Hacker News Reader

Comment by sixdimensional | Hacker News Reader

Seeing this news is a nice tribute to Ed Stone, who was one of the core project scientists for Voyager and recently passed [1] (and all those who work/worked on the program).

I had the pleasure of meeting Dr. Stone at a public NASA event many years ago. I asked him, perhaps a silly question: "what does it feel like to know you built the furthest man-made known object in the universe?".

He paused for a moment, after which he responded, with a smile: "Pretty darn good".

RIP, Dr. Stone and go Voyager go!

[1] https://www.jpl.nasa.gov/news/ed-stone-former-director-of-jp...

View on HN

I’m interested in the biopic about the engineer that fixed this. Anyone know anything?

Not so silly, considering it’s almost certainly always going be the furthest man-made object in the Universe.

I hope not-- it may take a long time, but I hope we laser accelerate some probes really fast.

Eh - to send it where? Even laser accelerated, even if it gets to 0.1c, where is it gonna go?

Edit0:typo

Alpha Centauri. See Breakthrough Starshot and other such potential missions.

https://en.wikipedia.org/wiki/Breakthrough_Starshot

Obviously, no need to answer further, I'm just being grumpy I imagine.

Man - why go there? What are we looking to learn?

Do they have the kilometer Gw phased array yet?

The meterwide/gram weight sails?

The chips that weight one gram with comms and cameras and all that?

And just to clarify, they can't flip and slow down, so it's a 0.15c flyby of alphacentauri, entirely automated. So hopefully the code does't fuck up in this alien environnement without human help.

What do they expect to learn at that speed and with such small sensors? Like a picture of the planet, like we get telescopes? I sure wonder the speed at which that's going to transmit data.

I'm just seeing "proof or concept" but this is mostly concept and no proof.

And if this is "step one" of interstellar travel, what's step two?

Edit0: Just reading the wiki this is so absurd -atmospheric turbulence is a challenge to deliver te GW laserb- so were planning on building a km phased array in space to accelerate the swarm. Just this itself is way way beyond realistic. Doesn't this breakdown at napkin math levels?

Voyager 1 was launched in 1977 and its code hasn’t broken.

Construct a stack of starships in orbit and you would be able to get a probe there. It’s never about the technology, it’s about whether someone cares enough to spend the resources.

What do you mean about the starship stack? That's the array?

For Voyager, I'll argue that it's mission is much simpler (doesn't need to aim forthe position of something 30 years in the future) and that we keep transmitting to it (the sheer distance will limit our involvement as the delays between transmissions grows). It's also not going at 0.15c, where it needs to do the calcs very quickly.

I'm not sure how easy it would be to make a km wide Gw array on Earth, but building and powering it in space seems much, much harder. Just harvesting the GW takes 3 million solar panels. Just getting that to orbit seems unlikely. Even with very generous 1kg per panel we get 3 million kg to put in orbit, or 21 Falcon Heavy at max payload, or two years of putting nothing but solar panels up. It's so much.

And then how much money is going to make the gram scale probe appear?

Edit0: to clarify, the probe will have less time than the duration of the blink of an eye to take measurements. That's limiting what you can learn AND makes it very hard to aim correctly.

When you have the means to harvest and beam out a GW in space, it is not like the only use for it would be sending those probes. Seems like damn useful infrastructure for almost anything else. So, we can expect the hurdles to be overcome for other purposes as well...

Betting against humans making breakthroughs is usually a bad bet. As the saying goes: "You can say 'it can't be done' all you want, but please stay out of the way of those who are doing it."!

Militant use first if we are realist. Paid me or I will shoot you with 1Kw. I guess doing it on the far side of the moon is essential. :-(

You know the ultimate answer.

Because we can.

> Man - why go there? What are we looking to learn?

The how is a much bigger problem than the why. It would be great to have some closer sampling of Proxima b, such as images, spectroscopy, etc. You won't get much on a 0.15c flyby, but you'd get something, hopefully. No room for error of course, with a several year round trip for commands.

Having some sense of the planet could inform a colonization plan that's likely to have even bigger problems with the hows rather than the whys.

But the whys are clear. Even if it's not actually feasible.

> Doesn't this breakdown at napkin math levels?

Only in terms of cost; there's nothing that seems to be fundamentally unobtanium here. The question is whether it can be come cheap enough to be viable.

I think the gram class probes with gram class sails that are a meter wide are outside the scope of feasibility today and would require unobtanium. Shielding too.

> there's nothing that seems to be fundamentally unobtanium here

Don't you think this is begging the question? The entire history of humanity is a lengthy series of discoveries that people of times past would have little reason to think possible, and in some cases are revolutionary enough that it would likely have been all but impossible for people of times past to even think of them.

Then there's just the boring things, like aspirin. If not for the willow tree, it would not exist today. Ancient medicine dating back 2400+ years recommended chewing on willow bark to treat fever or pain, and indeed they were right. Of course we can now easily synthesize it, but that's not always a given for every compound or 'thing' imaginable, to say the least. For an obvious example, see: uranium.

And now factor in how extremely negligible our knowledge of anything outside of our own planet is. We've been sending probes and rovers to Mars since 1962. We only discovered the soil on Mars was relatively moist (2% water by weight) in 2013! 50+ years to figure out there's water in the soil. And the latest drills can only go a couple of inches deep and are scarcely used in any case, because they tend to break. It's impossible to know what you don't know, but I see every reason to think that it's probably quite extensive.

[1] - https://www.space.com/22949-mars-water-discovery-curiosity-r...

?? I think you've misread my post.

I'm saying that the fundamental things required in order to launch gram-scale interstellar probes don't seem out of reach; that largely something close to the requirements could be made at great cost today, and making a mission practical is mostly about cost optimization and economies of scale.

I think largely whether we do it in 50 years comes down to whether we've wiped out a lot of our economic output by then with strife, and whether we still consider exploration worthwhile to spend a lot of money and reources on.

Haha, yeah I absolutely did. Reading his post and then your response it seemed to me to be a claim that there's nothing out there to discover, as opposed to there being nothing in the way of this means of exploration.

To the nearest interstellar object, when we will find one close to us. It's much more interesting than another star, because it may preserve the history of our galaxy in it deposits.

A very cynical take. I expect we’ll pass it in 20-30 years.

Voyager 1 has had an almost 50 year head start, and it was launched with a series of gravitational assists that are only possible every few hundred years. There is 0 chance anything will catch up to it in the next 50 years, and probably for several hundred more years after that, if ever.

That’s a really pessimistic take. Voyager 1 moves at ~17 km/s (and slowing down but it doesn’t really matter). That’s on the order of 0.0001 c and indeed just a half of Earth’s orbital speed, so a part of the year the probe is actually getting closer in Earth’s frame.

A one-kg nanoprobe attaining 0.001 c would be perfectly feasible with today’s tech and would overtake Voyager 1 within a decade. Breakthrough Starshot proposes laser sail acceleration of gram-scale probes to > 0.1 c, a thousand times faster than V1, and nothing in the design requires fundamentally new tech. Such probes would claim the distance record in a few weeks of travel, no matter whether they’re launched twenty or fifty or a hundred years from now.

What scientific return are we getting from a gram sized probe moving at 30,000 km per second?

Today: almost certainly nothing In a decade: almost certainly very little In a century: almost certainly more than the Voyager

Assuming climate change doesn't prevent any kind of launch or most further research.

Wouldn’t the reduction in atmospheric density due to warming make it easier to reach orbit, etc?

Yes but widespread flooding, drought, crop failures and economic collapses etc. would make it much harder to devote resources towards such launches.

Modern silicon design with mems sensors I suspect could do an awful lot with a gram.

Also, at this scale, not much can be done by hand, so you can make hundreds of them for not much more cost than doing one.

Doesn't modern electronics require massive shielding?

e.g. you would need too much shielding and would go over the 1 gram restriction.

If you have enough of them you can just lose some fraction and still function.

Also it may work out that a lighter, faster probe with a shorter service life could have a greater effective range, if the service life is less sensitive to weight changes than the speed is

Right, that’s a nice way of thinking about it.

And how do you get the data back from these probes? The voyagers have antennas that are close to 4 meters in diameter and ~25-watt radio transmitters. You aren't doing that in a gram, and you aren't powering that in a gram either.

Just go read the starshot proposal. They address all of these issues, some more convincingly than others but they have thought it out in great detail.

In short, it’s a swarm of gram-scale probes and they work together to transmit.

The claim was that it would always be the furthest man made object in the universe. Nothing about it being useful or scientific.

If its not useful, it's not going to be launched and accelerated that long.

People do things for shits and giggles all the time. SpaceX literally launched a model Tesla for absolutely no reason other than advertising both themselves and their sister company.

Doubly so if they can now become “the furthest man made object”. That’s massive free marketing.

It may also be exponentially easier to do so in the future, lowering the expenditure needed to make it happen.

It might not be reasonable right now, but, once again, the bar was set at always. That is an exceptionally high bar with very little reasoning behind it.

They absolutely had way more of a reason than no reason. Za reason for the Tesla launch was that it was the first falcon 9 heavy launch, and no company was willing to gamble that large of a payload on a untested rocket. So they made the best of it with a PR stunt.

They literally could have sent up anything and it certainly wasn’t useful, which was GP’s only criteria for being launched.

>scientific return

that comes after 'someone out there' misinterprets our super fast gram probes as weaponry and conquers our world for the sake of their own spacecraft safety.

it's ingenious really, let's antagonize a greater power into wormhole-bridge hopping over here so we can reverse engineer their tech.

/s , hopefully.

If they are so much as inconvenienced by our probes, they are not a greater power but bumbling roboticists like us.

1 gram at an appreciable amount of c is about as much energy as a nuke. Getting hit by a swarm of these while on a Sunday drive would fuck you up, no matter how powerful you are.

The real reason there isn’t a moon colony? Person gets fired and loses their shit, starts tossing 1-2 km sized rocks down the gravity well and … we all die.

Throwing shit in space is a sure fire way to piss off any species.

It would take an insane amount of energy to throw that rock.

But you only need one. Maybe two for good measure

Same with a nuke or an engineered pathogen. Throwing rocks from the Moon is less practical though, people would see you setting up the universe's biggest launch pad or railgun for years. It would be the least stealthy, most telegraphed apocalypse possible.

It only takes a 50-meter (radius) rock to destroy a city, a 240-meter rock to destroy an entire region, and a 4 km rock to destroy the planet.

So, I guess it depends on what you want to accomplish, whether they see it coming or not.

"Only". Those are huge! Especially when you consider the city you have to build around them to launch the damn things.

The required delta-v isn't all that much from the moon, and it's more about the mass and speed than the actual shape of the rock.

To throw a 100 meter rock that would wipe out NY city (and then some), we could do that with modern technology... assuming the rocket never had to slow down.

If you have enough of them, you get data from Alpha Centauri within a human (natural) lifetime. Plus the bragging rights, I guess, Starshot is after all a private endeavour.

I don't see a date announced for launch, and I see a lot of technology that needs to be invented for this to be feasible. How likely is it to happen within the next 10 years?

I'm just thinking about my old roommate, a space science postdoc, who told me about all these cool propulsion projects that sounded very feasible. That was—sheesh—20 years ago, and I keep waiting for any of them to be real.

It's just a question of funding. There's nothing that's needed to accelerate small enough probe on an escape trajectory at a few hundred km/s except plain old chemical rockets with enough stages. If we can accelerate a >500 kg probe to 20 km/s, we can certainly use an extra stage with 400 kg of propellant to boost a 1 kg probe to much higher velocities.

And nobody talked about the next ten years. The GP said "fifty years", which is way too long a time span to have any certainty whatsoever as to what will happen. GP's assertion was 100% ludicrously overconfident.

Just a note: I responded directly to a comment that said it could be built with today's tech, let alone 10, 20, or 50 years.

Ah, yes, it was my own comment :D Sorry for the confusion. What I meant was that bog-standard chemical rockets work just fine for ~100 km/s if the payload mass is low enough and you use enough stages.

But note that "within a decade" I meant "within a decade from launch".

> There is 0 chance anything will catch up to it in the next 50 years, and probably for several hundred more years after that, if ever.

That is a bit pessimistic. There is this paper [1] by JPL and Nasa folks discussing the possibilites of sun-diving solar small satelites. They think that speeds of around 7 AU/year are possible. Voyager 1 is escaping the solar system at 3.6 AU/year. With those speeds catching up to Voyager 1 withing 50 year would be doable. Realistically since we are not quite ready to launch it just yet it is more likely we would miss that 50 year window but I feel better about our odds in the window beyond 50 but within “several hundred years”.

1: https://arxiv.org/pdf/2303.14917

Don’t forget that sun-diving at high warp speed also gives us more time.

https://en.wikipedia.org/wiki/Star_Trek_IV:_The_Voyage_Home

But if we are warp capable, then we can definitely catch up with V’Ger, I mean Voyager.

https://en.wikipedia.org/wiki/V%27Ger

https://en.wikipedia.org/wiki/Star_Trek:_The_Motion_Picture

Voyager 1 only gravity boosted at Jupiter and Saturn. That's not a particularly special alignment. Doing the same thing doesn't need a "grand tour" alignment, which happens every almost-two hundred years by the way.

Also it got most of its speed from Jupiter, and we can do a gravity assist with Jupiter any year.

And check out this plan for a double Jupiter gravity assist. https://www.hou.usra.edu/meetings/lpsc2020/eposter/1110.pdf

Is the assist multiplicative or additive?

Additive.

nothing in this universe has 0 chance.

Plugging a USB cable into the back of a monitor on the first try without looking is as close as we've ever come to zero chance.

Third try always

The odds do not increase all that much with looking either.

USB-C fixes this, only to replace the problem of orientation with the greater specter of alternate mode support, or lack thereof. This is why we can’t have nice things.

The real life USB C experience has replaced the "which side is up" problem with the "is this cheaply made garbage electronic device going to charge at all with my $80 MacBook USB C charger", which it often does not (and instead requires a USB A to USB C charging cable)

I have also seen these issues and always wondered why this happened. There seems to be an issue with the tolerances of USB C compared to A that make C more susceptible to damage and also dirt and dust.

The main issue seems to be lack of resistors in some devices, which leads to USB C not seeing the device to be charged as such, as it isn't negotiating the USB-PD part. USB A doesn’t officially implement a power delivery negotiation spec, it’s just always on at the charger end, with more amps possibly being negotiated if I’m reading properly.

People seem to be able to resolve this issue with a daisy chain. Devices that usually only work with A to C cables might be able to use a C charger connected to a C to A (female) cord or A to C adapter, which is then connected with a standard A to C cable to the device to be charged.

It’s probably easier to keep a USB A charger and A to C cable, but hopefully this helps put your mind at ease that there is a rational explanation.

https://acroname.com/blog/why-usb-c-connections-sometimes-do...

https://plugable.com/blogs/news/understanding-usb-c-charging...

https://en.wikipedia.org/wiki/USB-C

The Reddit post below actually explains how to work around the problem as I mentioned above:

https://www.reddit.com/r/UsbCHardware/comments/w1ismo/how_co...

oh im totally aware of there being a reason, it's just massively annoying because i deliberately seek out USB C stuff (which is thankfully becomming the default) and then frequently having to return it because the whole point for me is having a single charging solution and not 4 of them

USB-C only mostly fixes the what side is up problem. I've had devices that degraded to only working with the right side up. Usually from pocket fluff accumulation that can be cleaned out, but still.

If I understand the spec properly, the cable isn’t truly symmetrical internally and relies on switching to determine which pins are used for which function. It all seems needlessly complicated to my reading, and it seems like Apple’s Lightning connector is superior in these respects, although I don’t know if it would be capable of performing at USB C’s USB3/4 speeds and implement all its modes, but we're unlikely to get a new connector standard anytime soon, possibly a few USB generations at least. By then, the use case for USB is likely to be much different also, so different design choices are likely to be made to respond to future market conditions that are difficult for me to predict, but I hypothesize that by then ad hoc wireless power delivery and data transfer will be much more mature.

Another unfortunate blunder resulting from the complicated design is that usb C female to usb A male adapters are unsafe and prohibited by the usb C spec (because they can be used to make unsafe connectors)

You still see those adapters frequently because this stupid decision would hobble usb C adoption (since it would prevent you from making a usb C peripheral with backwards compatibility for usb A using an adapter) so manufacturers have largely ignored that part of the spec

I’m somehow failing to understand the use case you’ve described and I don’t think it’s your fault. I’ve seen devices with female USB C ports, and they’re perfectly backward compatible - you either use a C to C cable or A to C cable depending on what is on the other end.

I sometimes see nonstandard A to A cables, however, possibly for the same reasons you’ve mentioned above, but I think it’s usually a cost-saving measure and perhaps easier to implement type A female connectors rather than mini/micro type B, but I have no experience with designing devices, only operating and repairing them.

What is your experience with devices that are backwards compatible with an adapter like you describe? Do you have an example of one, because I can’t think of any, not that I doubt they exist.

If you have a usb NIC, chances are it has a male plug so it can connect directly to a computer without an extra cable.

If it has usb A male, it can connect to a large number of computers, but nothing from Apple recently. If it has a usb c male, it can connect to recent Apple computers but has limited ports on other computers and can't connect to older computers.

If it has a usb-c and a usb-a male to usb-c female dongle (often attached to the little bit of cable between the device and the plug), then it will work with everything.

If you clip off the dongle, then you can use it to connect usb c male devices to usb-a female ports in lots of useful applications. It violates the spec, but it's super handy. If you have a usb a male to usb c male cable, you can use the forbidden dongle and the allowed cable to make a forbidden usb a male to usb a male cable which is probably not useful for much.

I appreciate your example of a USB NIC, as I am familiar with both USB A and USB C versions of those. I was specifically envisioning devices with female ports, but out of convenience and convention, most peripherals have a built-in/permanment male-terminated cord. Can you think of any examples with a female port?

One of my favorite YouTube creators, DIY Perks, made a video about converting USB connectors to USB C which is very well done, as is their usual standard of quality.

https://www.youtube.com/watch?v=V-vFtiDYiIw

Powered usb hubs tend to have a female port for inbound rather than a captive cable. Printers and scanners often have a female port (often usb-B). Some external hard drive docks have female ports, all of mine predate usb-c, so I don't know if the common port has changed.

Things expecting to be charged/powered by usb tend to have female ports --- phones, rechargable video game controllers, espX boards, that sort of thing.

I conceptually equate female ports with host mode devices, but that’s always an assumption that holds true. USB is kind of a mess and I’m glad it all works as well as it does, to be honest, but it’s not without its quirks and rough edges.

Ah my bad, I guess the problem isn't quite as ubiquitous as I thought.

The use case I mean is the same as the other commenter mentioned, devices with a captive male USB c cable, the notable example for me personally is docking hubs, two of the three brands my work recently procured have got one of the other IT teams in a tizzy, because the procuring team didn't realize that the included c to a adapters were problematic. For one brand the adapter was permanently attached to the cable too, I wonder if as a mitigation for the chance of misuse?

But the general case is devices with an integrated male USB c cable

Exception that proves the rule! Plugging USB-A on the first try equals excalibur out of the stone. Our Arthur is out there, somewhere.

Somehow, it always works on the third try.

Well, you’re probably right since it seems like the US govt is foaming at the mouth to start ww3 with both Russia and China.

I will bet you literally all the money ever printed that we don’t.

That’s not how betting works. How much would you really bet, your own real money? For example, I’m totally ready to take the bet at merely 1:1000 odds. In 30 years, let’s say, I’d owe you a $100 if a probe hasn’t broken V1’s distance record, and you’d owe me a hundred grand if we have. In today’s dollars. Should be a no-brainer if you really think it’s impossible.

It does't work to get fair odds (estimated value 1) when the gains are a nice dinner downtown and a loss might be financial servitude.

One thing's for sure, $100,000 in today's dollars won't buy you dinner by the time the bet's resolved.

Doesn't the phrase "today's dollars" imply the practical value will stay the same?

If we're going to worry about inflation, we might as well worry about the climate burning up our planet.

Maybe I'm being overly pessimistic, but the next ~100 years we'll be bothered trying to have enough food and water and killing ~80% (or more) of humans of the planet who want our food, water, and shelter from the extreme weather that we won't be sending anything to chase the Voyagers...

Nah. This is basically the worst of the worst IPCC scenarios, highly unlikely but for some reason the preferred ones by journalists and self-serving politicians as well as big green industry grifters.

Back of the napkin math shows it to be the most likely, especially with some of the more recent discoveries in regards to water evaporation and co2 emissions.

IPCC is sorely outdated by this point.

https://www.youtube.com/watch?v=4S9sDyooxf4

TL;DW (poorly): Even IPCC scientists are sort of refusing to believe pessimistic data.

I hope we are getting to the point were rationality will prevail again. We need a balanced view of things, having only -1 on this comment of min here, on HN, which by nature is a climate doomer central fills me with hope.

The only solution is technological advancement.

If humanity doesn’t rise to the challenge (degrowth) this could happen.

Fortunately there are smart people all over the world solving problems everyday and that is likely to continue.

As the ancient South Park meme says...

1. Technological advancement

2. ?

3. Climate change fixed

As I said either advance or die. Reducing energy consumption isn’t an option, it will continue to grow unbound.

I could take the bet at 1:100 odds too.

And that’s not how long term bookmaking works, as you’ve proposed a wager where I am guaranteed to lose at least the time value of my money on either outcome, and I’m extremely confident I’d lose exactly and only that. But I’ll happily put down $100 in today’s money if a win in 30 years returns a 10% profit over inflation, on the conditions that the probe must be launched from the Earth’s surface after the book is made, that it must overtake Voyager 1’s then distance inside 30 years, and that it must be actively transmitting at least one piece of meaningful local-condition scientific data back under its own power (for validation of ranging purposes, at least) at that time.

I will bet you 10 times more to the contrary, literally, absolutely :D

On our way to where exactly?

One target would be about 500AU out, where you can use the sun as a gravitational lens.

https://en.m.wikipedia.org/wiki/FOCAL_(spacecraft)

"Always" is a pretty big leap (I hope).

Yes, but it will always be like that

That’s the major problem with generation ships. Unless you have a propulsion lab and scientists on the ship, earth will just keep making faster ships and when you arrive at your destination you may discover it has been inhabited for generations by people who left a hundred years after you did.

The power of procrastination is great.

I mentioned this point on a HN post a few months ago and someone said that the Voyager was launched at a very beneficial time, leveraging some gravitational pull of some celestial body, so it’s unlikely we can just make a faster ship and catch up/surpass it.

Is there any reason that a new generation of ships couldn't leverage the same (or similar, if not better) gravitational pulls that benefited Voyager?

The "Grand Tour" alignment that Voyagers were initially intended to take advantage of only happens once every 175 years (although if the goal is just max speed I don't know if favorable conditions happen more often than that)

That’s just a standard chemical rocket for the initial push and then a few gravity assists right?

Couldn’t an ion engine with a nuclear reactor providing the electricity accelerate more over that period? I’m genuinely curious, I don’t know the answer.

Even an ion engine needs fuel. We shot out Voyager 1 in 1977. It has traversed 47 years of distance.

There has been the talk of solar sails as well, but gravity assist propulsion is already so much easier to achieve for satellites.

If I thought 17 km/s was even half of the fastest we would ever go, I’d have to give up a lot of dreams for the future. Since I’m not prepared to do so I will stick out my proverbial tongue at this assertion.

This gets really interesting, and weird, if we're ever able to start making ships capable of approaching relativistic rates. You could arrive at the destination after 500 years, only to discover that humans colonized it 50,000 years ago.

For those who may not know, the speed of light isn't really a speed limit per se. If you have a button that gives you an acceleration of 1km/s, nothing stops you from hitting it 300,000 times in a row (with the speed of light being ~300,000km/s), or even a billion. Instead the entire universe begins to distort with distances becoming literally physically closer, and with rate of time itself also changing (length contraction + time dilation are the terms).

It has the interesting implication that if we could ever create a ship that "just" accelerates at 1g, you could travel essentially anywhere in the universe, even if it's billions of light years away, in a single human lifespan! [1] So for instance the distance to the closest galaxy, Canis Major, is about 25,000 light years. You could get there in our 1g ship in less than 20 years. Of course, 25,000 years would genuinely have passed in the interim, so you get all sorts of fun paradoxes and oddities. And the oddities are exponential, so you could travel a billion light years in 40 years.

And this isn't just hypothetical or whatever. Time dilation plays a major role in many things, like particle accelerators. Unstable emergent particles end up 'living' for far longer than they should thanks to the fact they're moving at near light speed relative to us, which means that time is [relatively] passing for it more slowly than for us.

[1] - http://convertalot.com/relativistic_star_ship_calculator.htm...

> would genuinely have passed

I think the whole point of this whole relativity thing is that there are no genuine years :P

You are wrong in the sense time dilation happen in different observer … it is nothing to do with one object. Your time remained as your length to you.

Light speed is the limit. You cannot exceed it and you reach it time stop to you … but still you move on in the speed of light.

Another issue you have thought of is the real space “dilution” or that bloody constant Einstein mistake originally. The so called dark energy describe it. We are not sure as it depends upon the model. But it is very unlikely you can reach everywhere you like unless the universe loop around itself (so like on a Sphere you can cover the whole surface of the sphere if you travel with unlimited time … except it expand as we think it is and you cannot).

One possibility though is the universe contract. Then no need to travel la. The whole universe collapse on you.

What happen when we reach the point our laws of physics as we know it no longer held … no human knows. May be …

Let there be light. As God in bible does not make this world out of nothing it seems. Or if you not God person then the empty vacuum field has possible enough to produce the universe (and destroyed it in 10^-32 second.

Anyway all amazing stuff. Just as a hacker really really want an emulator and look around this human artifice that is our gift to the universe. (Just hope the tv serial of hitter in Germany olpymic does not hurt our images).

"Pushing Ice" by Alastair Reynolds is a great sci-fi novel that explores some of these ideas, if anyone's interested. Highly recommended!

Thanks, going to check it out. Sounds like my kind of thing.

> And this isn't just hypothetical or whatever.

I always find it fascinating to think that this manifests in GPS that everyone casually uses: the timings have to account for the fact that time on the constellation’s satellites passes a little bit faster than on earth and corrected to get accurate positioning on earth.

The nuclear launched manhole cover is likely further

I think that burned up before exiting our atmosphere.

I'm not sure about that. At its launch speed (lower limit 66 km/s) it would have taken under a second to get to where the atmosphere is no longer thick enough.. would that have been enough time to vaporize it?

It's the other way around. Regardless of speed, it has the same number of particles to displace. At high speed these particles you're hitting are like hitting a concrete wall. The faster you go, the worse it is, and the less time you have to cool down the heat you're generating.

Which one is that?

Reply on news.ycombinator.com