somehow all in the star.
- Sharlin 10y agoInteresting that he doesn't mention the Breakthrough Starshot concept at all.
- mrfusion 10y agoVery interesting! https://en.m.wikipedia.org/wiki/Breakthrough_Starshot https://en.m.wikipedia.org/wiki/Breakthrough_Starshot
- Freaky 10y agoIt's mentioned in the comments: > As for the Starshot thing, that sounds like a reboot of Robert Forward's Starwhisp idea from the 1990s. The real problem with that is, how to get any data back from it. (Not to mention how to construct a continuously operating gigawatt laser array in space).
- deleted 10y ago[deleted]
- heisenbit 10y agoJust finished reading "The three body problem". A civilization on planet in a system with 3 suns would have some interesting challenges.
- mozumder 10y agoNASA should over the next 100 years build a hyper-telescope, so that people can begin to actually see these planets in detail before before a probe can be sent. Even with current technology, a hyper-telescope could be self-assembled in space, built from billions of 3-d printed & smoothened mirror segments, all aligned to half wavelength of visible light. We need to have a 1000px x 1000px resolution of earth-like planets out to 100 light years away, which would be several thousand miles in diameter.
- dredmorbius 10y agoThat's all but impossible. To optically resolve an Alpha Centauri planet of Earth size at Hubble resolutions of Pluto (about 680 pixels square) you'd need a 28 km wide scope (or array). https://www.quora.com/How-big-would-a-telescope-have-to-be-to-see-Kepler-452b https://www.quora.com/How-big-would-a-telescope-have-to-be-t... Rather than seeing shapes of objects, detecting their signatures -- light occlusion, spectroscopy, thermal and radio signatures -- is far more useful. Several of those would reveal chemistry and radiation indicative of life and/or intelligence. Much xenoplanetary analysis isn't done through optical telescopes, per se, but through spectrographic analysis, which tells us what compounds and elements are present (or are blocking / reradiating) starlight.
- DenisM 10y agoNothing wrong with a 28 km array though, if we can put it in space. Besides, what about dynamic aperture? I know very little about it, I only heard that a moving camera effectively expands it aperture by the distance traveled within the duration of the exposure.
- dredmorbius 10y agoYou're going to want _both_ light gathering _and_ range. Keep in mind, a planet is probably going to be moving a lot over the course of a few hours. A 24 hour time-lapse of the Earth will give you a lot of pretty colours. But not much by way of a useful image. You're trying to see something tiny and dim a very long way away, next to something which whilst also tiny (relative to the Universe) is far, far, far brighter. A long-duration moving-apature exposure of a remote planet next to a dim star seems to me not to be an ideal candidate for high-quality imaging. I'm not sure a large-baseline, large-collector array would do much better, but at least it could narrow the time interval somewhat. (Though I think you're still basically going to end up with a glared-out, underexposed, blurred pixel.)
- bogomipz 10y agoThe title of this blog post is one of the funniest I've read on HN, really made me laugh. The author states: "We might get a small probe up to arbitrarily high velocities if we cheat by using an engine that stays back home where we can keep it running, but then we run into other problems." Does anyone know which rocket propulsion technology he is referring to there? In the paragraph before he is referring to plasma beam but he doesn't say what this is.
- Symmetry 10y agoHere's the Wikipedia page: https://en.wikipedia.org/wiki/Magnetic_sail https://en.wikipedia.org/wiki/Magnetic_sail
- GunboatDiplomat 10y agoSome sort of light sail powered by a giant laser which we keep here.
- JumpCrisscross 10y agoProbably something similar to Breakthrough Starshot http://breakthroughinitiatives.org/Initiative/3 http://breakthroughinitiatives.org/Initiative/3
- TheOtherHobbes 10y agoThe goto site for discussions about interplanetary and interstellar anything is Centauri Dreams: http://www.centauri-dreams.org/ http://www.centauri-dreams.org/
- DenisM 10y agoMagBeam https://en.m.wikipedia.org/wiki/MagBeam https://en.m.wikipedia.org/wiki/MagBeam
- throwawaytire 10y agoThe title of this article sounds like a password [1]. Whenever one of these articles comes out I like to think of this fun paper: [2] Are Black Hole Starships Possible?", http://arxiv.org/pdf/0908.1803 http://arxiv.org/pdf/0908.1803 [1] https://xkcd.com/936/ https://xkcd.com/936/ [2] https://en.wikipedia.org/wiki/Black_hole_starship https://en.wikipedia.org/wiki/Black_hole_starship
- alanbernstein 10y ago> note that 4.25 light years isn't an order-of-magnitude improvement over the previous winners for Earthlike proximity, such as Wolf 1061c (13.8 light years away) or Kapteyn B* (12.76 light years away). We're talking about the difference between 40 arbitrarily-huge-units and 100 arbitrarily-huge-units. So how should we contextualize these arbitrarily-huge-units? This is nonsense. The point is that the exoplanet was (potentially) found orbiting the nearest star, which means it's as close as it can be.
- Udo 10y agoI wasn't aware this reality check was needed, but it's worth noting that we haven't even left Earth yet (going to the Moon doesn't really count, and we've since lost that capability again). If we were a solar-system-wide civilization, I can see how it would make sense to talk about the feasibilities of interstellar travel, but today we are so far off it's not even an issue. We also don't have any ambitions to change that, so extrapolating from today's state of affairs, we'll probably remain thoroughly Earth-bound until we reach a tech level that enables individual people to have space programs (if we ever get there). It's fun to think of probe-based exploration, but apart from acceleration/energy based problems we haven't even figured out how to make machines last that long. This is all very, very far off.
- jakub_h 10y ago> going to the Moon doesn't really count, and we've since lost that capability again What we've lost is will. The capability is definitely better today, even though still not affordable enough to fit today's budgets.
- deleted 10y ago[deleted]
- Houshalter 10y agoWell I think he means we couldn't just go to the moon next year, even if we wanted to. All the engineers and factories and equipment behind Apollo is scattered or lost. It would basically require starting a whole new moon program from scratch and designing and building entirely new spacecraft, etc.
- Udo 10y agoIndeed, yes, that's what I meant. But Jakub isn't wrong either, we lost the will too. But I thought I addressed that, but apparently not clearly enough.
- sklivvz1971 10y ago> 4.25 light years isn't an order-of-magnitude improvement over the previous winners for Earthlike proximity, such as Wolf 1061c (13.8 light years away) or Kapteyn B* (12.76 light years away). Wrong. It is, quite literally, just about a order of magnitude better.
- Sniffnoy 10y agoNote in the comments Peter Erwin points out that Charlie has overestimated the density in the (relevant portion of the) interstellar medium by several orders of magnitude: http://www.antipope.org/charlie/blog-static/2016/08/san-trombone-exoplanet-reality.html#comment-2008437 http://www.antipope.org/charlie/blog-static/2016/08/san-trom...
- bluejekyll 10y agoSo what you're saying is, "we need a bigger rocket!" I agree. It's high time we started on near light speed space travel.
- Pxtl 10y agoWe need cheap matter-energy conversion. Nothing less will provide enough energy for interstellar travel, and cheap matter-energy conversion may not be possible ever. Whether the engine is here or there, the amount of energy needed to launch a properly-radiation-shielded craft is simply obscene.
- makmanalp 10y ago> This veritable speed racer of an interplanetary probe would thus require a mere 31,600 years to reach Proxima Centauri (if indeed it was pointed in the right direction, which it isn't). Holy cow, that's multiple times longer than humanity has even existed as a civilization, and in all likelihood it might perish before that probe could even make it there. What a reality check. I don't think incremental improvements are going to cut it for space travel.
- a3n 10y agoSo we should send one out now, and hope we're still around when it gets there. And each time we complete development of something better send one of those. Can you imagine how pissed we'd be 31,000 years from now, not having sent whatever we finally determined to be the best we could do, when we could have done it? It may take N thousand years to get something there, but only four years to get data back. It's worth it.
- danbruc 10y agoDesigning a machine that still works in 31,600 years seems a pretty tough challenge. Even remembering to listen for a signal in 31,600 years is probably already a hard problem.
- a3n 10y ago> Designing a machine that still works in 31,600 years seems a pretty tough challenge. Good point. I'm quite sure we can already point something somewhere and it'll get there, or close, in 31K years. So the real challenge is what you point out. And remembering is maybe even more challenging. So the first one out ought to be very simple. Maybe it just pings home every N days. That would mean that we'd start out listening for it, and perhaps that infrastructure would be taken care of. And maybe that first one would die before it arrives. But if we continue to send something better each time we're able, I think we'd eventually have success. And if we do continue to send things, maybe we'd have an institutional tradition of listening for the original.
- JumpCrisscross 10y agoSounds like a riveting to-do list, with lots of big implications for the folks back home. > We'd need a whole raft of breathroughs, including radiation shielding techniques to kick the interstellar medium out of the way of the probe Game changer for nuclear power and propulsion, in terms of safety. If we did this with matter, that means we can get closer to hot things [1]. If we did this with energy, ha! - we can now start harvesting edge-of-magnetosphere antimatter and explore mining and terraforming using directed energy. > as well as some sort of beam propulsion system If we can beam massive amounts of power out that means we (a) have massive amounts of power up there and (b) can beam (a) home [2]. > and then some way of getting data back home across interstellar distances Either we figured out how to keep lasers (or some other stream of stuff) columnar over super-long distances or we broke new ground in information theory. Either way, getting a grainy picture home from Proxima Centauri on an apple of an energy budget means getting lots more closer to home around faster and more efficiently. [1] https://en.wikipedia.org/wiki/Star_lifting https://en.wikipedia.org/wiki/Star_lifting [2] https://en.wikipedia.org/wiki/Dyson_sphere https://en.wikipedia.org/wiki/Dyson_sphere
- mcguire 10y agoBah! That's an engineering problem.
- intrasight 10y agoI don't understand the focus of the article being on sending a physical probe. Why not just send a radio message? Something like "Is there anybody out there?" I've heard the argument that we shouldn't advertise our existence in case there are hostile beings. But can't we assume that all intelligent life is constrained by the same rules of physics? And why assume hostile?
- scott_karana 10y agoThe round trip time for such a message would be 9.0 year, so getting our signal discovered, and getting it mutually intelligible, could easily never happen, even if there was life there.
- dredmorbius 10y agoClearly, part of the trick would be to figure out what to send, and to keep sending it. Well, that, and figuring out how to send it. Though when you've got the resources of a habitable planet at your back, generating strong signals seems more viable.
- mjsweet 10y agoWhen I read articles like this, I like to imagine that we are already on a multi-generational ship (earth) and are on our way to see the wonders of the Andromeda Galaxy :)
- FiatLuxDave 10y agoI know Charlie is a writer, not a radiation physicist, nevertheless... major 'units' fail in his radiation calculation. 6 Trillion alpha particles per sq meter per second is 6 TBq per m^2; not 6 Tbq per m^2 per second. TBq as a unit already includes the "per second". In other words, you wouldn't get a Fukushima release every eight days - you'd just get about 1 millionth of a Fukushima... and that's it (per m^2, of course), as long as you are moving through an interstellar medium as thick as he posits at that speed. 160 Curies is a dangerous amount of radioactivity, but nothing outrageous. I often work with gamma sources much larger than that. I use a 1000 Curie source that easily fits in a sq meter, and it's used the same shielding for over 20 years.