NASA Selects Bold Proposal To 'Swarm' Proxima Centauri With Tiny Probes (universetoday.com) 113
In order to reach places like Alpha Centauri this century, we'll need to utilize gram-scale spacecraft that rely on directed-energy propulsion. To that end, NASA has selected the Swarming Proxima Centauri project for Phase I development as part of this year's NASA Innovative Advanced Concepts (NIAC) program. According to Universe Today, Swarming Proxima Centauri is "a collaborative effort between Space Initiatives Inc. and the Initiative for Interstellar Studies (i4is) led by Space Initiative's chief scientist Marshall Eubanks." From the report: According to Eubanks, traveling through interstellar space is a question of distance, energy, and speed. At a distance of 4.25 light-years (40 trillion km; 25 trillion mi) from the Solar System, even Proxima Centauri is unfathomably far away. To put it in perspective, the record for the farthest distance ever traveled by a spacecraft goes to the Voyager 1 space probe, which is currently more than 24 billion km (15 billion mi) from Earth. Using conventional methods, the probe accomplished a maximum speed of 61,500 km/h (38,215 mph) and has been traveling for more than 46 years straight.
In short, traveling at anything less than relativistic speed (a fraction of the speed of light) will make interstellar transits incredibly long and entirely impractical. Given the energy requirements this calls for, anything other than small spacecraft with a maximum mass of a few grams is feasible. [...] In contrast, concepts like Breakthrough Starshot and the Proxima Swarm consist of "inverting the rocket" -- i.e., instead of throwing stuff out, stuff is thrown at the spacecraft. Instead of heavy propellant, which constitutes the majority of conventional rockets, the energy source for a lightsail is photons (which have no mass and move at the speed of light). But as Eubanks indicated, this does not overcome the issue of energy, making it even more important that the spacecraft be as small as possible. "Bouncing photons off of a laser sail thus solves the speed-of-stuff problem," he said. "But the trouble is, there is not much momentum in a photon, so we need a lot of them. And given the power we are likely to have available, even a couple of decades from now, the thrust will be weak, so the mass of the probes needs to be very small -- grams, not tons."
Their proposal calls for a 100-gigawatt (GW) laser beamer boosting thousands of gram-scale space probes with laser sails to relativistic speed (~10-20% of light). They also proposed a series of terrestrial light buckets measuring a square kilometer (0.386 mi2) in diameter to catch the light signals from the probes once they are well on their way to reaching Proxima Centauri (and communications become more difficult). By their estimates, this mission concept could be ready for development around midcentury and could reach Proxima Centauri and its Earth-like exoplanet (Proxima b) by the third quarter of this century (2075 or after). [...] Eubanks and his colleagues hope that the development of a coherent swarm of robotic probes will have applications closer to home. Swarm robotics is a hot field of research today and is being investigated as a possible means of exploring Europa's interior ocean, digging underground cities on Mars, assembling large structures in space, and providing extreme weather tracking from Earth's orbit. Beyond space exploration and Earth observation, swarm robotics also has applications in medicine, additive manufacturing, environmental studies, global positioning and navigation, search and rescue, and more.
In short, traveling at anything less than relativistic speed (a fraction of the speed of light) will make interstellar transits incredibly long and entirely impractical. Given the energy requirements this calls for, anything other than small spacecraft with a maximum mass of a few grams is feasible. [...] In contrast, concepts like Breakthrough Starshot and the Proxima Swarm consist of "inverting the rocket" -- i.e., instead of throwing stuff out, stuff is thrown at the spacecraft. Instead of heavy propellant, which constitutes the majority of conventional rockets, the energy source for a lightsail is photons (which have no mass and move at the speed of light). But as Eubanks indicated, this does not overcome the issue of energy, making it even more important that the spacecraft be as small as possible. "Bouncing photons off of a laser sail thus solves the speed-of-stuff problem," he said. "But the trouble is, there is not much momentum in a photon, so we need a lot of them. And given the power we are likely to have available, even a couple of decades from now, the thrust will be weak, so the mass of the probes needs to be very small -- grams, not tons."
Their proposal calls for a 100-gigawatt (GW) laser beamer boosting thousands of gram-scale space probes with laser sails to relativistic speed (~10-20% of light). They also proposed a series of terrestrial light buckets measuring a square kilometer (0.386 mi2) in diameter to catch the light signals from the probes once they are well on their way to reaching Proxima Centauri (and communications become more difficult). By their estimates, this mission concept could be ready for development around midcentury and could reach Proxima Centauri and its Earth-like exoplanet (Proxima b) by the third quarter of this century (2075 or after). [...] Eubanks and his colleagues hope that the development of a coherent swarm of robotic probes will have applications closer to home. Swarm robotics is a hot field of research today and is being investigated as a possible means of exploring Europa's interior ocean, digging underground cities on Mars, assembling large structures in space, and providing extreme weather tracking from Earth's orbit. Beyond space exploration and Earth observation, swarm robotics also has applications in medicine, additive manufacturing, environmental studies, global positioning and navigation, search and rescue, and more.
If photons have no mass... (Score:1)
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No (Score:5, Interesting)
Don't present science fiction this way. You cannot aim sufficient energy over distances like that and you can't slow these gram-weight "robots" down with this propulsion system. They're either going to go too slow or just become tiny meteorites once they get there. It won't matter though because communication from a tiny probe that far away right next to a star is going to be impossible. It's a slush fund project.
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Re:No (Score:5, Funny)
I have a firmer grip on funding shenanigans than you, apparently.
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So if the bridge that I have to sell to you is cheap enough upfront, you'll buy?
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People actually familiar with NASA know the gaming is overwhelmingly at the high-funding end of the scale. NIAC is extremely valuable.
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What kind of misanthropic POS believes people pursue careers in science just to con institutions out of pocket change?
People who don't like the results science produces.
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Indeed. And perhaps moral revenge for feeling inferior to those who do important work.
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If I can charge tolls from the travelers over the bridge: certainly.
Re: No (Score:2)
And if I tell you my bridge design is made out of forcefields and holograms, which might exist by 2075, will you still give me a $100k today to get to work on it? $10k? A dollar? The time of day?
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Well, I said: if I can collect road tolls.
I doubt that is possible on a hologram.
But we could try. With you as business partner: what could go wrong?
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Some people apparently don't know what "I have a bridge to sell you" means. Hint: It's a reference to a conman. [wikipedia.org] You do not get the bridge. It means I think you're gullible, because you are willing to spend money on empty promises. The price doesn't matter.
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Do you understand what the word "research" means? It means "we don't know what we're doing, or if it'll work". And the point of "Phase 1" studies is to work out what would be required, and if those technologies could be made to work (or if the idea would need redesign to be more achievable).
If you don't like it, feel free to spend the rest of your life working up the greas
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As a human and a tax payer, I prefer "my money" to be spent on space research, instead on a cheaper bomb to kill the kids on a wedding in a desert.
Regarding research: there are different phases, inception, conception, can it be done etc.
If you do not want to put your money into research up to you.
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So in return for $100k I get progress on forcefields and holograms?
Assuming the proposal for the hologram and force field progress is possible and I had the science funding it would go into the pile of things to look into further.
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If the price is low enough, the scrap value of the bridge and the real estate it's one may well be worth it.
This project sounds like it's some basic research for a future "real" project that needs some spiffy, publicity-garnering tackle. If those 175k lead to us being able to do some real interstellar research somewhere in the next half century, that's money well spent, but if you try to just tell the people "We're gonna spend 175k on researching something you'll never get to see anything of", it's a pretty
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Humor me, I have no other hobbies.
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Re:No (Score:5, Funny)
They're either going to go too slow or just become tiny meteorites once they get there.
But what could be friendlier than (basically) firing bird-shot using a giant death-ray at an alien system. There's no way any inhabitants could possibly mistake that as anything bad ... :-)
[*cough* Klendathu *cough*]
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A 10GW laser is only a death ray when you look straight into it from a few giga meters distance with your remaining eye.
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A 10GW laser is only a death ray when you look straight into it from a few giga meters distance with your remaining eye.
TFS notes it's a 100 GW laser, not 10 (in case your's isn't a typo) ...
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Oh, I indeed saw 10 and not 100, thanx.
Regarding the deathray point. I guess such a thing needs to be in orbit, to be able to be pointed the same way for weeks.
Depending on wavelength such a laser would indeed be WMD, if the laser can penetrate the atmosphere.
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you can't slow these gram-weight "robots" down with this propulsion system.
A fly-by mission can collect a lot of data.
The Pluto mission was a fly-by. So was Voyager.
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A fly-by mission can collect a lot of data.
No argument there, but if the probe can't send that data back to Earth what's the point in the mission?
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The probes will sent data back.
Probes will drop out of the stream every few light seconds and form a relay for data transmissions home.
Re: No (Score:2)
You never took a telecom class in college, did you?
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I never was on a college.
I jumped from High School to University.
Well, actually I'm on a college right now. But that is English Teacher TESOL program and has nothing to do with CS. I try to switch to an Solar Energy/CS PhD program, but my native language skills are a problem ATM.
I doubt the probe swarm has any contract/SIM card with any majour telecom providers, though.
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Probes will drop out of the stream every few light seconds .
Ah yes, these gram sized probes with their motors of some kind, and their science collection instruments, and their insterstellar class transmitters and their power sources to run all that shit. I'm sure that's exactly what they will do.
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No, the ones that drop out "feather" (sailing term) their beam-collecting device to reduce the propulsion they receive, so that they drop back with respect to the bulk of the swarm. Since the mission construction is intended for a single flyby phase (with an extended playback phase - see the several years it took to get New Horizons data from spacecraft to Earth, both times), you can also launch the main swarm (phased in velocity to arrive en ma
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4.2 lightyear / 5.3712 billion km (pluto distance) = 7 397.64285
Their is a power source from the beamed light.
If we can get the probe to transmit from Pluto to Earth then it can transmit to the next probe that is further back in distance.
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Yes their is going to be a lot of research needed to get this to happen but this is what the funding is for.
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In addition to the problem of sending back data, at 10% lightspeed it's more a shot-by than a fly-by.
Well, on the other hand that would mean very few data to send back, which may help...
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Reading the proposal, that's why they are sending a swarm. The idea is that they all sync clocks using laser pulses from Earth, and then all flash back simultaneously. With enough of them it's hoped that the signal can be received, but you still need massive reflectors on Earth to capture the light.
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(I happen to know one of the people involved.)
You cannot aim sufficient energy over distances like that
They were originally intended to be powered by betavoltaic batteries (solar cell sandwich with a charged particle emitter for the peanut butter - like the "radioactive diamond" batteries but with Strontium 90 for the radiation source). But another dude computed what local interstellar hydrogen looked like when treated as a proton/electron beam at 20% of light speed and concluded no other radiation source
Oh, yes... (Score:2)
You cannot aim sufficient energy over distances like that
[description of betavoltaic battery run off "interstellar wind" of high-speed travel]
Oh, yes...
You CAN aim the propulsion energy well enough for long enough to get them up to 20%ish of lightspeed. After that the energy is stored in their momentum relative to that of the interstellar gas. You don't have to keep powering them from home and there's far more than you need to power them for the rest of the mission.
Re: Oh, yes... (Score:2)
But you can't build a 100GW laser. Even if the Russian oligarchs who funded an earlier iteration of this study at UCSB really really want a 100GW laser.
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But you can't build a 100GW laser. Even if the Russian oligarchs who funded an earlier iteration of this study at UCSB really really want a 100GW laser.
It'll probably be a space laser, so guessing it will be built by not Russians [nymag.com] ... :-)
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AXIS would disagree.
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'you can't slow these gram-weight "robots" down with this propulsion system'
If you're going to cry "science fiction" then you should include that there is already at least one solution in the literature. Robert L. Forward included a solar sail that could decelerate in _Rocheworld_ forty years ago.
Re:No (Score:4, Informative)
Well maybe you are the biggest fish in financing, however this is a well known and discussed for some time concept of sending micro space-probes called Breakthrough Starshot [wikipedia.org] - supported by e.g. Seven Hawking, but who is he to compare with your vast scientific expertise.
Yes, the communication is a problem - one of many challenges, which this project is facing, and which is being worked out.
Despite vast financing from Yuri Milner every once a while NASA add some funding to one of the components of this project via NIAC mostly. If you followed NIAC (I am sorry, for sure you must followed, so just to remind), it is a program to support innovative concepts and some of them a pretty wild, yet always very interesting.
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The idea, I think, is to use 'spare change' to fund some crazy shit on the off chance it'll work out somehow. The problem is that this proposal is obviously crap. No, a 1g probe cannot carry a useful sensor package, cannot carry a useful processor, and cannot carry a useful signal generator. Even if you ignore the signal issue, there's still nothing a 1g hardware package could do that we couldn't do - and do better - with a space-based telescope much, much closer to Earth.
At least with the reactionless
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How did the voyagers and new horizons slow down after visting the planets?
As for communicating you send a relay of probes to pick up the signal and pass it on.
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This is why it is such a small amount. It is a maybee this will work so lets have a look at it.
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Actually, for a different iteration of this mission design, that's not so much of a problem. With "sails" designed for initial acceleration by maser radiation, but also capable of reflecting sunlight, to get to Proxima Centauri, you aim the spacecraft at Alpha (or Beta, same difference) Centauri, decelerating from the initial maser boost for a lot of the route, then do a "sundive + slingshot" around Alpha (or Beta) to come out wit
What about Halley's Comet? (Score:3)
How about something more practical today like a flotilla of probes to orbit and land on Halley's Comet before the ice starts evaporating?
Physics (Score:5, Insightful)
They also proposed a series of terrestrial light buckets measuring a square kilometer (0.386 mi2) in diameter
Diameters are not measured in square kilometres.
"Bouncing photons off of a laser sail thus solves the speed-of-stuff problem,"
Stuff doesn't have a problem with speed. This is not a recognized problem.
"But the trouble is, there is not much momentum in a photon, so we need a lot of them.
There is as much momentum in a photon as you want to give it. The photons you plan to use may not have much momentum but that's not a general property of all photons and there is no upper limit to a photon's momentum.
The claim that it is more energy efficient to send a swarm of gram-sized probes instead of fewer, larger probes also makes no sense: the total mass determines the energy requirements not how it is shared between the probes. There is also zero discussion of the aims of doing this. Are we really going to learn much at all from what will probably be little more than a swarm of randomly oriented webcams passing through a solar system at 20% of the speed of light? There will be zero chance to tell them to point at any planets given the signal delay.
Re:Physics (Score:4, Funny)
Picky picky picky. Next I suppose you're gonna pick apart the Millennium Falcon's 12-parsec Kessel Run record...
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Also how would a gram probe beam back any information back to earth, because of the total power available to these things, and because they would be right between us and the blinding light from the star.
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The probes will collect energy from the star.
They will use a directional RF beam in a frequency not generated by stars.
Stars emit synchrotron radiation [wikipedia.org] in a wide RF spectrum. The probes will emit in a very narrow spectrum.
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there is no upper limit to a photon's momentum.
Maybe. Some physicists believe there is an upper limit when the wavelength reaches a Planck length.
L = 1.6e-35 meter.
F = 3e8 / 1.6e-35 = 1.8e43 Hz.
E = hF = (6.6e-34) * (1.8e43) = 12 billion joules
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If you're gonna be pedantic, do it right.
There is as much momentum in a photon as you want to give it.
There's as much momentum in a [specifically photons aimed at this device] as you can give it, not as much as you want to give it.
And guess what? We can't actually give them very much.
Are we really going to learn much at all from what will probably be little more than a swarm of randomly oriented webcams passing through a solar system at 20% of the speed of light?There will be zero chance to tell them to po
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TFA doesn't say, but maybe they intend to brake by turning their sails to face the target star. It will lengthen the journey, but might allow them more time to capture data.
I just hope there is nobody living there, or they might be alarmed by high speed artificial objects aimed at them.
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Nothing like blasting away with a relativistic shotgun to show you mean business.
Plugging the numbers, 10g at 0.3c has the energy of about 10kT of TNT. It wouldn't be like a nuclear bomb going off if it hit something, it would be a nuclear bomb going off, since IIUC, 0.3c is fast enough that it's going to cause fusion with whatever it smacks into.
On the other hand, I guess it's very very very unlikely to hit
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Surprisingly: Beta Centaury has an Earth like planet.
Could one make to believe on gods, but probably just a stupid incredible unlikely coincident.
But it is as it is: the closest star system to Earth, has an Earth like planet. Believe it or not.
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Beta Centauri is only related to Alpha Centauri by being in the same constellation and part of the southern cross, from our view point and is an order of magnitude (390 LY) further away. Can't find anything about a planet and considering the type of star the main one is, life is unlikely.
Perhaps you meant Proxima Centauri, the closest star currently which does have an Earth sized planet at the right distance to possibly have liquid water. Problem is the planet is tidally locked orbiting a flare star, which
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Yes, it is a weird way of naming stars, by constellation with the Greek letter up front and letters to signify members of one system.
Doing pedantic right, but perhaps too much (Score:2)
There's as much momentum in a [specifically photons aimed at this device]
That's not what they wrote though they said that there is not much momentum in _a_ photon making it sound as if they were talking about all photons. Were they referring to just their photons then "the photons" would have been the correct term. Use of the indefinite article changes the meaning to include any photon in general. Perhaps I was being too pedantic but I was definitely doing pedantic right! ;-)
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Ah fair point! I cede today's pedant-off reluctantly up you.
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In nitpicking mode today?
Asking for a friend.
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My god the quality of tech reporting has truly reached Gen Z levels.
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One complex system is more vulnerable to failure than a bunch of spatially distributed/redundant systems.
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Machine vision is already good enough.
Good enough for what? Given that there will be zero time to receive a picture and direct a probe to point and zoom - at that point the round trip to get a signal and send directions will be over 8 years - the cameras will effectively be randomly oriented since we will have no idea what to point them at. Given that you'll presumably be taking wide-angle pictures to try and capture everything you can and it is hard to see how those will contain much detail.
Relativistic anything is a potential weapon (Score:2, Informative)
In the unlikely event that there's any intelligent life nearby, we should err on the side of caution and not go firing relativistic anything until we have some ability to divert it, should it turn out that the swarm is approaching something we didn't intend to destroy.
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It would be going fast enough that it probably wouldn't have time to burn up and may hit the atmosphere hard enough that the atoms in its way would under go fusion
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An object with a mass of a gram, perhaps half a cubic centimeter in volume, is much different then a cosmic ray which usually consist of a few protons/neutrons enlarged by relativistic speeds.
I don't know enough to say what would happen, so perhaps you're right and it would burn up in the 0.003 seconds it takes to traverse the lower 100 miles of atmosphere. We're talking about an object going perhaps 37,000 mile per second, depending if it slowed down much on the trip.
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Its so much energy it couldn’t possibly survive the journey to the
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Wouldn't it just turn into a ball of plasma still moving at the same speed? Seems to me that the atoms in front of it would also get severely compressed as no time to get forced to the side, and would heat up or even start fusing.
You may have a point about the trip, a one gram object could easily have its trajectory changed, Voyageurs trajectory was changed just by heat.
Personally, I have a hard time with a one gram object having a good enough power supply, computer, means of changing its trajectory, useful
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I have a hard time with a one gram object having a good enough power supply, computer, means of changing its trajectory, useful sensors and the means to communicate across light years.
Yea, it’s a bit beyond what we can do. I’m assuming it would have some kind of ultra light solar sail to somehow do in flight corrections but that only adds to the cross sectional area. I’m guessing anything going at .1C needs shields in the form of an insanely narrow cross section design and the first 20% something insanely dense and t
whut? (Score:1)
"Given the energy requirements this calls for, anything other than small spacecraft with a maximum mass of a few grams is feasible"
What exactl does this doodle mean? It's not a sentence. It suggess only large spacecraft [are] feasible. The rest of the article implies the opposite.
Can anyone who understands this please translate?
Bobiverse (Score:1)
This is the hard way (Score:2)
10% c not 20% (Score:2)
Electrons travel at ~ .1c
I'm highly doubtful that we can accelerate whole molecules faster than that.
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Electrons travel at ~ .1c
I'm highly doubtful that we can accelerate whole molecules faster than that.
Electrons can go a lot faster than that. If you plug 100GeV from the Large Electron-Positron Collider into this calculator [omnicalculator.com] you get more than 99.9% of the speed of light. Likewise for lead ions at >500TeV [stackexchange.com] in the Large Hadron Collider.
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You totally missed the point!
How fast can a *MOLECULE* be accelerated?
Try water, for instance.
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Yes, I did miss the point you were making. From this article [i4is.org] it looks like 10 minutes of acceleration to get to 0.2c, which I think is an acceleration of 17000g. I have no idea if this is feasible. It should be possible to reach high speeds with gentler acceleration, though. For example, 120 days at 1g should achieve the same speed as 10min at 17000g.
How do you stop? (Score:2)
Maybe you can really get this stuff moving fast toward the midpoint, but how do you stop at the destination?
With onboard propulsion you would just flip the craft at the halfway mark, and fire the rocket (or whatever) in the other direction, but if this is using the momentum from Earth photons to go, I'm drawing a blank on how to decelerate. Do I have to .. *shudder* .. RTFA?
Niven - the mote in gods eye (Score:3)
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Green. Their yellow star was in front of a red giant and when they fired their green laser it went from being a yellow mote in a red eye to a green one that outshone the giant.
There's a sequel book, BTW.
100 Gigawatts? (Score:2)
Nope (Score:2)
Aina nothin' we send gonna reach no 'nother star in a century. Nope.
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SF? (Score:1)
Sounds like the premise behind Larry Niven's 1974 novel "The Mote in God's Eye."
2075 (Score:2)
Remarkable (and depressing) to consider that they're planning ahead to a time when I will likely be dead.
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I'll be surprised if the project stays funded, since even without delays everyone funding it will die before there's any payoff.
Also, I wonder what it will cost to fund the laser for half a century.
Read the paper. (Score:2)
I'll be surprised if the project stays funded, since even without delays everyone funding it will die before there's any payoff.
Flight time is about 20 years. (Proxima is about 4 light years away and the swarm is averaging about 1/5th lightspeed.) I suspect even some of us boomers can hang in here that long - even if life-extension treatments don't become available.
Also, I wonder what it will cost to fund the laser for half a century.
The launch and acceleration of the whole swarm is over in about a year.
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Flight time is about 20 years. (Proxima is about 4 light years away and the swarm is averaging about 1/5th lightspeed.) I suspect even some of us boomers can hang in here that long - even if life-extension treatments don't become available.
Oops. Maybe not. They're talking about 75 years before getting around to a launch.