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Starlight interstellar probe
- noduerme 4y agoIt's a great proposal, it's been around for some time. Who's going to implement it? I could see Musk throwing some spare change at it, but 20+ years is a long time to wait for a news cycle.
- SturgeonsLaw 4y agoThe privatisation of spaceflight is opening up a new era, and will lead to an increasing pace of innovation in the space (get it), but this is why there should always be a place for publicly funded space projects, à la NASA. We all progress when there are entities out there who can take on the big, long term projects that don't have an ROI measured in quarters.
- onethought 4y agoBut NASA floundered about without even a launch capability for over a decade until private sector not measuring ROI in quarters with a long term vision to reach mars came along. Literally your example is the inverse of what has occurred. SpaceX sparked this current era, NASA in fact piggybacked on it, now that the cost of launch is lower NASAs fiddling around the edges is somewhat useful. But everyone is waiting around for SpaceX to solve the hard problems (cheap tonnage to orbit, and multi-planetary landing systems)… because NASA didn’t. (Admittedly NASA funds are funding a lot of SpaceX)
- ceejayoz 4y ago> But everyone is waiting around for SpaceX to solve the hard problems (cheap tonnage to orbit, and multi-planetary landing systems)… because NASA didn’t. (Admittedly NASA funds are funding a lot of SpaceX) I don't think you're giving NASA enough credit here. The Commercial Crew and Cargo programs were innovative bets that paid off in spades. I hope they do more like it. I tend to blame the floundering period on Congress.
- fallingknife 4y agoThe main reason for the rocket failure is because it wasn't a rocket program. It was a jobs program. NASA actually does extremely well with its science missions, because they are actually science missions, and not jobs programs.
- sph 4y agoCan we stop calling for notoriously fickle Elon Musk to lead space innovation? SpaceX is great, but it's starting to feel more and more like a cult of personality, and not that great of a personality either. Any time there's a post about space on social media (HN included), there's always some starry eyed commenters saying "Musk could maybe do it". It's not like he needs more publicity.
- fallingknife 4y agoNo one alive on Earth today has both the level of ability to execute and the available funds to match Elon Musk.
- skykooler 4y agoI think it's mainly because there are basically only two individuals who own a space company and have the money to do a project like this. And Bezos has not been very successful at getting things done, space-wise.
- euroderf 4y agoWill the aliens that detect & intercept the probe wonder how something as simple as the nematode built & launched the probe.
- adipginting 4y agoThat is a positive assesment. On the other hand, imagine if the aliens think that the senders of these probes were deliberately sending pathogens to the aliens' worlds. This is a statement of war.
- rapind 4y agoThey'll just assume that the idiot species sending out statements of war have already been taken care of (probably by themselves).
- rrwo 4y agoNematodes manipulated evolution to produce organisms that would send them to other solar systems.
- dclowd9901 4y agoIf they had our level of intelligence, probably.
- usrusr 4y agoAlpha Centauri aliens who'd be able to detect and intercept that probe would have their Twitter flooded with funny memes made from our hn discussions of the mission long before the actual probe arrives. Actual arrival wouldn't even make it into their news.
- jcfrei 4y agoIs there any way for these probes to communicate with earth during their journey?
- dghughes 4y agoThese proposed devices use laser or solar on a giant multi kilometre area material. I wonder if the shape of the material could also be a dish used to transmit a signal back to earth.
- ncmncm 4y agoThere has been no hint of any answer to this question. Did they think no one would notice?
- 0xf00ff00f 4y agoFrom their report: > We have run link margin calculations including Zodi, CIB, galaxy and optical emission for such a wafer scale system run in a hibernate/burst mode using the DE-STAR array as both the transmitter of power to propel and communicate with the spacecraft as well as to receive the very weak signal from the spacecraft and conclude it is feasible to receive data (albeit at low rate) at light year distances. Source: https://www.nasa.gov/sites/default/files/atoms/files/roadmap_to_interstellar_flight_tagged.pdf https://www.nasa.gov/sites/default/files/atoms/files/roadmap...
- sliken 4y agoThis isn't new, there's been many discussions. But generally you spend billions making lasers, on the ground, in orbit, and on the moon has been suggested. You make the space craft with a sail a few atom thick surface tuned for the frequency of the laser to minimize weight and maximize thrust. However even 1% of the speed of light means it's going to be too far to accelerate significantly on the order of 10 minutes to 10 hours. Sure we could put laser arrays on the outer planets, but that's not particularly feasible today. So what do you do with your $billions of lasers once post launch ... of course launch more. Especially since you are likely to lose some due to radiation and space dust. Launch once an hour and hopefully your communication system can handle hops of 4 or more ships, which would be 4 hours * 0.01C = 0.04 light hours or about 1/3rd the way to mars. With some fancy encoding that doesn't seem so hard. People get across the earth on a few watts with signals 20db below the noise floor, no line of site, and a message energy sapping atmosphere and bounces off not particularly reflective soil. For some idea on the difficulty, with 1970s tech (45 years ago), voyager 1 has a 22 watt transmitter and is still communicating from well past pluto.
- idiocrat 4y agoPerhaps it will quickly become mushy minced goo, a mix of protein parts -- after so many years of radiation.
- mofosyne 4y agoSounds like an important fact to figure out if true or not. That would inform if our exploration should be purely AI based or if we can transport humans across the stars.
- Pxtl 4y agoRealistically our existence will be purely AI based by the time we figure out how to transport things across the stars, if ever.
- DrBazza 4y agoI thought there was another name for it, but it seems that the Wait Calculation, is applicable right now, i.e. if we send something now, we might as well wait for X years and send something that's faster and will over take whatever we send now. https://en.wikipedia.org/wiki/Interstellar_travel#Wait_calculation https://en.wikipedia.org/wiki/Interstellar_travel#Wait_calcu...
- tyho 4y agoThe wait calculation doesn't really apply to this project. The whole basis of it is that new technology can't speed up probes you have already launched. This isn't true for these probes as improvements in technology can be used to increase the speed of the probes that have already been launched. It also assumes that the bulk of the investment is in the hardware that's launched. With this project, the expensive stuff stays on the ground, the probes are cheap.
- denton-scratch 4y agoI'm not ssure it's ethical to deliberately send organisms to a distant planet. A novel organism can destroy all other life on a planet; it happened here. https://en.wikipedia.org/wiki/Cyanobacteria https://en.wikipedia.org/wiki/Cyanobacteria
- rapind 4y agoSlow version of the Death Star. 1) Send Cyanobacteria out. 2) Wait a few billion years for a competitive animal to evolve and nuke the planet to pieces. 3) Profit! (mine the asteroids).
- mickdeek86 4y agoI hadn't even considered the Death Star as a giant version of mountaintop removal
- spinlock 4y agoI was thinking that I wouldn’t appreciate aliens sending crazy microbes to earth just to see what happens. It’s weird that NASA is funding the DEEP-IN part of the project but not the microbe part. IMO you cannot separate the two.
- spaetzleesser 4y agoYou can separate them. You want to send probes with sensors and get the data back. Just don't send microbes.
- mannerheim 4y agoDoesn't sound like the probe would be landing on a planet. At a fifth of the speed of light, there's no slowing down enough to do anything more than a flyby.
- elorant 4y agoAnd what happens if the probe crashes on the planet with that much kinetic energy?
- exitb 4y agoAt 1/5th of speed of light the probes would cover 1AU in less than an hour, so the visit in the area would be extremely brief. Is there actually a way to get any meaningful data out of it? Or is it just so we can say that we've "been" there?
- rthomas6 4y agoI wonder if it could unfurl a light sail when it got most of the way there to slow it down. Is that feasible?
- exitb 4y agoInteresting idea, but I don't think the sail would be nearly enough to counteract the gravitational acceleration caused by getting near the target system, let alone losing enough speed to enter an orbit.
- KineticLensman 4y ago>> Each spacecraft would be the size of a DVD disc Not much room for a light sail large enough to fully offset the power of the launch lasers.
- kadoban 4y agoIn short: no. It'd need to slow down enough to counter-act years worth of a laser specifically making it go faster. Without a laser on the other end, really no shot.
- SideburnsOfDoom 4y agoRegardless of travel speed, it would take a lot of energy to get matter or even any identifiable bits of data back from Alpha Centauri to here. I don't see any discussion of how they propose to tackle that problem.
- ncmncm 4y agoIt is never even hinted how any information could ever be communicated back to Earth. It makes me think the whole project is not serious, like launching Voyager with no Deep Space Network to listen. Are they hoping that over the 40 years it takes to get there, a solar-system-sized radio telescope would be built to listen? Even with that it is implausible.
- onion2k 4y agoIf there's intelligent life at the other end they're going to be serious confused about how some microbes built a probe.
- cletus 4y agoI love futurist content. Isaac Arthur's channel on Youtube is a fantastic resource for this. I'm convinced that a Dyson Swarm (ie orbitals around a star to near-fully capture the energy output of the Sun) is our inevitable future because it doesn't require any new physics or exotic tech. Specifically, solar power and stainless steel get you most of the way there. It just makes too much sense. This has all sorts of implications but an important one is how do you travel between stars. The rocket equation is bad news for interstellar travel. Getting to any significant percent of light speed (and decelerating at the other end) requires an insanely massive amount of energy that we really don't have any likely feasible method without exotic things like antimatter or black hole propulsion (yes, this is a thing). Even on vast timescales, you almost need viable nuclear fusion, which is far from a certainty. But these all assume you carry your fuel, which is the real tyranny of the rocket equation. Photos of course have momentum. Enough of them can be used as a form of propulsion, which is what the Starlight project is about. So one proposal for interstellar travel is so-called interstellar highways where energy from a star is concentrated to provide propulsion. You then only have to carry fuel to deceleate. Alternatively you can pre-build infrastructure to use the same technique to slow you down at the other end. Personally, i think this is likely the only viable method we've thus far conceived. I encourage you go watch this [1] if this interests you. [1]:https://www.youtube.com/watch?v=oDR4AHYRmlk https://www.youtube.com/watch?v=oDR4AHYRmlk
- JohnJamesRambo 4y agoRe: Dyson Swarm not needing new tech 1. How do you keep the swarm from hitting each other and staying in the same place and not crashing into the sun as you capture the near-full output of the star? 2. How do you get the power transmitted to our planet?
- ncmncm 4y agoThe planet does not need the power; it gets all it needs. It is used in space. They don't crash into each other for the same reason our satellites (mostly) don't: they are in selected orbits. But if we have not worked out aneutronic fusion by the time we would be able to build something like this, you might as well write off humanity. By then all the action will be out in the Kuiper Belt, where the truly valuable resource is: cold.
- barbegal 4y agoThe physics doesn't stack up for me. The spacecraft must be lightweight so it can be accelerated to high speeds but it must also have a very large area such that a large proportion of the laser photons hit it. This means a very thin disc shaped spacecraft (a few grams but with a few m2 of area). Whilst this may be able to be constructed it would be incredibly delicate for launch and I can't see how it would have the required strength to avoid it tearing apart under the force applied by the laser photons. A paper produced looking at the feasibility of such a system https://arxiv.org/pdf/1604.01356.pdf https://arxiv.org/pdf/1604.01356.pdf says >A critical issue will be the stability of the sail. There are a number of perturbative effects. These include laser instabilities and laser mode issues, differential forces on the sail and mechanical modes in the sail, heating of the sail and laser pointing instability. >This is a complex sets of issues that requires a significant amount of research and development. This will not be trivial. I believe these issues are show stopping rather than "not trivial" You can never fabricate a probe of small enough mass which has enough area for laser propulsion to work effectively whilst not tearing itself to pieces or overheating (at least not to anywhere near relativistic speeds).
- fnordpiglet 4y agoI have over 500 hours on kerbal space program and have been playing with the KSPIE mod that enables beamed power and sails. They definitely work.
- barbegal 4y agoOh yeah they work fine when you neglect certain critical parameters. How hot do your solar sails get in Kerbal? And what is the maximum torque between the sail and the spacecraft in Kerbal?
- simonh 4y agoI suspect a close proximity of tongue and cheek in that comment.
- fnordpiglet 4y ago
- Pxtl 4y ago> They would fly at one-fifth of the speed of light what? I thought most materials would be obliterated by the damage caused by traveling through the interstellar medium at such speeds.
- sliken 4y agoWould some be lost, likely. Would all have some holes in the large sails, sure. But some on board redundancy should let a decent fraction of them to survive. Keep in mind the lasers will boost the velocity for just minutes to hours, so you can launch many of them.
- pokstad 4y agoReminds me of the Staircase program in the book Deaths End (third book of the Three Body Problem trilogy).
- fallingfrog 4y agoI wonder- would an observer in the Alpha Centauri system be able to pick up the accelerating laser with a telescope? That would be a pretty powerful and tightly directed beam. If an observer did, they would have a few years advance warning and know the exact trajectory of the probe.
- sliken 4y agoExact? I've been hearing launch times in the minutes to hours before the probe is too far away to accelerate it enough to be worth while. The problem is lasers (on those scales) spread quickly so an ever smaller (even with perfect aiming) fraction of the laser energy will be delivered to the probe. I am curious if the red shift at 1% of the speed of light is enough to throw off the efficiency of the material that's designed for a specific laser frequency. For the same reason the cone of light will be larger than the orbit of any planets around Alpha Centauri. So the exact direction is tough, but that it's heading towards Alpha Centauri is easy. The formula for the angle (in radians) of dispersion: (The laser's wavelength)/(π × The laser's aperture)
- ck2 4y agoWhat's the effect on mass at 1/5th light speed? Ah okay, google says only +2% > A particle moving at one-fifth the speed of light (60,000 km/sec or 37,000 mi/sec) has a mass only 2% greater than its rest mass. When a particle's speed approaches the speed of light, however, the mass increase (called the relativistic mass increase) is significant.
- gzer0 4y ago> Currently, research models suggest that using this technology, a satellite massing 100 kilograms (220 lb) could reach Mars in 3 days, a significantly shorter time than the current transit time [1]. Incredible. This is simply incredible. I hope humanity succeeds here. [1] https://en.wikipedia.org/wiki/DEEP-IN https://en.wikipedia.org/wiki/DEEP-IN
- JPLeRouzic 4y agoThis means an acceleration of 85 g, what hardware can support this? What temperature the influx of energy will induce?
- varjag 4y agoA GPS guided Excalibur shell acceleration peaks around 12000g.
- JPLeRouzic 4y agoThanks I learned something!
- JPLeRouzic 4y agoPlease, did you achieve to power on your MS1201.02 single-board PDP-11 ? Thanks!
- varjag 4y agoHa! Nope, some months after the post I re-capped it and installed modern DIP switches. Then I stumbled on another specimen in perfect condition and grabbed that one. Both are still collecting dust on my projects shelf: never got around to powering either on, even though I have the power circuit sequence and schematics. Something to be said about spreading yourself too thin! :)
- JPLeRouzic 4y ago> Both are still collecting dust on my projects shelf: Ah, ah, it's something I know as well!
- spaetzleesser 4y agoWhy would you waste weight and send organisms? I can't see anything useful coming out of it. And it would be sad if these organism wiped out alien life. The probes need as many sensors as possible. It will already be super tricky to make any observations from a probe that goes at a tenth of the speed of light. And how do you get your data back from that distance without huge antennas?