Hawking Backs $100 Million Interstellar Travel Project to Send 'Nano-Craft' To Nearest Star 381
At a press conference on Tuesday, Russian entrepreneur Yuri Milner, cosmologist Stephen Hawking and a group of scientists and philanthropists announced a $100 million research program to send robotic probes to nearby stars within a generation. The group believes that using a nano-spacecraft propelled by lasers, they will be able to reach Alpha Centauri in just over 20 years after launch. The nearest star system is 40 trillion km away, which using current technology would take about 30,000 years to reach there. The aforementioned group said that thanks to their research and development, they might be able to make a spacecraft that could cut down the duration to 30 years. Reuters reports: Tuesday's announcement, made with cosmologist Stephen Hawking, comes less than a year after the announcement of Breakthrough Listen. That decade-long, $100 million project, also backed by Milner, monitors radio signals for signs of intelligent life across the universe. Breakthrough Starshot involves deploying small light-propelled vehicles to carry equipment like cameras and communication equipment. Scientists hope the vehicles, known as nano-craft, will eventually fly at 20 percent of the speed of light, more than a thousand times faster than today's spacecraft. "The thing would look like the chip from your cell phone with this very thin gauzy light sail," said Pete Worden, the former director of NASA's Ames Research Center, who is leading the project. "It would be something like 10, 12 feet across."The Atlantic has just published an in-depth report on this, also explaining how this project came to being. You can also watch the live stream of the press conference.
Interesting, but.. (Score:5, Interesting)
Re: (Score:3)
However with a device that small, how do we get a signal back? It will not be able to generate a strong radio or light signal to send back.
Nevermind the fact that it's almost a 9 year round trip from sending a signal to receiving a reply when it arrives at its destination. Commands will have to be sent over 4 years before they're received and executed by the craft, so this thing will have to be preprogrammed for its entire mission before it even gets out of the solar system. I don't see how that can go wrong :)
Re:Interesting, but.. (Score:4, Interesting)
There wouldn't really be any commands to execute, all they are doing is basically shooting the probes towards Alpha Centauri.There wouldn't be anyway for them to manuever, it's not like they'd be able to slow down and get into orbit.
Re:Interesting, but.. (Score:4, Interesting)
The odds that a Slashdot reader will suggest quantum entanglement as a communications approach approaches 1 as a space-related thread grows ;)
There are people discussing the issue in the comments section on the Starshot page. For my two cents: given the described craft, which is to have a very flat sail and very high pointing accuracy.... it's really simple. You have a ~100GW class laser on Earth as a fundamental requirement of the proposal. Point it at your craft and fire. Even at those distances, the reflected light will be vastly more than such a tiny "chip" on the sail could ever possibly produce. As for how to modulate the signal, again, that's not tricky. Put a tiny piezoelectric vibrator in your chip. Even tiny vibrations will throw off the phase and particularly the pointing accuracy of the sail. If the vibrations aren't self-damping the you can use active damping to cancel them out.
When I first heard about this concept, my reaction was mostly "keep dreaming". But actually it's starting to sound more plausible (if they can work out the sail and nanoprobe, that is). For example, the lasers. 1TJ at 20% net system efficiency and industrial power rates of $0,05/kWh is only $70k. There's nothing unaffordable about that - even if your costs work out to be dramatically higher it would still be quite reasonable. But what about storing and then discharging such vast amounts of power? No need - use a chemical laser and store the feedstocks. Chemical lasers also give you the highest power outputs anyway because they discharge their heat in the exhaust, like rocket engines.
In particular, I'm looking at something like COIL. Discharge into water to recover the iodine as iodic acid, then recover elemental iodine from that through dehydraton followed by reaction with carbon monoxide. Elemental iodine is solid, so you can store it in a big pile if you wanted. The other side of the laser involves creating excited oxygen. COIL does it by reacting a mixture of hydrogen peroxide (produced by the anthraquinone process from hydrogen and water) and KOH with Cl2 (KOH and Cl2 produced from the resultant KCl by the chloralkali process). But alternative reactions might allow for lower capital cost storage, particularly in terms of avoiding Cl2 tankage. But if we assume that a traditional COIL approach is used, then what you need to drive the regenerative processes are carbon monoxide, hydrogen, and electricity. It just so happens that those are the three things you get from the partial oxidation of methane (aka natural gas) driving generator. Natural gas being the cheapest available fuel source in many areas.
Total stored feedstock mass for the laser should be on the order of several hundred tonnes. The most expensive chemical involved by far is elemental iodine, which is $30/kg. So no capital cost problem there. So it just comes down to the capital costs on the lasers and associated optics hardware.
Really, I'm not seeing any roadblocks in this regard.
Re: (Score:3)
No, it's more like 4 years or so, not 9. Why do you think a round-trip is necessary? The point of this thing is to go out there, collect data, and then beam it back here, just like the New Horizons probe to Pluto. It doesn't have to wait to receive commands to send data, it can send any time it wants to.
It should be obvious that with that much of a time-lag, there's no way to make this a remotely-operated vehicle, and it'll have to be completely autonomous.
Re: (Score:3)
Re: (Score:3)
The laser propulsion won't be shining at Alpha Centauri because it'll be far too diffuse to be of any use long before then. The acceleration will happen in our own solar system.
Re: Interesting, but.. (Score:5, Funny)
Re: (Score:2)
Re:Interesting, but.. (Score:4, Interesting)
Re: (Score:2)
..at least an not currently understood.
Sure, that's my whole point: At this point in time how can anyone have an accurate read on how much that could be developed by a focused, concerted effort?
Re: (Score:3)
Re:Interesting, but.. (Score:5, Informative)
No. Not being able to leverage quantum entanglement into actual FTL communications is a fundamental limit of how it works.
To state it simply. If two particles have their state entangled for a property then measuring that property on one causes the same measured property on the other to have the opposite value but which way around these are is essentially random and impossible to control. The best you can use this for is to securely duplicate a sequence of random values, (and in the case of sending one half of each pair to another site, assuming your implementation doesn't have any problems, know if someone had at all intercepted those particles).
This is why all current uses of the technology are used to send an encryption key which you then use to encrypt normal communications.
Re: (Score:3)
Re: (Score:2)
Re: (Score:3)
Round trip?
Re: (Score:2)
Assuming the propulsion laser is in solar system, the "sail" being a mirror that gets "modulated" and hence reflect back the laser light transmitting the information?
Re: (Score:3)
Re: (Score:3)
Re: (Score:2)
If you're not planning to make the craft slow down on the other side, why not continually accelerate the entire journey to make it as quick as possible (assuming the efficiency doesn't drop below some minimum threshold partway through)?
Re: (Score:3)
Something like that would hit the atmosphere of a planet like it was solid rock. There might be a light show, but it is unlikely that something that small, even at .5c would impart enough energy to cause a catastrophe on the ground.
Of course if there was an orbital habitat in the way... that could be different.
Re: (Score:3)
Re:Interesting, but.. (Score:5, Interesting)
If you have a continuous stream of launches, it would be simple to create a mesh network (for redundancy) that daisy-chains the length of the path to relay signals.
And by having a large cluster of detector devices you can have an arbitrarily large collective system for high resolution.
Re:Interesting, but.. (Score:5, Interesting)
Sure is. Which is why it requires creative solutions. And if they travel at 0.2C, and you launch every second then you have separation of about 60KM. That represents about 150 million units per light year to the target, or 600M to AC, spread over 20 years at, say $20 each so $600M per target per year, or one Shuttle launch per year
Re: (Score:2)
Re: (Score:3)
Seems like they really need to improve that feature first, otherwise it's utterly pointless.
Also, there was no mention of power supply. At the mass they're talking about, it won't be solar panels or nuclear batteries. Both are too heavy, and a solar panel would quickly become worthless and provide insufficient power. As to our regular batteries, I don't see them surviving that long, both because of insufficient st
Re: (Score:2, Informative)
Notice that it says they are starting a $100 million research program. I would assume the purpose of this research would be to answer those questions and figure out if its really possible to do this.
Re:Interesting, but.. (Score:4, Insightful)
Re: (Score:3)
That's no probe, it's a relativistic kill vehicle.
Re: (Score:3)
Nope. There's a rich Russian involved in there. That's where at least some of the money is coming from.
Apparently he got bored of buying tiny giraffes.
Obligatory Fermi (Score:5, Interesting)
So why hasn't "someone" done this already?
Re:Obligatory Fermi (Score:5, Insightful)
I'm aware of no human technology which would enable us to say with any certainty at all that there aren't 10,000,000 similar-sized alien probes in our solar system right now.
Re: (Score:2)
I'm aware of no human technology which would enable us to say with any certainty at all that there aren't 10,000,000 similar-sized alien probes in our solar system right now.
You don't think we'd be able to detect the powerful lasers that would be aimed at them ?
Re: (Score:3, Insightful)
Re:Obligatory Fermi (Score:5, Interesting)
You can't collimate a laser beam that perfectly. When I looked into that some time recently I believe for a visible red light laser you'd see significant dispersion after less than 10km. Yes, in a vacuum. Even if you could align the internals perfectly you'd still get a small amount of diffraction where the beam leaves the apparatus.
Over lightyears you're never going to maintain beam cohesion.
This also both answers the GP's question for the period of time the such a probe is being accelerated and why it wouldn't be accelerated the whole distance. Indeed given the travel time, even if accelerated to very close to the speed of light, you'd not be aiming the laser at the destination system (it would move some by the time the probe got there).
Re: (Score:2)
you'd not be aiming the laser at the destination system (it would move some by the time the probe got there).
That's a good point. So, basically you'd use the laser to give it a short boost, and then let it coast to the destination.
Re:Obligatory Fermi (Score:4, Interesting)
The write up on Ars Technica basically stated this... accelerate it to 20% speed of light within a very short span (half hour if I remember correctly), and send multiple devices for redundancy... Once the technology was built, there'd be no reason not to send thousands of them.
Re:Obligatory Fermi (Score:4, Insightful)
Re:Obligatory Fermi (Score:5, Funny)
You can't collimate a laser beam that perfectly. When I looked into that some time recently ...
... I remembered to be more careful with my remaining eye.
Re: (Score:2)
Why would you? The whole idea of a laser is that it stays cohesive. It isn't like you'd see the beam like using a laser in atmosphere.
You mean like using a laser in a dusty room. It takes effort to make the beam of a laser visible, contrary to how Hollywood represents it.
Re: (Score:2)
No, because the photons would be aimed at the probe, not at us.
Re: (Score:2)
No, because the photons would be aimed at the probe, not at us.
If the beam is wide enough, it would hit both. The laser we use for lunar ranging has a 6.5 km spot on the Moon's surface, and the Moon is very close.
Re: (Score:3)
Not if they're tightly focused enough. You only see a laser if A) it's pointed at you or B) it's going through a medium like dust or gas that parts of the beam reflect off towards you
Re: (Score:3)
Re: (Score:2)
Re: (Score:3)
I would say "no." First of all, the propulsion laser is only fired at it for a few minutes while it's still close to its launch point. Second, we wouldn't be in the laser's path if we were the destination since the laser light is traveling 5x faster than the probes (missing our location probably by several years, unless of course ours and theirs stellar movement is in exactly the same or exactly the opposite directions).
Re: (Score:2, Funny)
They were already swallowed by a small dog
Re: (Score:2)
. . . and that "Mutual of Andromeda's 'Wild Planet'", hosted by Mrln Prknz, is the Galaxy's number one reality show. And they don't even pay us for it, much less a year's supply of Rzz-a-roni, the Aldebaran Treat. . .
Re: (Score:3)
I'm aware of no human technology which would enable us to say with any certainty at all that there aren't 10,000,000 similar-sized alien probes in our solar system right now.
We would detect all the explosions they made when they hit the Oort cloud.
Better make two (Score:2)
>> fly at 20 percent of the speed of light
0.2C (Score:5, Informative)
Re: 0.2C (Score:2, Funny)
They'll probably use force fields and/or deflector shields.
Re: (Score:3)
They'll probably use force fields and/or deflector shields.
Oh come on, I'm being serious here, this is not a Star Trek fan forum we're commenting in.
Re: (Score:2)
No, silly. You just reverse the polarity and/or modulate the shield frequency.
Re: (Score:3)
Re: (Score:2, Interesting)
The fastest (relative to our sun) thing ever recorded in our solar system was only a few percent of the speed of light. We can treat all the rocks and dust in the solar system as basically standing still when talking about the relative speeds that this probe will take on.
Basically, you are talking out your ass, waving your hands about data that wouldn't apply if it were true, but isnt even true.
Re: (Score:2)
We can treat all the rocks and dust in the solar system as basically standing still
If you fly a probe through the asteroid belt, or any other kind of dust or rocks, it doesn't matter if they're standing still or moving.
Re:0.2C (Score:5, Funny)
More than a few probes have mysteriously been lost.
No mystery at all. They have been hit by nanoprobes launched from Alpha Centauri and were destroyed on impact.
Re: (Score:2)
Speaking of talking out your ass, exactly how many probes have mysteriously been lost?
Re: (Score:2)
I was thinking the same thing.
Also, related to that, once the craft gets to its destination, how does it slow down and send back information?
Re: (Score:3)
Also, related to that, once the craft gets to its destination, how does it slow down and send back information?
It doesn't. It makes a few pictures during a fly-by and sends those.
Re: (Score:2)
It doesn't. There's no way to slow it down, and given the size that's being talked about it wouldn't have enough power to have any hope of sending a detectable signal back (both because it wouldn't have enough stored energy and it also wouldn't have a big enough antenna to have any hope of aiming the signal back).
I suspect this whole thing would be more aimed at developing technologies and inspiring others to solve the various problems to sending a useful probe in the future.
Re: (Score:3)
Why don't you do the math your self?
Can't be so hard: e = m * v * v
Re: (Score:2)
Maybe the idea is that an advanced alien race will discover it, add on a whole bunch of mods and then send it back to Earth to report.
Re:0.2C (Score:5, Interesting)
Um, small or not, have they considered how the craft is going to be shielded against collisions at that speed? Even something as small as a grain of sand at 0.2C packs quite a wallop. Also, is radiation an issue at that velocity?
Collisions at 0.2C? Hell, even at 100 MPH (160Km/h) the probe will be pretty much destroyed.
The magic is that most of the universe is, well, empty. I didn't do the math for this particular case, but I remember one of NASA scientist that made such calculation of the probability of a collision of the voyager probe for the next millennium. It was several digit after the decimal point.
Re: (Score:3)
Even if we manage to pepper the Alpha Centauri system with these things, around a million or so, the odds of actually hitting a planet are? You would have better luck repeatedly winning the lottery every day for a year straight than hitting something over on the other side.
If these are space born, intelligent creatures on the other side, they will most likely respond with a serious, WTF?, rather than retaliate. That is if they are advanced and actually have quite an established presence(Thousands of Stati
Starwisp (Score:5, Interesting)
Something like this was proposed many years ago by Robert L Forward, called Starwisp. See https://en.wikipedia.org/wiki/... [wikipedia.org] for details.
The probe would be very light but extended, like a cobweb. Tiny processor/sensor nodes would exist where the wires touched. Some nodes and web filaments would undoubtedly be destroyed by dust collisions en route, but would be multiply redundant. On arrival, the probe would be tattered and torn but still functional.
Re: (Score:2)
Hopefully, nanotechnology will be developed to a useful level when and if they decide to launch. . . . of course, those of us who've read Charles Stross [wikipedia.org] wonder about the potential of a nanotechnology-enhanced Starwisp-type craft. . . .
Re: (Score:2)
Some nodes and web filaments would undoubtedly be destroyed by dust collisions en route, but would be multiply redundant. On arrival, the probe would be tattered and torn but still functional.
But would they? I wonder what the odds are?
There's a whole lot of empty between us and the nearest star. I wonder what the actual odds are of collision over that distance. Would be a neat problem for someone who knows this stuff ... which is not me.
Never gonna happen (Score:3)
I'm all for science, I work in a lab after all, but the technological tasks facing them won't be solved anytime soon.
Maybe 20 years from now, but not anytime soon.
Call me when they have a working, fully functional one.
Re: (Score:2)
Please notice that it says "a $100 million research program".
Unsurmountable obstacles (Score:5, Insightful)
Obstacles are way too high. Current calculation requires 60 Giga Watt laser beam. Largest nuclear plant in USA, Palo Verde, Arizona, has approx 1.25 Giga Watt power.
More: according to the plan, installations that generate power of 50 nuclear plants would need to be sent to space, for lasers are supposed to be above the atmosphere.
Finally, the power of 50 nuclear plants would be concentrated into the area more or less equal to handkerchief. I think that handkerchief will evaporate, maybe it will not. However there might be some interference at the interstellar probe. Technical difficulties are insurmountable so far.
Anyway, the last time I have checked approximately 50% of world's population did not have proper sewer, and approximately 15% do not have running water and electricity. Just a small fraction of interstellar travel project would bring these necessities to the fellow human beings. I would say, that we should build few nuclear power plants here on earth first.
I think that we will need 100 years to send a interstellar probe.
Re: (Score:3, Insightful)
approximately 50% of world's population did not have proper sewer, and approximately 15% do not have running water and electricity.
If you solve that, you'd get a bigger population, followed by the same problems on a larger scale.
Re:Unsurmountable obstacles (Score:4, Informative)
Perhaps we will get bigger population. However, history shows, that once electricity, television and contraceptives are introduced, population growth slows down significantly. Once population becomes richer population growth turns negative.
Re: (Score:2)
history shows, that once electricity, television and contraceptives are introduced, population growth slows down significantly
Temporarily, yes. But after a few generations, it'll pick back up. Welcome to Evolution 101.
Re: (Score:2)
There will be always a way to slow down growth. Here are the few trends:
1. Fantasy football (or online games) will be compulsory. To make sure those who proudly do not have cable TV, are using their time on the internets.
2. Everyone will need to get a PhD and compulsory post-doctoral studies just to get a job to maintain and service fast food robot servers. Many of the people get postdoc education at around 35 years.
3. Having a child will be so expensive (both in terms of time and money), that many will cho
Re: (Score:2)
Re: (Score:3)
Perhaps we will get bigger population. However, history shows, that once electricity, television and contraceptives are introduced, population growth slows down significantly. Once population becomes richer population growth turns negative.
Yeah....let's see how that argument hold when we'll find a cure to, let's say, double the life expectancy (and double the fertility time) of a human being.
Re: (Score:2)
Re: (Score:2)
Anyway, the last time I have checked approximately 50% of world's population did not have proper sewer, and approximately 15% do not have running water and electricity. Just a small fraction of interstellar travel project would bring these necessities to the fellow human beings.
"15%" of the world's population doesn't have running water? The number is closer to 50%. If you were *actually* concerned about water issues in the developing world, I suspect you would know that already. (And no... a "small fraction" of a $100 million research budget isn't going to bring indoor plumbing to 3.5 billion people).
Re:Never gonna happen (Score:5, Funny)
Call me when they have a working, fully functional one.
Why, so we can get another awesome opinion?
Re: (Score:3)
War comes first (Score:3, Insightful)
At $100 million, that's roughly the cost of 40 airstrikes against ISIS. It's too bad we're such a trigger-happy country, we aren't willing to let our thumbs rest [quora.com]for two weeks [ibtimes.com] and use the money we saved to launch a scientific mission instead.
I can already see how it ends (Score:4, Funny)
For decades, the tiny ships will tore across the empty wastes of space to finally dive on to the first planet they come across, where due to a terrible miscalculation of scale the entire space fleet will be accidentally swallowed by a small dog.
Re: (Score:2)
Numbers? (Score:3)
A visible light laser can't practically be focused to meter scales over more than about ~10^7M considering diffraction and reasonable (eg 10s of M) sized mirrors. At 0.1C, that gives you an acceleration time of ~1 second. So the sail material is hit by ~10% of its mass energy in 1 second. No way it could possibly survive, even if the laser could be constructed.
Considering that a 30M telescope is a ~$1B project, requiring a much larger telescope is not consistent with a $100M project.
This is why we need experimental physicists as well as theorists.....
Re:Numbers? (Score:5, Funny)
Accelerator physicist - which really means engineer......
but I play Kerbal a lot so I'm an expert in space stuff ;-)
Re: (Score:3)
The mirror has to be very good. My numbers were roughly based on diffraction limit. If you have a worse quality mirror it needs to be larger.
I'm not saying that its physically impossible, but if you put in numbers for a reasonable mirror size, and power dissipation on the sail, it quickly becomes clear that it doesn't come close to working.
Going to soft X-rays helps because diffraction limit is much smaller. (hard x-rays and higher don't work, the sail needs to be too think to absorb them). Still the nu
AC has no hostile beings? (Score:3)
Re: (Score:2)
Let's hope they can keep the lights on...
And the beam focused to a point the size of a SIM card at a distance of 40,000,000,000,000,000 meters.
Re: (Score:3)
Of course building a gigantic laser in orbit around the Earth, or on the Moon, or anywhere it could possibly be pointed back at the Ea
actually some sort of hovercraft (Score:3)
Re: (Score:2)
Solar sails get pretty useless even before you get halfway to the heliopause. For an interstellar journey, they're completely useless *unless* you point a laser at them.
Re: (Score:2)
Unless your SIM card is two meters wide, I think you missed the part where they're using a sail. Not that it matters at that distance.
Re: (Score:2)
I suppose by "ground" they meant "stationary" as in "not on the spacecraft"...
Re: (Score:2)
Oh great, now the damn things will need to run Java.
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
And between you and Hawking, who is the Journal of Quantum Physics going to believe?
Re:Quantum entanglement (Score:4, Insightful)
I mean, how hard can it be?
It can be, and is, impossible.