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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

#331

Post by thenthenthen »

ianburrell wrote: post #186
pseudocomposer wrote: post #49

Earlier quoted context omitted.

This is a silly counterexample - why would we launch them that far apart? It’s a terrible idea for multiple reasons. We’d want them close together, with some redundancy as well, in case of failures. What dish size would be required for a “cylindrical/tubular mesh” of probes, say, 1AU apart (ie Earth-Sun distance)? I’m pretty sure that would be manageable, but open to being wrong. (For reference, Voyager 1 is 169AU fr…

Light year is 63,241 AU. That means tens of thousands of relays. It would super expensive and super unreliable. The other problem is that achievable speeds are super slow, Voyager is 25,000 years per light year which means that would wait 100,000 years for relays to Alpha Centauri to be possible. Much easier just to send probe with large antenna or laser, and make a large antenna at Earth.

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

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

#332

Post by chmod775 »

tpurves wrote: post #58
glenstein wrote: post #30

Not that we would literally do this with Voyager, but it makes me wonder at the potential utility of a string of probes, one sent every couple of [insert correct time interval, decades, centuries?], to effectively create a communication relay stretching out into deep space somewhere. My understanding with the Voyagers 1 and 2 is (a) they will run out of power before they would ever get far enough to benefit from a re…

What you are describing has been proposed before, for example within context of projects like Breakthrough Starshot. In that the case the idea is to launch thousands of probes, each weighing only a few grams or less, and accelerating them to an appreciable fraction of the speed of light using solar sails and (powerful) earth-based lasers. The probes could reach alpha centauri within 20-30 years. There seems to be som…

What these proposals like to forget (even if addressing everything else) is that you need to slow down once you arrive if you want to have any time at all for useful observation once you reach your destination.

What's the point of reaching alpha centauri in 30 years if you're gonna zip past everything interesting in seconds? Will the sensors we can cram on tiny probes even be able to capture useful data at all under these conditions?

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

#333

Post by burnt-resistor »

godshatter wrote: post #63
elashri wrote: post #31

Wow, this gives a reflection about our future. The nearest potentially habitable planet known is Proxima Centauri b, which orbits the red dwarf star Proxima Centauri about 4 light‑years from Earth (at least it is in a habitable zone of its star) [1]. So we don't have a choice actually except protecting and make sure our planet survives. That's regardless if it really would be able to support life as we know or not (p…

In my opinion, if we really want a presence off of earth we'd be better off building larger and larger space habitats and bootstrapping a mining industry in space.

Yep, so long as there are clear, positive incentives or it could become a corrupt, expensive boondoggle depriving ordinary people on Earth. And Mars ain't it except underground.

Nit: "earth" is dirt, but "Earth" is always capitalized when referring to the celestial body we inhabit.

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

#334

Post by vintermann »

anonzzzies wrote: post #283
threethirtytwo wrote: post #88

Earlier quoted context omitted.

No one likes to think this but it’s very possible voyager is the farthest humanity will go. In fact realistically speaking it is the far more likeliest possibility.

1. Get to AGI 2. Optimise for energy efficiency 3. Shoot billions of AGIs into space a year ... Be responsible for the very longterm torture of billions of intelligent lifeforms who are forced to drift through boring space for 1000s of years.

If you make it, you can make it like it.

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

#335

Post by Spare_account »

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).

For anyone interested, this is approximately the wait/walk dilemma, specifically the interstellar travel subset: https://en.wikipedia.org/wiki/Wait/walk_dilemma#Interstellar...

I was listening to an old edition of the Fraser Cain weekly question/answer podcast earlier where he described this exact thing. I think he said that someone has run the numbers in the context of human survivable travel to nearby stars and on how long we should wait and the conclusion was that we should wait about 600 years.

Any craft for human transport to a nearby star system that we launch within the next 600 years will probably be overtaken before arrival at the target star system by ships launched after them.

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

#337

Post by noduerme »

chmod775 wrote: post #332
tpurves wrote: post #58

Earlier quoted context omitted.

What you are describing has been proposed before, for example within context of projects like Breakthrough Starshot. In that the case the idea is to launch thousands of probes, each weighing only a few grams or less, and accelerating them to an appreciable fraction of the speed of light using solar sails and (powerful) earth-based lasers. The probes could reach alpha centauri within 20-30 years. There seems to be som…

What these proposals like to forget (even if addressing everything else) is that you need to slow down once you arrive if you want to have any time at all for useful observation once you reach your destination. What's the point of reaching alpha centauri in 30 years if you're gonna zip past everything interesting in seconds? Will the sensors we can cram on tiny probes even be able to capture useful data at all under…

Could the probe just fire off some mass when it got there?

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

#338

Post by viralpraxis »

threethirtytwo wrote: post #88
glenstein wrote: post #30

Not that we would literally do this with Voyager, but it makes me wonder at the potential utility of a string of probes, one sent every couple of [insert correct time interval, decades, centuries?], to effectively create a communication relay stretching out into deep space somewhere. My understanding with the Voyagers 1 and 2 is (a) they will run out of power before they would ever get far enough to benefit from a re…

No one likes to think this but it’s very possible voyager is the farthest humanity will go. In fact realistically speaking it is the far more likeliest possibility.

I was always wondering if there’s some sort of limitation in science. Just like in some games you can’t fly according to the rules (science), so there’s just no way to do that without cheating. What if e.g. in 5k years we will reach the limit? Basically like after playing a couple of months in minecraft the only thing you can do is to expand

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

#339

Post by Fargren »

noduerme wrote: post #337
chmod775 wrote: post #332

Earlier quoted context omitted.

What these proposals like to forget (even if addressing everything else) is that you need to slow down once you arrive if you want to have any time at all for useful observation once you reach your destination. What's the point of reaching alpha centauri in 30 years if you're gonna zip past everything interesting in seconds? Will the sensors we can cram on tiny probes even be able to capture useful data at all under…

Could the probe just fire off some mass when it got there?

Any mass that it fires would have a starting velocity equal to that of the probe, and would need to be accelerated an equal velocity in the opposite direction. It would be a smaller mass, so it would require less fuel than decelerating the whole probe; but it's still a hard problem.

Be careful with the word "just". It often makes something hard sound simple.

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