Wrote about the Voyager probes two days ago in my blog -
The two Voyager spacecraft are the greatest love letters humanity has ever sent into the void.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
When I read stats like this I realize how stuck in this solar system we are. I wonder if billionaires would care for the planet more if they knew that Earth is honestly just it for humans, for maybe forever.
An uncrewed payload of 30 tons to some far off distance over the course of 100 years is the answer to how it's not really possible to colonize space?
No paper plan dependent on "pulsed nuclear propulsion" ie blowing up nukes under your ass, is anything other than pop scifi.
"Pulsed nuclear propulsion" as Project Orion described itself is an insane pie in the sky imagined idea, and itself might not be possible, and yet Daedalus and Longshot both expect orders of magnitude improvements over that?
Oh, and the hundreds of tons of propellant for this magic drive has to be mined from jupiter or something.
You people should stop demonizing billionaires. You're the ones burning the fossil fuels, not them. If their wealth way distributed among more people then those people would spend it damaging the environment which is what people generally do with their money anyway.
The way I see it, it takes a very selfish person to be a billionaire in the first place— one that not only doesn't care about people today, but also doesn't care about future generations of humans, let alone other living beings.
Any billionaire pointing at space exploration as humanity's salvation is, IMO, either really just craving the attention and glory of conquest (much like Caesar, Napoleon, Alexander, etc) or seeking the conditions of the age of exploration (XV to XIX centuries), when companies were as powerful as governments and expansionism was unfettered.
At Voyager 1's velocity, it would take ~456 million years to reach the heart of the Milky Way (Sagittarius A*), some ~26,000 light-years away. That's roughly the same amount of time that has passed since the Ordovician–Silurian extinction, when volcanic eruptions released enough carbon dioxide to heat up the planet and deoxygenate the oceans, resulting in the asphyxiation of aquatic species (about 85% of all life was snuffed out). The oceans remained deoxygenated for more than three million years.
"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean you may think it's a long way down the road to the chemist, but that's just peanuts to space."
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 relay and (b) they benefited from gravity slingshots due to planetary alignments that happen only once every 175 years.
So building on the Voyager probes is a no-go. But probes sent toward Alpha Centauri that relay signals? Toward the center of the Milky Way? Toward Andromeda? Yes it would take time scales far beyond human lifetimes to build out anything useful, and even at the "closest" scales it's a multi year round trip for information but I think Voyager, among other things, was meant to test our imaginations, our sense of possible and one thing they seem to naturally imply is the possibility of long distance probe relays.
Edit: As others rightly note, the probes would have to communicate with lasers, not with the 1970s radio engineering that powered Voyagers 1 and 2.
My intuition is that the extra mass for the receivers would be a large negative in terms of travel time (1/sqrt(m) penalty assuming you can give each probe fixed kinetic energy).
Plus keeping a probe as active part of a relay is a major power drain, since it will have to be active for a substantial percentage of the whole multi-decade journey and there's basically no accessible energy in interstellar space.
Then again, it's still far from clear to me that sending any signal from a probe only a few grams in size can be received at Earth with any plausible receiver, lasers or not.
This is a link budget problem. A probe has to have a certain transmit power, receive sensitivity, physical size, fuel for orientation, etc. So you have to come up with the optimums there were it makes sense at all which isn't easy, especially compared to having one big station near earth that communicates point to point with the deep space whatever.
It might just have to be much too big to be worth it in the next n centuries.
If humans settle Mars it'll probably make sense to build one there for marginal improvement and better coverage with the different orbits of Earth and Mars.
Could a probe return data by semaphore? Wave a flag that blocks the light of Alpha Centauri as seen from a telescope off to the side of the sun, say at the distance of Neptune's orbit. It should be possible to hide Alpha Centauri behind a relatively small semaphore until the probe gets fairly close.
I think only the Grand Tour program was possible every 175 years:
From Wikipedia [1]:
"that an alignment of Jupiter, Saturn, Uranus, and Neptune that would occur in the late 1970s would enable a single spacecraft to visit all of the outer planets by using gravity assists."
Gravity assists with more than one planet are more frequent. Cassini-Huygens [2] as example had five (Venus, Venus, Earth, Jupiter, Saturn)
I would suspect when the goal ist only to leave the solar system as fast as possible (and don't reach a specific planet) they are much more often.
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 (probably not).
Proxima flares and bathes Proxima Centauri b in radiation when it does, so it seems unlikely to be particularly habitable. But it's still tantalising...
Note that a journey to a star a 100 light years away where you accelerate and decelerate with a constant 1 g for each half of the journey only takes 9 years of subjective time for the traveller (hence the twin paradox). To Proxima Centauri (4.24 ly) the gain isn’t as dramatic, it would take 3.5 years of subjective time.
Of course, we aren’t anywhere near having the technology for that, and there may not be any suitable planets in that vicinity, but it also doesn’t seem completely impossible.
Once we develop more efficient propulsion (fission, fusion, light sails, etc.), would you like for someone to catch the Voyagers and bring them back into a museum? I myself am not sure. (Perhaps a "live museum" instead, keep them on their trajectories, but surround with a big space habitat with visitor center and whatnot.)
Now the question is, what time is it in voyager 1? With time dilation, the "now" on Voyager is out of sync with our now. I was watching star wars recently and when Han Solo casually say "we should be in Alderaan at 0200 hours", I paused for a second. What does that even mean [0]? Traveling through space is challenging today, but after we figure that out, we will have to face the problem of time keeping across the galaxy.
Here is a funny thought experiment - the distance from Voyager to Earth varies by approximately 16 light minutes throughout the year. Why? Because it takes ~8 minutes for light to go from the Sun to the Earth, so presuming the Voyager is roughly planar with the Sun/Earth (I'm just assuming yes), that gives a variance of ~16 minutes depending on where the earth is on its orbit.
Now I'm presuming they aren't using the actual Earth position, but rather an average Earth position (which is basically just the Sun's position). Since Voyager is ~30 light minutes away from being 1 light-day away, that means this ~16 minute change can affect our 1 light-day mark by up to ~6 months!
Trump will turn this into "American spaceships, the best in the world, world class probes, now light years away from Earth to find who knows what treasures lie there."
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[ 3.1 ms ] story [ 93.6 ms ] threadhttps://news.ycombinator.com/item?id=46046260
Headline is also misleading. It will do so in November 2026, about a year from now.
Voyager 2 actually launched first, on August 20, 1977, followed by Voyager 1 on September 5, 1977. Because Voyager 1 was on a faster, shorter trajectory (it used a rare alignment to slingshot past both Jupiter and Saturn quicker), it overtook its twin and became the farther, faster probe. As of 2025, Voyager 1 is the most distant human-made object ever, more than 24 billion kilometers away, still whispering data home at 160 bits per second.
https://en.wikipedia.org/wiki/Project_Longshot
No paper plan dependent on "pulsed nuclear propulsion" ie blowing up nukes under your ass, is anything other than pop scifi.
"Pulsed nuclear propulsion" as Project Orion described itself is an insane pie in the sky imagined idea, and itself might not be possible, and yet Daedalus and Longshot both expect orders of magnitude improvements over that?
Oh, and the hundreds of tons of propellant for this magic drive has to be mined from jupiter or something.
Any billionaire pointing at space exploration as humanity's salvation is, IMO, either really just craving the attention and glory of conquest (much like Caesar, Napoleon, Alexander, etc) or seeking the conditions of the age of exploration (XV to XIX centuries), when companies were as powerful as governments and expansionism was unfettered.
That means it will reach a light year in approximately the Earth year 19,860.
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 relay and (b) they benefited from gravity slingshots due to planetary alignments that happen only once every 175 years.
So building on the Voyager probes is a no-go. But probes sent toward Alpha Centauri that relay signals? Toward the center of the Milky Way? Toward Andromeda? Yes it would take time scales far beyond human lifetimes to build out anything useful, and even at the "closest" scales it's a multi year round trip for information but I think Voyager, among other things, was meant to test our imaginations, our sense of possible and one thing they seem to naturally imply is the possibility of long distance probe relays.
Edit: As others rightly note, the probes would have to communicate with lasers, not with the 1970s radio engineering that powered Voyagers 1 and 2.
Plus keeping a probe as active part of a relay is a major power drain, since it will have to be active for a substantial percentage of the whole multi-decade journey and there's basically no accessible energy in interstellar space.
Then again, it's still far from clear to me that sending any signal from a probe only a few grams in size can be received at Earth with any plausible receiver, lasers or not.
It might just have to be much too big to be worth it in the next n centuries.
If humans settle Mars it'll probably make sense to build one there for marginal improvement and better coverage with the different orbits of Earth and Mars.
Gravity assists with more than one planet are more frequent. Cassini-Huygens [2] as example had five (Venus, Venus, Earth, Jupiter, Saturn)
I would suspect when the goal ist only to leave the solar system as fast as possible (and don't reach a specific planet) they are much more often.
[1] https://en.wikipedia.org/wiki/Grand_Tour_program [2] https://en.wikipedia.org/wiki/Cassini%E2%80%93Huygens
[1] https://science.nasa.gov/resource/proxima-b-3d-model/
Of course, we aren’t anywhere near having the technology for that, and there may not be any suitable planets in that vicinity, but it also doesn’t seem completely impossible.
[0]: https://idiallo.com/blog/galactic-timekeeping
Now I'm presuming they aren't using the actual Earth position, but rather an average Earth position (which is basically just the Sun's position). Since Voyager is ~30 light minutes away from being 1 light-day away, that means this ~16 minute change can affect our 1 light-day mark by up to ~6 months!
My mind understands the numbers, but can't grasp them.