Voyagers Detect an Increase in the Density of Space Outside the Solar System
sciencealert.com
sciencealert.com
We got treated to an incredibly indepth tour of the facility - including looking into the ruby maser equipment that amplifies the infinitesimally minuscule signal from voyager.
Truly one of the crowning achievements of the 20th century is to have successfully sent these two objects into deep space and keep in contact with them for over four decades!!
For me personally, I think the deep space probes are the finest examples of man's ingenuity. The use of math and physics to plan and plot something like the journey of the Voyager probes across decades, to actually see it in action and working just as predicted is an amazing thing.
But the voyager probes too could ink out of existence, and the signals they're sending back wouldn't expand the map, they would just be hijacked by the simulation to send back whatver the devs wanted it to.
Wouldn't that require the devs to simulate whatever code we put on the probe? Did you just discover an attack vector for hacking the simulation?
Perhaps the Great Silence is simply down to early Black Hat Aliens who've been feeding fictions to all civilisations that develop beyond straight to eye (etc) optical (etc) instruments?
I think the silence is just that: silence. We're it (right now).
Because of gravity, an entire civilization could live as long as we will on earth but on the right planet it could only take them 30 years per hour (like on interstellar where they were gone an hour on the planet, but off-planet 7 years passed.)
They could've started at the same time, but only be 10 years in, while we've transversed millenia.
Or could be exactly the same as how we evolved, except they did it 1 billion years ago, and died out 500 million years ago.
Top 3 contenders though for me for the fermi silence is: 1. Great Filter wins. 2. Time and Distance scales of space, and 3. We're living in a simulation. Aliens weren't part of the plan.
if alien life were out there, I don't think it'd just be content to hide out. I mean, look at our planet and the food chain, EVERY living thing competes for it's place on the food chain, and in the world. Extra-terrestrially I think we'd also compete w/ other races and see expansions.
If we lived 1 billion years, it's almost a certainty that we could colonize ALL of the milky way, and maybe other galaxies. Def. Andromeda since it'll merge with us soon enough.
That said - My point being - even if there is a tenth of a tenth of a tenth of a chance that my speculation is possibly not entirely incorrect, it then becomes of the utmost importance that going forward that we oblige ourselves in having some almost Monasterial-like utterly analogue back up where external input of first principles are wholly questioned; proved as much as possible from outwith the digital realm and then transcribed and stored in flesh, or by hand, or memory and voice. Elsewise, how do we know our ideas have not been interfered with?
What probes are we sending to reach the same heights as Voyager for the next generation of scientists?
https://en.m.wikipedia.org/wiki/Voyager_program#/media/File%...
It's not such a black-and-white deal. The primary mission of the Voyagers was to study the outer planets, which it completed in ~12 years after launch. The studies on Jupiter and Saturn were already finished 5 years after launch.
Yes. The scope/lifetime of the spacecraft was only to explore the outer planets. The scientists and engineers who designed and built it took it upon themselves to ensure it could stay within the budgetary constraints and exceed the mission scope. Everyone interested in Voyager should watch the documentary "The Farthest" - great documentary!
But what a concept though, how can a space-time be denser than any other? I’m not versed in this, maybe it can?
I believe it's expected that they'll need to pretty much turn off all of the instruments in the next 5 years, and after that it can run it's comms a bit longer but nothing else.
Edit: found an FAQ page from JPL about the Voyagers:
https://voyager.jpl.nasa.gov/frequently-asked-questions/
It looks like this year they need to start shutting down instruments more aggressively, expect to be able to run at least once instrument until 2025, and then there's a possibility of the voyagers staying contactable until 2036 with no instruments running.
To see one application of this information, look for discussions of the "Pioneer Anomaly". That particular effect is now understood, but had it held up to detailed systematic-effect analysis, it would have affected our understanding of gravitation on solar-system scales.
When one enters entirely new territory, the understanding derived from single reliable measurements can be quite substantial.
Since we know exactly what we're looking for and exactly where it should be, we have all kinds of neat radio tools to bring to bear on sampling a faint signal from interstellar noise.
Eventually, its power source will die out, its components will fail, or enough cosmic rays or debris will corrupt enough of its systems it can no longer transmit.
Given those factors, I do wonder what the expected lifetime of the probe is, with the power source being the most clear "game over" line.
It appears that both Voyagers are slated to have some experiments disabled soon (2020 and 2021) to best use remaining power from the RTGs, but since the RTGs are nuclear sources, the decay rate is independent of power draw (it's more an issue of switching off the experiments to avoid peak draw killing the ship).
Voy1's expected to lose too much wattage to turn on the radio by 2025; I can't find a quick number for Voy2.
EDIT: It appears Voy2's power package was expected to allow mission operation through 2020, so sayeth Wikipedia; no idea if that implies the radio was expected to die this year or this was the year the craft would need to be reconfigured for a scaled-back mission profile to maintain enough power for attitude control and radio transmission.
If the probes still had enough power by then, the current DSN would be able to receive data until the mid-2030's.
Can someone tell me what "supersonic" means in a near vacuum?
It does matter, because at some density there are no sound waves anymore. You can’t have sound waves if particles do not collide with each other. And also speed of sound goes down as density goes down. So for this extremely non-dense plasma it’s unclear how “sound wave” is defined.
>I assume it's being compared to the speed of sound through Earth's air.
That roughly 1.2 km/h in space that is nothing. Solar wind are like a 1.6 million km/h
- ed ignore this, I actually RTFA - it's talking about plasma, not itty-bitty matter!
Reading the article it would make much more sense to say: Density of Matter in Space Outside of the Solar System.
So density of space is mass per unit volume of space, not space per unit volume.
It felt like saying “the velocity of distance”
https://electronics.stackexchange.com/questions/321186/is-it...
If that isn't much, run slower and coherently combine more data. White noise power with averaging will fall with the reciprocal square root, while your coherent signal power will add linearly-- eventually you overcome the noise assuming your transmitter/receiver oscillators are locked well enough to sum coherently.
If the noise is not white, e.g. if there are tones in it-- these steps work less well.
Now consider how direct sequence spread spectrum works:
I take a slow signal-- like a 50 bit per second 100Hz wide BPSK signal-- and spread it out by xoring it with a fast random sequence (say a 1MHz random sequences).
The result looks like noise. But if you xor it again you get the original signal back.
When you transmit it, the receiver gets a sum of your signal and noise sources. We can analyize each separately: If you xor white noise with your random sequence -- nothing much happens: you end up with white noise with the same power. So when the receiver xors the received signal with the random sequence, as mentioned nothing much happens to white noise. But any tonal noise gets converted into white noise (because it is independent of the random sequence), and your transmitted signal is recovered and ready for reception using a narrow locked filter.
Modern digital communication almost always uses error correcting codes which allow perfect reception even when some bits are corrupted (early space probes were among the first applications of powerful error correcting codes).
https://en.wikipedia.org/wiki/Matched_filter
They allowed to reach crazy signal/noise ratios.
Digital formats, error correcting codes, wide band (to avoid narrow occlusion from stopping us from recieving), redundancy of transmissions, long bit frames that allow us to average our readings (at the cost of bitrate, akin to long exposure photography)
Seeing as energy is never lost, they just bounce around interstellar space until caught up in a heliosphere of a star system.
Either way I love how the Voyager probes are literally giving us first real impressions of the universe beyond theories.
Starship estimated payload to LEO: 100 t
Voyager mass: 1,820 lb
Booster: let's assume an ideal state of 1 Raptor engine (3,300 lb) and 5,000 lb of other stuff before fuel
Plugging into the rocket equation and assuming no further staging, that gets us a delta v of 89,428 mi/hr, or about 2.3x the speed of Voyager 1. I'm not sure if we should add the orbital speed of Earth to that or not. Also keep in mind that the Voyagers reached their speeds thanks to several gravity slingshots, so in theory we could boost our Starship speedball probe even higher than that. If we used a fat Ion engine instead of chemical rockets, we'd get a lot more delta v as well (although over the course of years instead of a few minutes).
Also it's important to note that Starship isn't really optimized for such missions due to its high dry mass. It's made to bring a lot of mass to orbit cheaply, not really to accelerate it very fast.
Anyway, yes, of course there are countless variations that can be done to make it work. Sticking a Centaur or two in a Starship also seems to be viable. But the parent comment specifically asked about Super Heavy/Starship here.
That would provide the data to help nail this. Equally, what effect will this have upon the amount of matter in the universe and the hunt for dark matter/energy.
But logically, the gravity effect given the time of the universe, it is plausible that would be clustering (solar systems) and in-between those the viability of more matter in space and as such, density becomes plausible - so may explain what we are seeing here. Now what I'll be interested in is will the Voyager probes speed up, slow down or no change. The extra density will in theory slow them down, equally the weaker effects of gravity from the solar system would become less of a factor - might be they balance out for a period and may of already seen this. Still, value for money - Voyager is the gift that keeps on giving.
Now here is a thought, will the mass of the voyager probe in an environment in which it is the the most influential gravity start to build up these space particles. If that is so, who know's, the probes may well go on to attract enough mass that over billions and billions of years go onto form their own solar systems. Now that would be mind blown.