12 ms·
"just 12 light-years away" I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology
by petercooper 7y ago
"just 12 light-years away"
I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-)
- TeMPOraL 7y agoAnd "just" 24 years over radio if there's anyone there to talk with ;).
- petercooper 7y agoI doubt I'm alone in this, but I do find it simultaneously amusing and depressing how mind bogglingly big the universe (or even the galaxy) is. It's clear that discovering entirely new levels of physics will be necessary to stand a chance of going anywhere.
- api 7y agoOr extreme life extension, or fully digital AI. Life span is a big part of the problem. Personally I doubt that meat will go to the stars. Planets, sure, and maybe bases or settlements. The stars take too long.
- TeMPOraL 7y agoYou're not alone. I grew up reading and watching a lot of sci-fi. Today I recognize that most of it was garbage in terms of physics, but I'm still saddened that the universe isn't that easy - we can't just hop on a space cruise ship and do a tour of a nearby nebula...
- pault 7y agoGoing to Mars may be routine some day, though!
- ekianjo 7y agoJust going to Mars will significantly increase your risk of cancer, unless we find smart ways to repair our genetic material as we go.
- gambiting 7y agoWell, for the journey itself the problem has a simple solution - more shielding. Then of course we have to answer the question of how can we get ships into orbit when they are full of shielding, but that's not insurmountable. The bigger issue is actually living on mars - as romantic as that idea is, human habitation on the surface is really dumb, the radiation level is not insignificant, so anything long term would either have to be shielded or be under ground. And if we are going to build an underground colony....then why not start with one here on Earth?
- cygx 7y agoThen of course we have to answer the question of how can we get ships into orbit when they are full of shielding, but that's not insurmountable. If regular travel becomes a reality, you wouldn't shield the launch vehicle, but the cycler[1]. [1] https://en.wikipedia.org/wiki/Mars_cycler https://en.wikipedia.org/wiki/Mars_cycler
- isostatic 7y agoThe benefit of using a cycler rather than a ship that travels orbit-to-orbit is that there is no need to accelerate/decelerate the mass of the ship, just the perishables (people and provisions for the voyage) You would accelerate a small vessel (like a crew dragon or orion), intercept and dock with the much larger cycler, then enter the ship for your x-month trip. When you near mars, you get back into your dragon, and burn away from the cycler, entering into martian approach. 7 people in a Crew Dragon for 18-24 months would not be pleasant. 7 people in a flying space hotel would be far nicer. You could presumably look at using a small asteroid to provide the bulk of the "cycler", offering plenty of shielding for the trip, you'd only have to get it into position once - far less fuel requirement. My understanding though is Musk is planning on using BFR to go surface-to-surface, with maybe a refuel in earth orbit. I believe this is because of the amount of material that needs transporting to Mars for the first 20 years or so, and that mass can be used as useful shielding. Even if Mars becomes self sustaining and doesn't require a large amount of cargo:people ratio, I believe Musk is aiming for a much shorter transit time than 2 years.
- dekhn 7y agoyou are not alone
- Evidlo 7y agoCount your blessings. The vast separation between stars means that star systems can have stable planetary orbits for billions of years, which is important for life to develop.
- riffraff 7y agoI've read that most of Lovecraft's is derived from the horror at realizing how insanely large in both space and time the universe is. The unspeakable horrors and mind defying deities in his oeuvre are effectively just reiteration of the "the human race is an irrelevant blip on the universe's radar" concept.
- programd 7y agoWell that just cries out for a quote :) "We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age." - H.P. Lovecraft "The Call of Cthulhu"
- riffraff 7y agobeautiful, thank you!
- tim333 7y agoOr entirely new levels of lifespan. Just upload yourself to the grid and boot up in a few million years.
- 40four 7y agoWhy 24 years? Radio travels at the speed of light, not half the speed of light, right?
- adrianN 7y agoRoundtrip time.
- 40four 7y agoHAHA! Thanks, sometimes I need a kick in the rear. I was thinking one way.
- dudemcbacon 7y agoAny response would take 12 years as well.
- deleted 7y ago[deleted]
- cptaj 7y agoTo me this sounds feasible. We already organize space missions over the 20 year mark. Communicating effectively with another civilization could be taken just as seriously and done in an organized and effective manner. It would take a while to get going but once the sharing starts it would be immensely productive.
- lmm 7y ago> I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-) If we had the political will, the Orion design could get people there in, what, 200 years, and that's with '70s technology.
- acidburnNSA 7y agoAre you talking about the propulsion system where a series of nuclear explosions push the vessel along? https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...
- tictoc 7y agoImagine being the child born on the ship on a crash course to this new planet.
- api 7y agoLook into Project Orion. With thermonuclear bombs you could hit 8% c, which would get you there in "only" 150-200 years including acceleration and deceleration time. That is still beyond humans with present day life spans, but extend life span to ~1000 years or go full AI and you can totally ride the "devil's pogo stick" to stars <=20ly or so awat. Fusion rockets would probably be better. I mention Orion because we sort of know how to build it today... at ludicrous cost. No new physics and not that much fundamentally new engineering is needed. Orion is a fabulous and quite valid counter to the folks that seem to like to repeat the canard that interstellar flight is impossible. Hard as hell, sure, but not impossible by any means. To a fully Kardashev type I civilization it might be around Apollo moon shot difficulty.
- bencollier49 7y agoIs that subjective time for the crew or objective time? Is there much of a difference at 8% c?
- simonh 7y ago>Orion is a fabulous and quite valid counter to the folks that seem to like to repeat the canard that interstellar flight is impossible. I’d never say it’s impossible, if we maintain a civilisation for long enough it might even be inevitable at least at a minimal level. However, Daedalus/Orion is far from as straightforward as has been suggested by you and others. It’s based on projections of technology made in the 70s, not 70s technology. There are also formidable obstacles, such as obtaining enough Helium3. The authors suggested extracting it from the atmosphere of Jupiter or Uranus. That by itself would be as hard as building the vehicle itself, if not harder. I’d like to see a design for a Jupiter atmospheric scoop and return vehicle. Also Daedalus couldn’t take people. Staggeringly huge as it was, it was a flyby mission with a 450 ton payload. If it was going to decelerate instead it’s payload was about the size of a washing machine.
- sametmax 7y agoI smiled as well but with a slowly but steadily accelerating ship we can reach half the light speed and get there in 50 years. It put things in the realm of "possible" which is amazing.
- deleted 7y ago[deleted]
- gameswithgo 7y agonow do some napkin math on the reaction mass and energy you need to slowly accelerate that much for that long
- jniedrauer 7y agoAnd the energy transferred by an impact with a piece of dust at luminal speeds
- interfixus 7y agoNow do some napkin math on the amount of gears and levers you need to reach such calculating power, mr. Babbage.
- loteck 7y agodon't forget, you're going to have to slow down at some point, too
- carapace 7y agohttps://en.wikipedia.org/wiki/Torchship https://en.wikipedia.org/wiki/Torchship > Torchship (or torch ship) is a term used by Robert A. Heinlein in several of his science fiction novels and short stories to describe fictional rocket ships that can maintain high accelerations indefinitely, thus approaching the speed of light. The term has subsequently been used by other authors to describe similar kinds of fictional spaceships.
- Eupolemos 7y agoI think current technology makes no sense when talking about interstellar travel. I wonder how long it'd take, seen from the perspective of the ship, if we had an engine capable of delivering a constant 1g acceleration. That's the way we'll want to travel, after all.
- superpermutat0r 7y agoconstant 1g acceleration gets you to speed of light pretty quickly (around 1 year), so still around 12 years.
- deleted 7y ago[deleted]
- Someone 7y agoIf our current ideas about physics are correct, acceleration _never_ gets you to speed of light. The faster you go, the higher your relativistic mass, so if you accelerate by constant force, the lower your acceleration. Conversely, to keep acceleration constant, you would need larger and larger forces, in the limit ‘infinite force’. For more and better info, see https://en.wikipedia.org/wiki/Space_travel_using_constant_acceleration https://en.wikipedia.org/wiki/Space_travel_using_constant_ac....
- pdonis 7y ago> The faster you go, the higher your relativistic mass, so if you accelerate by constant force, the lower your acceleration. The Wikipedia article you linked to calls this (rightly) a "half-myth". It depends on your reference frame.
- 4bpp 7y agoAs far as I understand, viewed from Earth's reference frame, a spaceship accelerating by constant force will get heavier and heavier as it gets faster, and thus get less and less speed out of it, asymptotically approaching the speed of light but never exceeding it. Moreover, crucially, any pingbacks from clocks on the spaceship we observe will appear to be progressively going slower than they should. (Time dilation) The spaceship's own reference frame will be a whole different story. If I understand correctly, it will perceive its own mass to be constant, the rest of the universe's relative speed to asymptotically approach the speed of light, but also the rest of the universe to get progressively squashed in the direction of travel (length contraction dual to time dilation), with the two effects multiplying up in such a fashion that the Newtonian relation between the integral of your acceleration and the time it takes to the destination seems to hold throughout. In other words, for the spacefarer's schedule, it's as if the speed of light does not actually play a role: they can always accelerate more/go arbitrarily faster to get to their destination faster. However, from their point of view, it is as if the universe around them will deform in the process to accommodate this, and from the stationary observer's point of view, it is as if they are actually still moving slowly but tricking themselves into thinking otherwise by accelerating their passage of time.
- burtonator 7y agoBy way of comparison the entire 'human'species is about that age. += 250-500k years depending on how you measure. Honestly it's far far far better to focus on reaching superhuman intelligence and AGI and then just creating a Dyson sphere around our sun. At that point we can try to figure out FTL travel...
- morsmodr 7y agoThis! If you look at all the life on Earth, humans are the only ones to have maximized brain functionality and evolved to change their surroundings on a global scale. We should continue focusing on superhuman intelligence and AGI which will solve problems that we cannot simply right now due to our evolutionary limit at this point in time.
- ggggtez 7y agoNo, it's 12 years away by radio wave, which means 24 years for a round trip communication. Physical travel is out of scope, but we could share knowledge in the (extremely) unlikely case that we found intelligent life with radio technology.
- Nelson69 7y agoIf we were to realize Breakthrough Starshot, then it'd be right around the cusp of how long I'd think we could maintain institutional interest in it. 60 years to get there, 12 years to get the signals back, so 76 years. If you worked on it right out of college and longevity stays around where it is, you might live to see some pictures. You definitely could tell your grand kids about it though. It seems technically possible, it is just a matter of paying for something like this and pinning hopes on the next generations to follow through with it and appreciate it. It seems like if we had that sort of will, climate change and some other issues would almost be non-issues.
- deleted 7y ago[deleted]
- agumonkey 7y agolet's see if someone will try to upsell the Musk
- hanoz 7y agoTo give a sense of the scales involved - if the sun were an orange and the earth a grain of sand 6 meters away, this star would be a pea about 5000km away. There would only be another 34 stars / fruit-and-veg within this 10000km wide sphere. It's pretty empty out there!
- booleandilemma 7y agoI’m amazed that the specks on the grain of sand can even be aware of the pea that’s 5000km away in the first place.
- trhway 7y ago>450,000 Earth years away with current technology With current tech spread thinly an alpha emitter like Po (2% mass ejected at 5% c) on the backplate and you’ll get 100km/s with 10% payload. Adding an electromagnetic “nozzle” to axially redirect sideway alphas would make it past 200km/s, ie. less then 20k years. Spread thinly enough for the decay leftover - Pb - to be ejected too and you can get to something like 600 km/s, just 6000 years.
- joshlegs 7y agothere is an effort to put super mini spaceships on missions to other solar systems, and they would travel at something like 20% the speed of light. I think it works by having the probes be like the size of a cellphone or something, and being attached to a solar sail, then using an incredibly high powered laser to pump the solar sail full of energy to get it going so fast. I think if that architecture works they could reach ... proxima centauri? ... in something like 20 years. just pointing that out to say that i think we have technology that would take less time than 450k years :)
- bdamm 7y agoHowever, a transmitter with enough power to signal earth would be too massive to get fast with a solar sail, given today's technology. Maybe a chipsat gets to 20% c, but no way a dish does.
- joshlegs 7y agoFound the wiki page for the project: https://en.wikipedia.org/wiki/Breakthrough_Starshot https://en.wikipedia.org/wiki/Breakthrough_Starshot so it looks like they'd want to launch by 2036. In the 'technical challenges' section, it does mention that some technologies would have to be miniaturized sufficiently, but it doesnt really mention much about whether that technology has reached viable stages or not, or whether it's a realm they'd have to specifically research further. So I guess maybe the technology doesn't exist today? Sounds like probably not, but maybe the near future -- or at least they expect it to exist by 2036. It's worth noting this project has backing by some pretty influential folks, including Stephen Hawking when he was still alive.
- Teever 7y agoWhat if the chipsat sends the signal to the chipsat behind it which sends the signal to the chipsat behind it which.... So that the signal can be relayed by a bunch of short range transmitters all the way back to earth
- aaronax 7y ago
- lelima 7y agoTime for the travelers will go slower, for earth time will be 450k years but for travelers will be less. Can someone explain this situation, what if the travelers reach almost speed light, they will reach on 12 years from earth perspective but for them how long will it take?
- bradenb 7y agoI believe the problem is that with current technology it isn't realistic to expect to accelerate continuously to a fraction of light speed where time dilation will be noticeable. We lack the ability to get a large enough amount of fuel off the planet and we obviously can't decelerate to harvest more fuel on the way there because then we lose the benefits of the continuous acceleration. EDIT: I wonder how feasible it would be to gather a large enough store of fuel from asteroids or comets before even beginning acceleration. You'd likely have to do it both ways which may make it a one-way trip if the destination doesn't have the necessary resources. The only way I'm aware of that we could power a long-running acceleration is via a nuclear-powered ion drive. But I don't believe the acceleration is great enough to make a dent in approaching the fraction of the speed of light we need for such a journey in a human lifetime. Please someone correct me if I'm wrong. I'd love to be wrong.