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Voyager 1 is about to reach one light-day from Earth

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Re: Voyager 1 is about to reach one light-day from Earth

#401

Post by adrianN »

SJC_Hacker wrote: post #390
adrianN wrote: post #382

Earlier quoted context omitted.

Accelerating something macroscopic to hundreds or thousands of km/s (i.e. the speeds you can achieve with nuclear pulse propulsion) on a ramp that fits on the moon seems quite difficult to me.

Mass drivers don't need to be a linear ramp, portions can be circular It would work better for smaller, unmanned craft, especially when you consider g force limitations NPP is only theoretical, and still has major problems such as finding a material that can withstand a nuclear detonation at point blank range. Mass drivers have been proven to work, albeit at a smaller scale

Pulse propulsion has also been demonstrated at small scales, so I guess the technology is at similar scales of practicality. G forces scale with the square of the velocity, I think.

Re: Voyager 1 is about to reach one light-day from Earth

#402

Post by busssard »

teleforce wrote: post #377
leo_e wrote: post #355

It really puts our current definition of "latency" into a painful perspective. We have a machine running on 1970s hardware, a light-day away, that arguably maintains a more reliable command-response loop relative to its constraints than many modern microservices sitting in the same availability zone. It’s a testament to engineering when "performance" meant physics and strict resource budgeting, not just throwing more…

> not just throwing more vCPUs at an unoptimized Python loop. I've got the strong feeling that most of the Python frameworks, stacks and codes in operation of our generation will be the technical debts of the future computer world. The fact that Python was meant primarily as both learning language (ABC legacy) and glue language (akin of scripting but not for building) make the Python based systems and solutions the d…

i thought everything is being rewritten in rust nowadays?

Re: Voyager 1 is about to reach one light-day from Earth

#403

Post by onethought »

mindslight wrote: post #102
onethought wrote: post #46

Earlier quoted context omitted.

Or we learn how to make uninhabitable planets habitable. Would also help us “save” this one. (Funny how we say “save the planet” when we really mean “save people/complex life”).

Given that there is very little interest in developing commons here on earth (especially new types of commons from whole cloth), the shape that "making uninhabitable planets habitable" would likely take is that of living in bubbles rather than some kind of broad-scale terraforming. This would intrinsically shape society towards top-down authoritarian control, rather than allowing for distributed individual liberty. I…

Some handwavy logic there, both on why bubbles instead of terraforming and also why authoritarian control given bubbles.

Re: Voyager 1 is about to reach one light-day from Earth

#404

Post by Sanzig »

SJC_Hacker wrote: post #390
adrianN wrote: post #382

Earlier quoted context omitted.

Accelerating something macroscopic to hundreds or thousands of km/s (i.e. the speeds you can achieve with nuclear pulse propulsion) on a ramp that fits on the moon seems quite difficult to me.

Mass drivers don't need to be a linear ramp, portions can be circular It would work better for smaller, unmanned craft, especially when you consider g force limitations NPP is only theoretical, and still has major problems such as finding a material that can withstand a nuclear detonation at point blank range. Mass drivers have been proven to work, albeit at a smaller scale

IIRC, Dyson proposed using a thin layer of oil on the surface of the pusher plate that would get vaporized with each shot, but would prevent the plate from ablating away. This effect was discovered by accident during nuclear testing when oil contamination on metal surfaces in close proximity to the explosion would protect them.

Of course, depending on how much oil you consume for each shot, you will degrade your effective specific impulse - I'm not sure by how much though.

The other issue which you can't really get around is thermal, that plate is going to get hot so you'll have to give it time to radiate heat away between shots. This may be less of a concern for an interstellar Orion since the travel times are so long anyway, low average thrust may not matter too much.

Re: Voyager 1 is about to reach one light-day from Earth

#405

Post by glenstein »

chucksmash wrote: post #362
thenthenthen wrote: post #331

Earlier quoted context omitted.

Starlink has 10k satellites as per this Month. 60k doesnt seem unreasonable?

Starlink has a use case. At Voyager 1 speeds, it'll take 70,000 years for a probe to reach Proxima Centauri. So you'd just be launching a probe a year for the next 70,000 years to create a temporary chain on a course to fly by one particular star. And for what purpose? Okay, in 70,000 years, if everything works out as expected, we have a chain of probes on a course to fly by Proxima Centauri. What problem does that s…

The purpose is (1) deep space observation of our most plausible colonization target outside of the solar system and (2) ramping up a fault tolerant maintenance corridor for generation ships or whatever best alternative paradigm takes the place of generation ships.

What's weird here is that a lot of the criticisms just zoom in on one of the logistical steps and randomly assume it would be executed the worst way possible. I honestly don't know what distance threshold counts as necessary redundancy in this case, but if it's not 1AU (which seems too small imo), then substitute the steelmanned optimal distance and criticize that.

Suppose instead of one-time flybys it's the first half of a long trip to and from, gravity assisted by the major celestial objects of the Alpha Centauri system. I don't want to suggest that it's currently anything like a final draft, but there's ways to steelman these proposals instead of going for the low hanging fruit.

Being a philosophy major didn't convey many practical benefits to me, but one thing I did gain from it was never forgetting the importance of charitable interpretation and steelmanning.

Re: Voyager 1 is about to reach one light-day from Earth

#406

Post by Tepix »

trhway wrote: post #299
Tepix wrote: post #64

Earlier quoted context omitted.

Indeed. I think the main reason to send thousands of probes is increasing the odds that they will survive the trip and also be in the right position to gather usable data to transmit back. Also once you have created the infrastructure of hundreds or thousands of very powerful lasers to accelerate the tiny probes to incredibel speeds, sending many probes instead of a few doesn't add much to the cost anyway.

Sun as a focus lens. "Just" 500 AU. The Voyager can be overtaken in several years if we to launch today a probe with nuclear reactor powered ionic thruster - all the existing today tech - which can get to 100-200km/s in 2-3 stages (and if we stretch the technology a bit into tomorrow, we can get 10x that).

From what I understand a Solar lens telescope could only point to a single destination.

Btw 500 AU is 69 light hours.

Re: Voyager 1 is about to reach one light-day from Earth

#407

Post by swores »

shagie wrote: post #147
swores wrote: post #134

Earlier quoted context omitted.

You’ve given numbers for how fast New Horizons launched, and for how fast Voyager 1 got thanks to the 1-in-175-years boost, but is there an easy way to actually compare them? IE either what speed Voyager 1 launched at excluding the gravity assists, or what speed New Horizons would have reached if it were launched 175 years after Voyager 1 (to take advantage of the same gravity assists)?

Not easily. The tricky part is also in the relative numbers. The Voyager 1 data (and New Horizons data now) is in heliocentric velocity. The bit with NH being the fastest was with Earth centric velocity. Another part in this is the "the probes are slowing down over time" - and you can see that with the Voyager 1 data that while the velocity after assist is higher than before, its not a line at slope 0 but rather a cu…

Oops, just realised I forgot to reply. Hopefully you're signed up to get emailed reply notifications, to see me say: thanks for this interesting comment!

Re: Voyager 1 is about to reach one light-day from Earth

#408

Post by jacobgkau »

threethirtytwo wrote: post #378
anigbrowl wrote: post #314

Earlier quoted context omitted.

This is reflexive pessimism with no substance. You're not articulating a set of particular challenges that need to be navigated/overcome, which could provide a roadmap for a productive discussion; it's just doomposting/demoralization that contributes nothing.

I don't want to introduce 50 tangential branches to argue about with no end in sight. It's not pessimism, it's reality. Think about how unlikely it is. Humanity had one stretch where we reached for the stars and that stretch ended and by sheer luck some crazy guy made it cheap. What happens when he's gone? Will it happen again? Most likely: no. In your lifetime? Even Less likely.

Nobody was talking about only their own lifetime here. Even invoking that is off-topic pessimism ("you're going to die before stuff gets better").

Re: Voyager 1 is about to reach one light-day from Earth

#409

Post by bookofjoe »

chistev wrote: post #142
trenning wrote: post #135

Earlier quoted context omitted.

Próxima Centauri is about 250 million years older than our sun. Makes it not-impossible their earth like planet had advanced entities capable of sending their own voyager towards earth. Possibly it flew by while we were still in our Mesozoic Era and all they saw were dinosaurs.

I love thinking about things like this, but we will never know! Sometimes I close my eyes and imagine I traveled back in time to the days of the Dinosaurs and just observed how the world was back then. But I wonder if I'd be able to survive. The atmosphere, environment, microbes, etc, would be drastically different from what we've evolved to handle. Millions of years ago is a very long time! Edit: Apparently microbes…

You will like this 1952 story by Ray Bradbury:

https://www.astro.sunysb.edu/fwalter/AST389/ASoundofThunder....

Re: Voyager 1 is about to reach one light-day from Earth

#410

Post by mindslight »

onethought wrote: post #403
mindslight wrote: post #102

Earlier quoted context omitted.

Given that there is very little interest in developing commons here on earth (especially new types of commons from whole cloth), the shape that "making uninhabitable planets habitable" would likely take is that of living in bubbles rather than some kind of broad-scale terraforming. This would intrinsically shape society towards top-down authoritarian control, rather than allowing for distributed individual liberty. I…

Some handwavy logic there, both on why bubbles instead of terraforming and also why authoritarian control given bubbles.

It's not "handwavy logic". It called reasoning based on heuristics developed from many observations (ie wisdom).

From what I've seen here now on Earth, large scale coordination of projects where the benefits end up mostly diffuse is effectively impossible, especially in the modern environment. Thus private ownership of scaled back projects, organized by corporate authoritarianism as we see for most businesses here now on earth.

Could we possibly have an Earth country/company developing open-space terraforming, investing with the idea they will develop owned colonies, but then a popular revolt throws off the authoritarian control and institutes distributed rights (ala the American Revolution) ? Sure, that's possible. But that also just seems unlikely to be given modern information systems facilitating large scale surveillance, sentiment control, and promoting singular authoritarian perspectives. Like we're currently in the process of rolling back those hard-won distributed rights here now on Earth ("slowly at first, then all at once").

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