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NASA Begins Planning For An Interstellar Mission In 2069 (nypost.com)
Long-time Slashdot reader cold fjord writes:
During the 2017 Geophysical Union Conference, scientists from NASA's Jet Propulsion Laboratory revealed that they are planning an interstellar exploration mission for the year 2069. The goal is to send a probe to Alpha Centauri, some 4.3 light years away. NASA is working on technology to allow a spacecraft to reach 10% of the speed of light, which might allow them to reach Alpha Centauri in as soon as 44 years.
A number of technologies are being explored, although there are many practical hurdles. The New Scientist adds that the 2016 NASA budget directed NASA to study interstellar travel that could reach 10% of the speed of light by 2069.
A number of technologies are being explored, although there are many practical hurdles. The New Scientist adds that the 2016 NASA budget directed NASA to study interstellar travel that could reach 10% of the speed of light by 2069.
Fifty years is a long time. And with an ion engine, we would only need ~10^35000 kg of propellant!
Well one wishes them the best of luck, but it seems to me that going fast enough is only a tiny part of their problems and that getting any sort of useful communications back again is a least as big a challenge.
Consider the New Horizons mission to Pluto. The spacecraft is large and has a big high gain antenna. Also, it's power source hasn't been sitting around for 44 years. Never the less, data returns to earth at a few hundred bits per second.
Now consider Alpha Centauri. My quick calculations suggest that it is about 7000 times as far away (can someone confirm that?). Applying the inverse square law gives us a received power level - assuming the same transmit power and antennas - which is 77 dB (49000000 times) lower. Now, I am not saying that it can't be done, and I am sure that NASA have lots of very clever people, but as someone who has spend his career in radio and radar, finding an extra 77 dB is a very challenging requirement!
I bet your fun at partys.
I mean the tech certainly doesn't exist now.
But, with the advent of practical quantum computing, I would hope a lot of the math involved would become possible, unlocking more than just fusion.
Fusion drives are actually quite a reasonable technological development to anticipate in the (relatively) near future. It's over-unity fusion we can't manage to crack. I also suspect we never will, and that only gravity can do it on a practical basis, but that's just an ignorant layman guess.
As long as you're not worried about a net energy gain, and you just want what is basically a particle beam created by a poorly confined fusion reaction, a fusion drive appears doable and the math says it'll give you about twice the velocity of a nuclear pulse drive.
After that... it's pipe dreams about micro probes riding massive solar sails and somehow managing to carry useful instrumentation and a strong communication laser.
On your mark... get set... GO!
[($)]
First, warp drives do not exist (yet). You cannot instantly jump to 10% the speed of light and spend 44 years coasting to Alpha Centauri. To travel 4.3 light years with a constantly accelerating technology would require you to hit 20% the speed of light, not 10%. If you constantly accelerate up to 10% the speed of light by the time you reach the destination, then it'll take you 87 years to traverse 4.367 light years, not 44 years.
Second, you don't want to be accelerating the entire trip. Otherwise once you reach the destination, you're traveling way too fast for the trip to be of any use. Assuming the Alpha Centauri system is about the same size as our solar system, a probe reaching it at 20% the speed of light would pass through the entire system in a little over a day. It's stupid to travel 44 years just to have one day of science gathering. To be useful, you need to accelerate to the halfway point, the decelerate to the destination.
This means the trip of 44 years would require hitting 20% the speed of light by the halfway point - it would need twice the acceleration of a mission which hit 20% at the destination. So combined with the 10% vs 20% speed of light error, you actually need to develop a technology with 4x the acceleration of a mission which would arrive at Alpha Centuari at 10% the speed of light.
and the math says it'll give you about twice the velocity of a nuclear pulse drive.
Doesn't thermonuclear pulse drive already beat it?
Ezekiel 23:20
There is knowledge, and there is intelligence. Possession of the former is no guarantee of possessing the latter. You exemplify this in quite the Trumpian manner.
I'm holding out some hope that laser propelled microsatellites are feasible. If you fired a stream of them you could piggy back broadcasts between them back to earth, greatly reducing the distance each would need to transmit to get back home. You wouldn't need to slow down either, with a steady stream of small disposable craft.
You exemplify the worst of both ideologies: the blowhard bluster of Trumpian capitalism with the âoeI, the thinking elite, know better than you, dirt diggerâ of communism.
There's no way at all to build whatever you call a fusion drive.
I'm not aware of any theoretic obstacle yet, and as far as practical obstacles are concerned, I'm not saying that we'll be able to remove those but one can't say that we won't, either. At least not today.
What you see now as far as moving mass goes, is *it*.
What does that even mean?
Space is a dead end, no one is going anywhere.
That's provably false; there's cars outside my window going somewhere right now.
Ezekiel 23:20
speaking of grammar nazis
allow them to reach Alpha Centauri in as soon as 44 years.
As soon as 2113. Or, in as little as 44 years. That's how I would have written it. YMMV
Also Sieg Heil is the response. You initiate with Heil Hitler. Just sayin'
The communications technology to reach across 4.3 light years doesn't exist yet either. Look at the great lengths that we need to stay in touch with the Voyager aircraft just barely out of our solar system - launched 40 years ago.
And don't expect humans to survive all the hard radiation that's out there either. So it'd have to be a robot mission.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
Quantum entangled particles DO NOT permit sending of information faster than light. You still have to send a "light-like" signal to know the results of the entanglement.
What does a Boeing 747 from 1969 look like?
What does a Spitfire look like? HOW do we know we're a the Jumbo Jet phase instead of the Spitfire phase anyway? We don't!
Computers have gotten better by a factor of about a million in 30 years. A common "argument" from Space Nutters is "computers got better", as if that somehow means anything for moving mass.
Fortunately I haven't made that argument, like ever, not even a single time.
Space fantasies are for adults with the minds of children, or techno-atheists who think they're rational but embrace unscientific beliefs.
Ohhh, so I need to be religious now to be rational? :-p
Ezekiel 23:20
Unless the probe is able to withstand one hell of an acceleration outbound and isn't going to be in the Alpha Centauri system more than a few days.
And then they'll turn around because it's about time to brake for the next 50 years?
Santa travels at close to the speed of light and uses existing technology. Seems like that is the place to start. It does narrow the launch window as he is busy one day a year.
Accelerating any significant mass to .1c may be practically impossible. Perhaps the least unlikely approach, given our continuing miniaturization progress, is a spacecraft that weighs micrograms. Laser acceleration would seem to be an option, but the problem there is deceleration at the destination, and transmission of data back to Earth. What we really need is something super-light capable of using solar power to both accelerate and decelerate to a sizeable fraction of c, and then the transmission problem can be solved by having it make a return trip using the destination star for power.
The ultimate unrealistic extreme of this approach in sci-fi would be the sophons from Liu Cixin's The Three-Body Problem, which if I recall have the mass of one proton but unfold into useful spacecraft upon arrival.
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Such a thing would work in the inner solar system just fine. Basically, it would turn a 60% efficient electric rocket with an ion engine into, say, a "300%-efficient electric rocket". In fact, I've considered it in the past, but not for interstellar travel. For interstellar travel, which is the thing proposed in TFA, this wouldn't work and the fusion system would have to generate energy for its own re-ignition.
Ezekiel 23:20
Well, smaller more advanced computers add less mass to the load of a satellite, in addition to the greatly advanced computing power. This means that we are more capable of sending a space craft which can fly autonomously in a different solar system. Given the near decade a course correction from Earth would take.
Such a goal practically requires mastering nuclear fusion by that point in time.
Not really. The current leading contender for interstellar missions is a thumbnail-sized chip attached to a nanometers-thick light sail, and propelling that using ground-based lasers. That requires a lot of new technology, but power generation isn't one of them.
How do you get a signal back from a thumbnail sized chip? Even getting a signal across 4.4 light years from a full sized spaceship seems to be quite the challenge.
https://en.wikipedia.org/wiki/Inverted_totalitarianism
Like many other aspects of this scheme, that hasn't been worked out. One possibility that's been discussed is sending a train of these tiny spacecraft that relay the messages back in daisy chain fashion.
One possibility that's been discussed is sending a train of these tiny spacecraft that relay the messages back in daisy chain fashion.
A chain, yes, but the spacecraft are all launched at the same time, at varying speeds. Or maybe even some of the closer ones are launched earlier, however the math works out. And the ones meant to stay close to home will be larger, and capable of longer-range communication. It's not just a bridge, it's a pyramid, in a way.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Cyberspace is more promising anyway. No pesky c limits and such. Actual vulcans and a reset switch when the battle with the empire goes bad.
So it'd have to be a robot mission.
Duh. Both the summary and TFA make it clear that this would be a probe, not a manned mission. It would be a flyby, passing through the Alpha Centauri solar system in minutes, since slowing down and going into orbit would require exponentially more fuel. The proposals are for a probe the size of a pack of cigarettes, or even the size of a postage stamp, driven by a laser boosted sail.
The proposed budget is ~ $100M. A manned mission would cost many many trillions.
Bussard Ramjet? It's total Science Fantasy, but if we can manage to make a fusion reactor that works, we might be able to design a ramscoop for interstellar hydrogen and a magnetic constriction to force a fusion reaction to use for propulsion.
What planet are you on, where project Orion isn't already known to be fully capable of that right now!
We have build nukes. we have build small tactical warhead nukes. We have build a large lead plate with a hole. We have build shock absorbers that hold skyscrapers. We have built large rockets. We have had robots land by themselves on another planet.
It’s just a matter of combining those things in a very simple way. Simple math already tells us this will bring us to 10% speed of light. That’s not even with anything beyond 60s knowledge and ambition.
And a matter of having the will to plow through the small-minders and retards who believe that everything they can’t imagine cannot possibly be possible, let alone already done. (Kinda like doctors.)
If you could make the relays handle absurd G-forces, maybe you could detonate something between them in order to "drop them off" and also to provide more propulsion. But otherwise, how do you do that?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The plan is to use a laser boosted sail. No fusion needed.
The moon is not likely to be terraform-able. There is not likely to be much of a long term benefit to putting a man on the moon, unless the experiments conducted on ISS can be conducted in low gravity, or otherwise on the moon.
Building a base on the moon would delay us for decades, if not a century or two. And a mission to mars would only be slightly less risky from the limited knowledge gained from building a moon base as practice.
The moon has less gravity, which means softer landings. The moon has no atmosphere, which means nothing to damage or erode equipment. The moon is also quite likely devoid of numerous resources for a colony to be self-sustaining. Once established, how will the colony expand?
This is the account given by the New Scientist article:
The impetus came from a 2016 US funding bill telling NASA to study interstellar travel that could reach at least 10 per cent of the speed of light by 2069.
“It’s very nebulous,” says Anthony Freeman at JPL, who presented the mission concept at the 2017 American Geophysical Union conference in New Orleans, Louisiana, on 12 December.
In other words NASA was directed in a funding bill to study interstellar travel, with the launch date and performance mandated in the legislation! And NASA's response to this requirement imposed by lawmakers is to offer a "very nebulous" study.
Nothing to see here, just a beleaguered agency trying to address a ridiculous idea from a space nutter lawmaker.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
Am I? Again, how do you know at what phase are we at? In the 1940s, did you say "Train engines have been like this for the last fifty years, they'll always be like this"? In 1880, did you say "Taxi cabs have been like this for the last fifty years, they'll always be like this"?
Ezekiel 23:20
Isn't than an entirely different issue? Unless you want to convert the kinetic energy of the particles into electricity. The problem here is how (while in interstellar space) do you provide the energy for ignition which is substantial. For pulsed reaction, you need to provide it for every pulse. In continuous reaction, perhaps you need it once a while, but that's the very definition of high net energy gain anyway and probably not what Baron_Yam had in mind when he spoke of "a poorly confined fusion reaction".
Ezekiel 23:20
A PR start for somebody, perhaps, but not NASA. According to the New Scientist article the 2016 funding bill required them to perform such a study - even writing the performance and launch date into the legislation (because that works so well with other projects, right?)
So NASA produced the required study.
It was required by law to describe a 10% c mission to be launched in 2069.
Your dollars at work, as directed by legislators.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
So it'd have to be a robot mission.
Duh. Both the summary and TFA make it clear that this would be a probe, not a manned mission. It would be a flyby, passing through the Alpha Centauri solar system in minutes,
It depends on where you define the boundaries of the Star System. If you include the cocoon of debris enveloping the star [an Oort Cloud-like structure], and your ship can travel at c, we're talking about more than a year.
Ten percent of c? Years;
It depends on where you define the boundaries of the Star System
I was thinking of the time to pass through the Goldilocks zone, where liquid surface water can exist. It would zip through that in about an hour at 0.1c.
Depressing actually. Hell my children might see it get there. I have no faith that the singularity would go beyond the wealthy. The poor will be forced to die.
The proposed budget is ~ $100M. A manned mission would cost many many trillions.
That sounds more like an early concept exploration budget, you don't even get a Mars probe for $100M. If they can even find a workable interstellar probe concept I'm guessing it'll be closer to a trillion dollar project. And sending humans to Alpha fucking Centauri? Not if you dedicated the whole GDP of the world from now to 2069 to the task.
Live today, because you never know what tomorrow brings
Maybe we can make it two centuries in a row!
you don't even get a Mars probe for $100M.
The proposed mission to Alpha Centauri has a thousandfold smaller payload than the recent Mars missions.
Matthew McConaughey will be dead by then.
So now the U.S. want to win Freeciv? Without even putting people on Martian soil?
I wish best of luck for you.
Stupidity is an equal opportunity striker.
Fellow slashdotter Bill Dog
You don't seem to know what a ramscoop is or how it works which isn't surprising. A ramscoop uses magnetic fields to funnel interstellar hydrogen into a magnetic constriction point, where the pressure causes fusion to occur. The fusion reaction gives you thrust and therefore acceleration. It's a self-sustaining reaction, although you need to be at or above a certain velocity for the system to work -- so you also need stored hydrogen to get you up to speed. The magnetic fields themselves shield you from interstellar radiation (which just gets worse the faster you go). Theoretically you could reach 0.9999999999~ of C using a drive like this, acclerating forever. Some of the energy from the fusion reaction can be siphoned off to power other things. It's total Science Fiction/Fantasy though. But somehow getting your fuel source from interstellar space itself is an interesting idea.
Which seems senseless to me. Could such a probe even transmit anything back to Earth? Could such a probe collect interesting data in the first place? Could it serve any purpose other than crashing into a planet with a potentially hostile civilization?
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
It looks pretty dubious from the Wikipedia article. The energy required to divert the protons is going to get pretty large, and proton-proton fusion is difficult. The article suggests the carbon-nitrogen-oxygen-emit alpha-carbon cycle instead, but if you have to accelerate the protons to ship speed there's going to be a top speed.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
So far, we've looked at chemical rockets, nuclear rockets (a NERVA), throwing nukes behind the ship and smoothing the acceleration (Project Orion) , ion drives, solar sails, laser propulsion, and probably other things I have missed. So far, the practical, real technology we use to move mass to space is chemical rockets, and as you can see there's several other ways (not all suitable for launch from Earth).
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
You don't seem to know what a ramscoop is or how it works which isn't surprising.
It's not surprising, obviously, because nobody knows how it could possibly work.
A ramscoop uses magnetic fields to funnel interstellar hydrogen into a magnetic constriction point, where the pressure causes fusion to occur.
If only hydrogen were magnetic, right? And only fusion was this easy because otherwise we'd already have it. We can accelerate atoms but for some reasons fusion researchers are not inverting the process that you're proposing to ignite the fuel with. All the plans for scooping up interstellar hydrogen I've ever read only mentioned collecting it, handwaving the actual process very fervently.
Ezekiel 23:20
Doing (whatever they're planning) within a human lifetime wasn't part of the design specification.
If you have a mentality that cannot conceive of starting a project that neither you nor any children you choose to have (and can afford to be-sprog) will live to see the end of, and that, then clearly you are a person who is severely lacking in ambition. People like you will never be the progenitors (genetically, or psychologically) of the first human-derivative to see the Milky Way from the outside.
It also happens to fall into the range of events that are (1) not impossible, and (2) broadly within the range of technologies which we have reasonable control over. It's doable.
But I don't think that you're the person to lead the project. With some effort, you might be worthy to clean up the dead coffee cups. When they're using paper, not ceramic.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
"Goldilocks Zone"? Meh. We don't know for certain that it is possible to generate life in the sub-surface oceans of icy moons, but we do know that it is possible to combine chemical energy, liquid water and extended periods of time in such an environment. To discount such environments would be rash. It would make a mockery of any pretensions we have to being rational organisms.
At the costs of such an expedition, it would be ludicrous to not send something that can stay and report back to Earth. If that means more than doubling the mission length (to centuries, not multiple decades), then we should bite that bullet to get a first-version of a vonNeumann machine into another system. Once that has starting to build a space-bourn industry, then the human species is one large step closer to spreading through the rest of the universe. We may not be a wonderful species, but to the best of our knowledge, we're the only self-aware species in the universe. That's a big egg to have in one basket.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
So?
You don't do that. If you think it is important to send the genetics of humans to Alpha Centauri, then that's fine and good. Send the information. It's a small fraction of a gramme if you encode it as DNA molecules, probably less if you send it in some other encoding. You'll also need to send the information to build an incubation system, and to build the necessary infrastructure, but those are tasks that are under research already. Long before the "landing lasers" (opposite end of the "launching lasers" for Breakthrough Starshot) get ground-broken, you could have humans growing in artificial wombs over there.
Lather, rinse and repeat for the next star system out. A generation time of a century or two per colonisation is within the bounds of possibility. Each generation halves the probability of the human species dieing out. The odds of any human ever dieing in a different star system to the one in which they were born will remain small.
Star Trek it ain't, but it doesn't break the laws of physics.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Pretty hard to do on it's own. But since the proposal only requires the "launching lasers" to fire for a few months (until the probe is out in the Kuiper Belt) ... would you really only launch one probe then dismantle the lot?
Of course you woudn't - you'd launch a whole series of probes. Some at (say) 2.01 c, 1.99 c, 1.98 c, 1.97 c, ... (and not necessarily in that order) so that you havve multiple probes slowly separating in distance from Earth. The closer probes can then act as information relays for the more distant probes.
Perhaps you have to build your "launching lasers" on an asteroid - so at some times of the year it's line of fire would pass inconveniently close to the Sun (or Earth, or Jupiter ... or Planet 9 (of Brown & Batygin 2016) for several months. So, you leave it un-used? Or you launch the first batch of probes towards Procyon?
Hmmm, New Horizons? I don't see this being a big problem. Communications back to base being a bigger problem. And there wouldn't be a single probe anyway.
Very low probability. And also utterly irrelevant. Decades before the probe arrives in the target system, the "launching lasers" would have put a flickering brilliant light in the sky of the target. Further reading : first dozen or so chapters of "The Mote in God's Eye", 1991 by Larry Niven & Jerry Pournelle, Publisher: Pocket Books (March 1, 1991) Language: English ISBN-10: 0671741926.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
It obviously never occurred to you that I MIGHT have put that condition in because it's tough enough to get funding for a project that takes more than a single political administration, and downright impossible to get taxpayers to fund something they won't live to see a return on.
You lack the experience, wisdom and intelligence.
And you're a complete asshole, too.
You do realize that all they are doing is looking at Stephen Hawking's plan to send small probes to Alpha Centauri using solar sails given a huge boost by lasers.
It is a stupid idea but for different reasons. A small electronic payload will go by the system at 0.10c. If we're lucky we'll get a picture that we can call Great {Whatever Colour} Dot. Of course that's assuming our imaging technology works at 0.10c. Then we have no way sending images back but maybe someone can turn the sail into an antenna with some light bracing. Maybe the aliens there could shine a laser at the sail and slow it down for us and we could get a proper picture of their star system.