Are we alone? Tiny spacecraft will head to Alpha Centauri to find out

https://www.cnet.com/news/sending-tiny-spacecraft-to-alpha-centauri

by ForHackernews • 8 years ago

190 216 8 years ago

cnet.com

DerekL• 8 years ago

The link goes to an entirely different article.

Jaruzel• 8 years ago

Seems fixed now.

ForHackernews• 8 years ago

CNET has some kind of infinite scroll thing that messes with what "page" you're actually on. I'm not sure if there's a better permalink?

Cheyana• 8 years ago

https://www.cnet.com/news/sending-tiny-spacecraft-to-alpha-c...

bumholio3• 8 years ago

This century, it will not. We are very far from a technology capable of achieving what Starshot proposes. Accelerating the spacecraft to a fraction of the speed of light using a laser would require power densities that would instantanously turn all known materials to plasma. The best mirrors and coatings are many orders of magnitude too dark. The required laser and energy bank would be, for all intents and purposes, a comics megaweapon capable of blowing spacecrafts from orbit, or, with proper space reflectors, incinerate enemy installations anywhere on the globe in seconds.

The craft would be completely unable to brake so it will pass past the target planets in a matter of minutes. It's unclear what kind of sensors could be employed to detect anything and we certainly lack the technology to beam and receive back signals sent by a postage stamp craft 5 light years away. Let me rephrase that: we haven't got even a theoretical model of a system that would allow communication at such vast distances with milliwatt power sources.

Needless to say, nobody is seriously working on this, nor will they for many decades at least.

overcast• 8 years ago

That's no Moon!

Razengan19• 8 years ago

If the craft is packed with instructions on how to get back to us, maybe we could get some sort of exchange going over multiple centuries.

On the other hand, if someone were to sent similar craft to us, would we even have a reasonable chance of detecting something that small without knowing exactly where, when and what to look for?

ʻOumuamua may have been a probe, yet even with our suspicions about it being something out of the ordinary, we more-or-less collectively yawned and went about our daily strife without making any effort to collect it.

[0] https://en.wikipedia.org/wiki/ʻOumuamua

madeuptempacct3• 8 years ago

I have been obsessing over Oumuamua as well, but there's just not that much information, and we won't be getting more. Then there was the fact that it was tumbling and wasn't emitting anything - one would expect radar scans or radio transmissions, or at least something.

bencompanion5• 8 years ago

ʻOumuamua is fascinating, I agree - but the most remarkable thing about it is that it's the first object like it we've seen, followed closely by the fact that it's taken us so long to see one. Most models predict these are pretty common - it's just our lack of spotting capacity that's stopping us seeing more.

As far as collecting, I remember reading a back-of-the-envelope analysis that suggested that we might be able to catch it if we made a really concerted effort. We might then be able to hit it with an impactor (or just smack the probe into it) and do some spectroscopy on the resulting dust cloud, but it's going way too fast in an inconvenient direction for us to be able to collect anything, slow down and return it.

bencompanion5• 8 years ago

On your other point - would we have a chance to detect something that small? No, absolutely no way, even considering that there would be a continuous 'stream' of these things spread out like beads on a string.

Say each one weighs a gram, and is 1m across - that's just impossibly small. The Hubble ST's resolving power means that it can resolve a 1m object (ie, make one pixel = 1m²) at something like 4000km away. In space terms, that is practically touching. In interstellar terms, that might as well be inside the planet!

Any transmitting that it might be doing would necessarily be very low power, which means it would need to be highly directional and pointed back the way it had come, behind what must be a reflector more reflective by far than anything we know how to build. Unless you managed to get its transmission pointed directly at you by being behind it, there'd be no way to see it.

After decades or more in the interstellar void, it would be about as equal to the ambient temperature as it's possible to be, and in any case, it's not made of very much 'stuff', so it would have no heat signature to detect.

Lastly, at 20% light speed, they would cover the average distance from Pluto to Earth in something like 36 hours. That's not a lot of time to search!

The only possible method I can think of would be to detect the results of these things crashing into dust within the solar system. How much of a 'puff' a gram of diffuse something travelling at 0.2c hitting a speck of rock makes I don't know. Still way too small to spot, I'm sure.

modzu• 8 years ago

yup. its an awesome idea and the most credible possibility for an interstellar probe but im so sick of reading these pop science articles that make it sound like it's about to launch. we still need to do science on these problems, we aren't at the engineering phase. that said, people are working on it:

https://breakthroughinitiatives.org/research/3

sofon2• 8 years ago

Project starshot does have a history, beyond this press release. And they have thought through the issues. There's a great youtube video here that goes into the details:

https://www.youtube.com/watch?v=bbi1hHPpTjY

They talk about using a 1km^2 earth based laser array to accelerate the craft. They also discuss using a 1W laser on the craft, and using that to transmit data back to earth (with a similar 1km^2 array to receive the signals).

They really seem to have thought through all the issues and come up with difficult, but plausible solutions.

blacksmith_tb• 8 years ago

I was wondering how much of that 100gW is lost in Earth's atmosphere - my naive assumption would be quite a bit, but maybe not so much that it would make sense to try and get the laser into orbit (also orbiting gigawatt laser would make everyone nervous, I imagine...)

bencompanion5• 8 years ago

Thank you - this article is interesting meat wrapped in lie-pastry.

The "will" in the title is just flat wrong. "Might possibly" is a stretch, even. People are sketching out the idea, enough that there are known but currently insurmountable problems in doing it. It's an interesting and promising approach in general though.

Some additional highlights:

accelerate the nanocraft with a 60,000-G force

We're going to make a package of sensors, transmitters, power source and sail that weighs one gram and can also survive 60,000g's of acceleration for multiple minutes? For comparison, the US Navy's ship mounted railguns accelerate projectiles at something like 15,000-20,000g, and those are 10kg of high-precision tungsten, and need to do nothing except not disintegrate.

The combined laser power needs to be something close to 100 gigawatts

If my maths are right, that's nearly the generation capacity of Japan (https://en.wikipedia.org/wiki/List_of_countries_by_electrici...). Granted, it wouldn't be required for long, but recruiting (or alternatively, storing) a whole-extra-Japan's worth of energy for even a few seconds is just completely ridiculous. We would need large-scale orbiting solar or commodity fusion power before we could even dream of anything like that.

wollstonecraft• 8 years ago

A normal tank gun is 30,000 g and electronic fuzes work just fine for those.

balt_s• 8 years ago

a comics megaweapon capable of blowing spacecrafts from orbit

So it does have some use other than just launching probes..

bumholio3• 8 years ago

I'm not sure that's an advantage. It adds a strong political component to something that's unlikely to be a cost effective weapon. So foreign powers will contest it and domestic powers will be unlikely to put their weight behind it. Kind of like nuclear rockets - in theory a workable technology, yet so controversial nobody will touch it.

Roboprog2• 8 years ago

For sure. Something like this might be useful to explore the Oort Cloud / Kuiper Belt, but I don’t expect to see anything like a star probe built in my lifetime.

Might be interesting to couple laser powered “solar” panels with an ion drive, though :-)

Razengan19• 8 years ago

There is no way that we are "alone" in a universe estimated to have practically infinite planets.

However, the distances between stars and the very short windows of time in which life may thrive (remember that we may have never known about the dinosaurs on our very own planet if we didn't discover their bones, and we will never see them again) means that we may never meet any other life.

metalliqaz• 8 years ago

It's certainly possible if the probability of developing intelligent life is Infinitesimal.

Razengan19• 8 years ago

We don't know all the forms that "life" or "intelligence" can take.

We certainly do not have any proof that it's impossible for life to be different from us, and we're already in the process of creating intelligence that's different from ours.

Our understanding of where life can thrive still gets challenged by discoveries on our own planet, or the experiments in our own labs, like the one on metal-based "cells" [0] that I read about recently.

[0] https://www.newscientist.com/article/dn20906-life-like-cells...

mihaifm4• 8 years ago

This is a very optimistic view, but there are plenty of theories claiming otherwise. Check out the Fermi Paradox [1], or the Rare Earth Hypothesis [2] for a more detailed view on the problem.

To be honest the easiest explanation for the Fermi Paradox is that we are indeed alone as an inteligent civilization. If we were just an average civilization there should be plenty of evidence of more advanced civilizations across the galaxy, because probabilistically they would be millions of years more advanced than us.

[1] https://en.wikipedia.org/wiki/Fermi_paradox [2] https://en.wikipedia.org/wiki/Rare_Earth_hypothesis

Razengan19• 8 years ago

Honest question: Do we have the means to detect conclusive evidence of life on Earth itself from even "only" as far as, say, Pluto, without knowing exactly what to look for?

bena3• 8 years ago

I've never liked the Fermi paradox. It seems terribly contrived. It assumes way too much. That space colonization is inevitable and/or that strong AI is also inevitable.

What if it's not? What if it's an intractable problem?

What if technological advancement isn't exponential? What if it's more of an inverse tangent? A slow start, an explosive middle, then a long finish with an upper bound.

We have absolutely no other examples to base any assumptions of technological societies on, so why do we get "space colonization" and "independently thinking machines" for free?

ChrisBland• 8 years ago

To the single cell organism; the worm looks to be advanced and complex. To the worm; the human looks to be advanced and complex. Its possible we are still way down on the intelligence chain and too dumb to realize that we are in fact the worm in the scope of the universe

gldalmaso• 8 years ago

Maybe the oldest and most advanced civilizations decided to go tribal.

Maybe they are so advanced that they can hide their trail so belligerent civilizations like ours do not encounter them.

I don't think the easiest explanation is to assume that there is any sort of naturally occurring event in the universe that is one of a kind, save maybe for the big bang.

SmellyGeekBoy• 8 years ago

There are civilisations on earth (uncontacted tribes) who are completely unaware of the existence of modern society. With this in mind your view seems incredibly naive.

cthalupa• 8 years ago

There might simply be no way to travel at, or even near, and much less faster than, the speed of light, in which case the universe could be full of life that we will never contact or meet. Life might be rare enough that it's unlikely in any single galaxy.

WilliamEdward3• 8 years ago

That theory doesn't account for the fact that the laws of physics prevent anything from traveling faster than the speed of light. because our galaxy is 100000 lightyears long by itself, it would take 100000 years for an advanced civilization just to get to us let alone cross their own galaxies. It's highly possible other life doesn't exist but the reason we can't see them is because space is way larger than you think it is and takes a long time to travel across.

MichaelMoser1234• 8 years ago

The Fermi paradox assumes that there is infinite progress, what if going interstellar is just too hard? (Warp drive too hard and going such distances directly just impossible) What are the incentives to go interstellar once a species has colonised it's solar system?

amf12• 8 years ago

The universe is 13.8 Billion years old, so we can only observe the universe 13 Billion light years away. However the universe is practically infinite and much larger than the observable universe. It's not possible for us to detect a galaxy and a civilization (if it exists) in the said galaxy outside the observable range. Similarly, for the said civilization we lie outside that observable range and they can't detect us because nothing can travel faster than the speed of light.

Now imagine, how huge the unobservable universe is. Probabilistically, it is quite possible for a civilization (or multiple) more or less advanced than us to exist far, far away, or may have existed some point in time. But none can detect each other. Its even possible for a civilization to exist in the spheres of observation of other civilizations but so far away that its almost impossible to make contact. 13.8 Billion years is not a long time on the scale of the universe, but it is also a long time on evolutionary scale for a civilization to have existed and have been extinct.

babuskov2• 8 years ago

There is no way that we are "alone" in a universe estimated to have practically infinite planets.

Maybe there is a lot of space out there, but not enough time? Maybe the universe is still pretty young and it takes a lot of time to go from zero to intelligent life that knows how to contact each other over great distances.

Razengan19• 8 years ago

but not enough time?

Or too much time, between different epochs even on the same planet.

We are intelligent. We know dinosaurs existed. They stood where we stand. We cannot contact them, we will never touch them, and we will never fully learn about them, nor they us.

senorjazz• 8 years ago

Maybe each galaxial species is given the perfect planet for them. Distance to other life is so great to avoid one planet species from destroying another.

Which considering the appalling job we are doing of caring for our home planet is a good thing. Because if humanity ever finds another species, our track record is pretty abysmal. God only help them if their planet contains a resource we covet

Will_Parker• 8 years ago

There is no way that we are "alone" in a universe estimated to have practically infinite planets.

What if we are a random sample of conscious life in the space of all possible universes in a multiverse? Many of them will have intelligent life in many places, but the majority have the parameters just tweaked enough to touch the edge and only produce one. Couldn't we live in one of those?

(And there is near certainty a given tuning of the parameters produces none but obviously we can't be in one of those.)

magduf3• 8 years ago

This is exactly why we need to invent a device that allows us to travel, or "slide", between alternate universes.

simonh6• 8 years ago

If only one in a thousand stars have planets that can support life, only a thousandth of them develop complex life, only a thousandth of them avoid extinction events, only a thousandth of them develop technology, only a thousandth of them avoid destroying themselves somehow.

That would give us about one civilisation in every 10,000 galaxies. There are actually a lot more possible stages than that too, I've seen estimates that reasonably put our existence in the observable universe at all as a low probability event and maybe they're right. I've swung either way over the decades. There is a reasonable case that long term technological civilizations might be extremely rare. It's not a foregone conclusion that we are one of many.

Personally, I have no idea. It could go either way, but the Fermi Paradox does tend to indicate in the pessimistic direction at least with regard to our own galaxy. The problem is once you say technological life is rare at the one galaxy level, it only takes a few extra stages and a few extra low probability multipliers to make any life anywhere pretty unlikely.

FireBeyond• 8 years ago

You leave out the time dimension. The universe is what, just under 14 billion years old, and intelligent life on earth that can meaningfully seek out such things is what, 100 years?

That's another remarkably small window in time for us to discover anything - what if a civilization died out a million years ago?

csomar• 8 years ago

There is no way that we are "alone" in a universe estimated to have practically infinite planets.

That's very frightening on its own. Assuming the universe is practically infinite, there is another identically similar earth in this universe where another guy that has the same microscopic details as me writing this comment.

mabbo2• 8 years ago

The problem is that humans, you and me included, are very bad at extremely large and extremely small numbers.

We don't have infinite planets. We have 10^21 stars, roughly, and some constant P average planets per star.

If the odds of life are 10^-14 per planet, and the odds of intelligent life are 10^-7 per life hosting planet, and we presume every star has one planet that might support life, then in the 10^21 stars in the universe, we'd expect only one intelligent life. That is one possibility!

But we simply don't know what the odds of life and the odds of intelligent life are in the slightest. We don't even know what range of possible values are reasonable. And humans are so bad at contemplating numbers like 10^21 and 10^-14. They're too extreme for one to think of them rationally.

And saying "well, it happened here, be it must be common" is selection bias- we can only contemplate the problem because it happened here.

The right answer is to get more information to improve our estimates of the probabilities. If we can find life at Alpha Centauri, that would either be a hell of a coincidence, or a very good indicator that the probability of life given a planet is high.

Razengan19• 8 years ago

If we can find life at Alpha Centauri, that would either be a hell of a coincidence, or a very good indicator that the probability of life given a planet is high.

Why would finding life on just one more planet – out of the 195 or so "worlds" that we know about, including moons – suddenly make "the probability of life given a planet" high?

By your own reasoning, whether we find life at Alpha Centauri, or do not find any life there, will not really change the probability of discovering future life or intelligence among the rest of all the 10^21 * P planets.

We could always just keep saying that "There are only 2 planets in the universe with life. No more." "There are only 5 planets in the universe with life." and so on and on.

robodale• 8 years ago

It's "stories" like these I would read as a kid very early 80's, probably in Popular Mechanics magazines or similar.

Depicted in these magazine articles and artist renditions: in the future (certainly by the 2020s!), we will have bases on the Moon, maybe even Mars, and rotating space stations... all the while wearing stylish futuristic fashions (yet still looking very much 70's), the women sipping from glasses of champagne and laughing to each other while in the background the men play some yet-to-be-invented handball game.

bena3• 8 years ago

I mean, the biggest failure of prediction is that women seem to laugh at salad rather than champagne.

It always seems as if we're just 50 - 100 years from "the future".

Lost in Space takes place in 1997 when we were about to colonize space. Or as we know it, 21 years ago.

The original Blade Runner takes place next year. When we'll have space colonies and humanoid androids to work them.

And according to Star Trek, we've weathered the Eugenics War and have 31 years before World War III and the post-atomic horror. But in just 45 years, Zefram Cochrane will invent the warp drive.

Not to mention the countless flying cars we'll have as we go eat all of our meals in pill form.

brightball• 8 years ago

The 80s Transformers movie takes place in “It is the year 2005”

T4NG• 8 years ago

I'm very curious to know why you were downvoted

dekhn• 8 years ago

Hahah yes, for years I saw these pictures (https://en.wikipedia.org/wiki/L5_Society) and developed unrealistic expectations of human space exploration.

eganist• 8 years ago

I don't know if they were unrealistic so much as they didn't anticipate the cataclysmic demotivation that we as a planet incurred with the end of the cold war.

JKCalhoun2• 8 years ago

The Don Davis painting at the link you provided is so nice. Then below is such a crappy CG image...

Man, I love the old "artist's concepts", hate the new CG.

schiffern• 8 years ago

Here's a lot more of the space colony art commissioned by NASA: https://settlement.arc.nasa.gov/70sArtHiRes/70sArt/art.html

ijidak• 8 years ago

Wow. Yes! I remember this.

It's also amusing how much humans are effected by century and millennial boundaries.

There was a show in the 80s, on I think Discovery, called Beyond the Year 2000.

As a kid it seemed like the simple fact that we were entering the next millennium MUST be meaningful. And popular media portrayed it that way.

But 15 years is 15 years. Doesn't matter what boundary is crossed. Hahaha.

I think that's part of what even got people worked up about Y2K. It's a new millennia! Did we plan for it?!?

Anyway, my point is, I think the millennial boundary may have influenced excitement about space progress as much as other forms of irrational optimism.

Plus, gravity is hard.

davidivadavid• 8 years ago

Beautiful 70s Scifi Art: http://70sscifiart.tumblr.com/

madza• 8 years ago

Thank you. That is a great collection and brought back some very good memories of some great stories.

I have a large collection of old science fiction books (60’s and 70’s) from spending a lot of time in second hand book stores.

Growing up before the internet and the explosion of the genre in the 90’s that use to be the only way to find new books or authors.

The art of sci-fi book cover has certainly lost something...if only for being more pc.

JKCalhoun2• 8 years ago

Syd Mead.

And everyone else can go home. ;-)

_0w8t• 8 years ago

In 1990 when I was finishing school I bet with my classmate that there would be a permanent Moon base in 2010. As the result my much more practical buddy got 1500$ from his investment into sceptictical thinking.

tzs• 8 years ago

Did the bet specify that it would be a human base? If not, and if $1500 is enough to be worth having your school buddy think you have become an idiot or dishonorable, maybe you could have tried to argue that the secret alien outpost [1] on the far side counts and demand that your buddy pay you.

I assume your friend would reject that, but unless the bet specified a procedure to use in the case that the participants could not agree on the outcome, it might have been enough to void the bet at least.

Also, was the bet in writing and signed? If not, and if you are in a jurisdiction that has something like the Statue of Frauds [2], you might try to argue the bet is invalid because the Statue requires contracts that cannot be performed within one year (other than indefinite contracts) be in writing and signed.

The 2010 end date on the contract arguably makes it not of indefinite duration. The "cannot be performed within one year" is harder. It doesn't mean that it has to be performed within a year--just that it is possible.

For example, if I make a contract with you that says I'll pay you $1000 if in the next three years your bicycle is stolen and not recovered within two weeks. Because it is possible that your bike could be stolen in the next year, this contract can be performed in one year. It doesn't matter that it might not be.

Would it be possible in 1990 for a permanent Moon base to be deployed within one year? It may have been physically possible, but it was certainly politically and economically impossible. For Statute of Fraud purposes, is it good enough that it could happen even if it would require worldwide cooperation on an unprecedented scale? Or does it have to have a non-negligible chance of actually happening?

[1] https://www.dailystar.co.uk/news/latest-news/601628/Dark-Sid...

[2] https://en.wikipedia.org/wiki/Statute_of_frauds

bdamm• 8 years ago

Meanwhile, the $1000 bet I made with my college buddy that cancer would (not) be cured by 2022 is still very much up in the air.

magicnubs• 8 years ago

https://reddit.com/r/retrofuturism is good for these

barking• 8 years ago

All the developments we've had since 1969 feel more like improvements of what was already invented. Within living memory of an (old) person alive then would have been the birth of nuclear power, powered flight, the telephone, car phones, electronic computers, radiography radio, tv, the internal combustion engine, satellites and the first men on the moon.

rqs2• 8 years ago

we will have bases

If you change "have" to "could", then maybe it's true again, according to this video at least: https://www.youtube.com/watch?v=3iMlOH6hdOw

It's quite sad to see politicians make space exploration this hard.

Even more sad after you find out politicians also the source of so many wars on the Earth.

bfuller• 8 years ago

we will could bases?

karimdag• 8 years ago

Relevant (and quite enjoyable) read: The Three Body Problem (novel) https://www.amazon.com/Three-Body-Problem-Cixin-Liu/dp/07653...

holman• 8 years ago

This book series fundamentally changed how I view the question of life in the Universe.

I really loved the series. I can see why some others weren’t into it, but I think it’s been my favorite books I’ve read in years and years.

ajuc5• 8 years ago

My problem with the series is the premise that invasion of another star system is worth it.

With all the resources Trisolarians put into colonization of Earth, and all their superior technology - they could've made space habitats that had perfectly safe orbits around whichever star they prefer, and put all of their citizens on them.

What's the point of risking mutual destruction by hunter in the dark forest (and we know they were afraid of it since the start), if you can create habitats in your own star system, or choose any nearby uninhabited star system if the 3-body-problem is really making it impossible to put these in your own system (and realistically - it wouldn't be so bad, just make a dyson swarm around the whole system.

madeuptempacct3• 8 years ago

This is the one book I have seen praised here endlessly. I am sincerely hoping it can stand with Neal Stephenson's work. I don't think there is any other author I can recommend unequivocally.

tralarpa• 8 years ago

hoping it can stand with Neal Stephenson's work

Thanks, always looking for new stuff to read. (edit: not really new, but new to me :)

Concerning The Three-Body Problem, I found it a bit disappointing. Great build up with a rather traditional solution making some things of the build up looking a little bit silly.

germinalphrase• 8 years ago

I found the ideas were interesting, but the writing (plotting/characters) to be ho-hum. It’s a translation, of course - but I’m not sure I would rate it quite as highly others here.

zengid• 8 years ago

If you like Neal Stephenson, you'll like Cixin Liu (especially when translated by Ken Liu), but you'll have to give Liu a fresh chance and let his work be its own thing. I love NS's work, and I've really enjoyed Cixin Liu's trilogy.

Three Body Problem is very thrilling to read; fast paced with a lot of cliff hangers, and excellent world building. The sci-fi/speculative bits are extrodinary, and although the characters can sometimes feel like their only role is to give a 'first person perspective' of the science, Liu can surprise you with the emotional depth that his characters exude.

The Dark Forest is in my opinion harder to get through than Three Body Problem, but the payoff is extraordinary. The pacing is slower with more world-building, and the perspective bounces around between a lot of characters without much forward movement. I had to put it down for a while and read some other books before I built up the motivation to finish it (it helped that I already bought the next book, so I felt guilty not finishing).

Deaths End, the third book, is unbelievably amazing. The pacing is more similar to Three Body Problem, and the science is astounding. All of the patience necessary for Dark Forest pays off because Liu is able to bring his world-elements into a mesmerizing display of action and conflict. I'm only half-way through and I've lost count of the number of times I've had to take pause and simply exclaim "Wow!".

test6554• 8 years ago

Yes, if there's other life in the universe, then we absolutely don't want to announce our presence to it. Due to exponential growth in technology and the old age of the universe, we are the plankton of the universe and they are likely the fish.

jerf2• 8 years ago

I used to worry about that a bit when we discussed this a year or two ago, but then I realized that Earth has been broadcasting the fact that it is inhabited to any civilization only slightly more sophisticated than ours (like, literally only by a couple of years) who can see spectroscopy of our atmosphere when we transit in front of the Sun. Earth has been broadcasting that it has free oxygen for nearly two and a half billion years and we have no evidence of any attack.

lolc3• 8 years ago

That analogy doesn't work for me. Why would somebody that can cross space stop by us? They don't need to eat exactly, do they?

nategri• 8 years ago

The part where the Trisolarians try to make the Special Thing was hands down one of the dumbest things I've ever read in science fiction.

The first 3rd of the book that dealt with cultural revolution fallout was awesome, though. But yeah---back half was bad enough to ruin the whole thing for me.

salutonmundo3• 8 years ago

Surely nothing can top the latter half of Orson Scott Card's Xenocide.

Semiapies3• 8 years ago

I thought it was hilarious, myself. The Amazing Artifact treated as a government project.

salutonmundo3• 8 years ago

I liked that book, but if anything, it made me of the opinion that life in the Centauri system (or any three-body star system) is extremely unlikely.

Semiapies3• 8 years ago

I liked the novel, but the whole setup is written under an inaccurate understanding of how the Centauri system is arranged. Proxima is a long way out from Alpha Centauri A and B (0.21 light years), orbiting their mutual center of mass, and A and B themselves are a fair distance apart (from 11.2 to 35.6 AU). Any of the three stars could have planets in close stable orbits; we already know Proxima has one.

ETA: Actually, we know of another one around B.

https://en.wikipedia.org/wiki/Alpha_Centauri#Planets

tinnet• 8 years ago

hope the space dust does not wipe off the writing on the front: "this is not a laser powered bullet to destroy your planet, should totally just fly past, we did the math"

lolc3• 8 years ago

Haha, any atmosphere at all would disintegrate those things. Earth sees that calibre every minute. We'll totally aim right at the planets and won't hit them anyway.

Edit: Well, I forgot the relativistic speed that ball would be traveling at. So if the planet's inhabitants actually lived in the upper atmosphere some might actually get burned.

mattferderer• 8 years ago

This article introduces more questions than it answers to me.

How do you travel that fast & not disintegrate or crash into something?

Was Mr Manchester's experiment done using a laser to launch?

Has this been done before at any scale? Even pushing an item a few hundred feet up?

Is there a timeline for this to even get attempted?

I think it sounds really awesome but that makes me wonder if any of this is feasible soon. Sending tiny Raspberry Pi like devices into space at fast speeds that could do cheap experiments more quickly, that would be nice.

neurobashing• 8 years ago

Not to mention, where are all the other Bracewell probes from all the other interstellar civilizations? If there's life shouldn't the local area be teeming with them, since they're cheap and easy for any culture that can do spaceflight? (also, for fans of The Expanse, something something protomolecule)

snowwrestler2• 8 years ago

How the heck would we detect a 3 foot spacecraft that weighs a few grams, passing anywhere through the Solar System at speeds over 10% of light?

We might be getting them once a week and we would have no idea. We can't even find or track most of our own asteroids, and they're already in solar orbit.

sp332• 8 years ago

The KickSat was deployed as a 3U cubesat into orbit. The point was just to launch a ton of satellites at once, not to test some kind of propulsion tech.

The relevant propulsion research was the Ikaros http://global.jaxa.jp/press/2010/07/20100709_ikaros_e.html It accelerated at 1/10 G using only solar radiation.

maxxxxx3• 8 years ago

Are they planning on sending signals back? Also how much observation can you do with a little spacecraft that moves through a solar system at that speed?

darkstar999• 8 years ago

Read the article to find out!

maxxxxx3• 8 years ago

I read it but it seemed very light on detail. How would they use the laser to get a signal back?

throwaway456321• 8 years ago

They're dreaming !

lucb1e• 8 years ago

TLDR for those who are already familiar with the idea and just want to know the details: it'll travel at .2C, taking 20 years (4ly*.2), and there is no launch date. It seems all still theoretical at this stage, though they're pushing some serious funding. To report back they "hope" the spacecraft can use lasers and we will "probably" hear a few when a bunch of them report their measurements back.

repler• 8 years ago

I don't recall there being any exoplanets within the habitable zone at Alpha Centauri.

Grue3• 8 years ago

If it's going to fly at such a large speed, what is the proposed mechanism to stop it? This thing would instantly burn as soon as it reaches any planet's atmosphere. Could Alpha Centauri's gravity field capture this spacecraft somehow? Doesn't seem likely.

DowsingSpoon• 8 years ago

I don't believe there is an intention to slow down or stop.

zamalek• 8 years ago

I wonder if the laser could be used to clear space debris.

wlesieutre• 8 years ago

Probably yes, https://en.wikipedia.org/wiki/Laser_broom

Finding and tracking very small/fast debris is a different matter, but if you can find the debris and keep a laser aimed at it you can alter its orbit.

HillaryBriss2• 8 years ago

This article has many insights I've never seen before.

This is my favorite: "If the dinosaurs had a giant laser, maybe they'd still be here"

HillaryBriss2• 8 years ago

Given that an approach like this could be implemented even on a lower power basis, wouldn't we use it first for super fast, super frequent investigation of planets and their moons within the solar system? Isn't that the low hanging fruit here?

SubiculumCode2• 8 years ago

It seems that while traveling that fast it would be hard to collect good data from the system, but I am no physicist.

ChuckMcM4• 8 years ago

I always wonder about programs that require building a 100GW laser that can target any point in the sky above it. While I"m sure there are many uses for such a device, clearly one of them is disabling satellites. Which makes the creation and operation of such a device destabilizing at a minimum and more likely fairly provocative.

walterbell• 8 years ago

100GW laser governed by Facebook CEO and VC. What could go wrong?

Roboprog2• 8 years ago

Oh, on the ground? I thought the article mentioned having the lasers in orbit, presumably to avoid atmospheric blurring.

So it’s not just things in orbit that are targets, it’s stuff on the ground, as well.

Be the first on your block to have one, I guess.

ChuckMcM4• 8 years ago

Ground is where the power supply is. Although an orbital laser with enough solar panels would probably work as well.

Same issue though, except now you have a 100GW laser that is able to point to many different places on the ground from where its orbital position.

Even if it is short duration, 1mS @ 100GW imparts as much energy as 100MW over 1 second, or 1 MW for a bit longer than a minute and a half.

travisoneill14• 8 years ago

Seems like overkill for shooting down satellites. IIRC the US and China have already demonstrated this ability so I don't think it would add that much as a weapon.

ChuckMcM4• 8 years ago

Don't under estimate the value of being able to shoot down a satellite with no advance warning. Existing anti-sat weapons are typically launched from a platform that is visible/trackable long before it can actually kill a satellite.

shmerl• 8 years ago

What about using ion thrusters for such purpose?

acqq• 8 years ago

Also see:

"Is Humanity About To Accidentally Declare Interstellar War On Alien Civilizations?"

https://www.forbes.com/sites/startswithabang/2018/08/07/is-h...

"aiming to the level-of-precision needed to pass close to (but not collide with) a target planet is virtually impossible. The “cone of uncertainty” for any trajectory will include the planet we’re aiming for."

"A planet getting hit by a ~1 gram spacecraft moving at 60,000 km/s is going to experience the same level of catastrophic effects as a planet getting hit by a ~1 tonne asteroid moving at ~60 km/s, the equivalent of which happens on Earth just once per decade. Each strike would hit their world with the same energy that the Chelyabinsk meteorite struck Earth: the most energetic collision of the decade."

lolc3• 8 years ago

I don't think a meteorite can be compared to such a tiny ball. The ball will disintegrate when it's still 100km up. You get an intense flash. But I don't think shock waves travel much up there.

S_A_P• 8 years ago

I am curious as to how the radio tech will work for these things. Im skeptical that something super low power will be able to send us back some pictures from that distance? Is our current tech that good?

clarkmoody• 8 years ago

It will use lasers to send the data. An interesting proposal to use the sail as an antenna here: http://breakthroughinitiatives.org/forum/13?page=4

espinchi• 8 years ago

Here's a bunch of startup ideas: http://breakthroughinitiatives.org/challenges/3

I'm mostly kidding. These are hard, hard problems, much better suited to research organizations. Exciting stuff!

salutonmundo3• 8 years ago

"If the dinosaurs had a giant laser, maybe they’d still be here. - S. Pete Worden"

aaaand it's going right in the quotes file.

georgeecollins• 8 years ago

A giant laser might also have saved the Aztec civilization.

pfdietz• 8 years ago

If there is intelligent life on the star next door, the Fermi Paradox would bite extremely hard. So, no, we're not going to find intelligent life there.

ufmace2• 8 years ago

What I want to know is how they plan on steering these things. How do you get a multi-gigawatt laser on Earth to not only hit a ping-pong ball sized thing in space, but propel it in a particular direction, precisely enough that it will pass through the inner solar system of a star system 4 light-years away? Wouldn't an encounter with a tiny bit of gas or something near our solar system cause it to be like a few billion miles off target?

0bfus• 8 years ago

If they're passively propelled, then it can just become a numbers game. Send a thousand and hope for the best maybe?

mLuby• 8 years ago

Recommend reading TFA:

Think of it as a large pingpong ball with computers and cameras pointing in different directions. The big advantage? The spherical shape, coupled with a "hollow" laser beam that's stronger toward its outside edge, could be naturally centered on the beam throughout the acceleration.
"Imagine blowing a piece of paper straight up. It's going to fly off the beam unless it's perfectly aligned," says Zac Manchester, a Stanford professor and Starshot engineer who's researched the subject and already launched a 1.4-inch square spacecraft into Earth's orbit.

istjohn• 8 years ago

But also from TFA, the lasers will stop after the spacecraft travels about ten times the distance between the Earth and moon. I think the question still stands, is it possible to expect anywhere near the needed precision without some kind of active steering over the four light years (minus ten moons) of space that must be traversed? It certainly must be a limiting factor in the utility of this scheme. I can't imagine using this tech to execute a planned fly-by of an extra-solar moon, for example.

ufmace2• 8 years ago

I did read it. That's why I asked the question. That all sounds rather vague and hand-wavey compared to what I expect it to take to come near the inner planets of a solar system 4 light-years away.

MichaelMoser1234• 8 years ago

i wonder how they deal with the possibility of collision - at this speed and distance you will have a significant chance of bumping into something in interstellar space. Also you will have to slow down the spacecraft somehow, how would they go about it?

Are we alone? Tiny spacecraft will head to Alpha Centauri to find out

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