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NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

blogs.nasa.gov

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Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#271

Post by shiroiushi »

noir_lord wrote: post #264
DeathArrow wrote: post #262

>The team discovered that a single chip responsible for storing a portion of the FDS memory — including some of the FDS computer’s software code — isn’t working. No one thought of having backup computers on the spacecraft?

Most of the computer hardware is duplicated but much of it has already failed/failed earlier - remember these are 50 year old hardware - a lot of the logic is TTL and discrete components - which are far larger than modern equivalents would be.

It's not just 50-year-old hardware: it's hardware that's been subjected to cosmic radiation for 50 years, part of that outside the solar system (so presumably even higher).

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#272

Post by shiroiushi »

NKosmatos wrote: post #261
hujun wrote: post #217

Dark Forest Hypothesis: https://en.wikipedia.org/wiki/Dark_forest_hypothesis

Although that’s one of the many possible explanations of the Fermi paradox [0], I prefer to think that the real reason we haven’t discovered (or we haven’t been discovered) is the fact that we’re limited by the speed of light. The distances are so vast, almost unfathomable, that we need Faster Than Light means of traveling. Perhaps I’m being naive or romantic, but I prefer to think this is the real reason :-) [0] htt…

The speed of light and great distances are indeed a limiter, but the universe has been around for billions of years. Even with the great distances, an interstellar civilization that's been around for millions of years would have had plenty of time to find us by now.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#273

Post by shiroiushi »

nuccy wrote: post #267
somenameforme wrote: post #229

Earlier quoted context omitted.

Inverse square law. With the power we're transmitting at, signals become just background noise relatively quickly. They're nowhere near strong enough to be detectable at e.g. Proxima Centauri. This is what makes the radio signals we do detect, like fast radio bursts, so interesting. So for instance, the furthest signal we've detected is called FRB (fast radio burst) 20220610A, and that millisecond length signal came…

This "law" is only for point (or spherical) sources, i.e. those emitting evenly in all direction - the area is increasing as a square of distance and thus signal power drops accordingly. With lasers, directional antennas, phased array antennas [1] the signal won't decay that fast. For instance with lasers it will be just a matter of alignment of internal elements to obtain a parallel light beam which doesn't lose pow…

>This "law" is only for point (or spherical) sources, i.e. those emitting evenly in all direction

We're not talking about lasers and directional antenna here, we're talking about humans using radio communications to talk to each other on Earth over the last 100 years, and whether that's detectable from great distances.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#274

Post by shiroiushi »

CuriousCosmic wrote: post #204
fsniper wrote: post #114

Good old segmentation and goto's at work! Are goto's still considered harmful?

What's the paper title? "goto considered harmful considered harmful" I think? Even in modern C programming goto is still pulling its weight for handling unrolling and cleanups.

The paper was written by Dijkstra, and even he doesn't like how it's become some kind of mindless mantra, instead of a warning against spaghetti code which it was. He never meant that you should never, ever use GOTO.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#275

Post by randomtoast »

divbzero wrote: post #233
Night_Thastus wrote: post #59

There's something very beautiful about Voyager's journey so far. I hope one day when we're a true interstellar species we'll still keep tabs on it. The data may not be useful anymore, but it would be cool to imagine a year 3000 society with a little "Look at where Voyager is now :)" tool that you can see its path and where humans have colonized by comparison.

I’ve imagined a scene playing out, in sci-fi or for real in the distant future, where astronauts test out a new propulsion system by flying out towards Voyager 1 and catch up to it with ease. As they approach, they see the ancient probe grow larger and larger in their window until…

If my math is correct, we would already need to build a spaceship that can travel at 1/10th the speed of light to reach Voyager 1 within one week. It will be quite an engineering challenge for the future.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#276

Post by T-A »

shiroiushi wrote: post #273
nuccy wrote: post #267

Earlier quoted context omitted.

This "law" is only for point (or spherical) sources, i.e. those emitting evenly in all direction - the area is increasing as a square of distance and thus signal power drops accordingly. With lasers, directional antennas, phased array antennas [1] the signal won't decay that fast. For instance with lasers it will be just a matter of alignment of internal elements to obtain a parallel light beam which doesn't lose pow…

>This "law" is only for point (or spherical) sources, i.e. those emitting evenly in all direction We're not talking about lasers and directional antenna here, we're talking about humans using radio communications to talk to each other on Earth over the last 100 years, and whether that's detectable from great distances.

There is a reason I included radar in my list.

military radar transmissions set up during the Cold War to detect incoming ballistic missiles have the power and frequency characteristics to be detected over hundreds of light-years – and have already broadcast our existence to any aliens within around 60 light-years of the Earth [1]

But never underestimate the power of television:

The most detectable and useful escaping signals arise in a few ultra-powerful military radar systems and in normal television broad-casting. A model including over 2,000 television transmitters is used to demonstrate the wealth of astronomical and cultural information available from a distant observer’s careful monitoring of frequency and intensity variations in individual video carriers (program material is not taken to be detectable). [2][3]

once the Square Kilometer Array is completed in Australia and Africa, it would be able to detect the current TV carrier wave radio leakage at a distance of about fifty lightyears for objects in the southern hemisphere sky [4]

[1] https://www.sciencefocus.com/space/how-far-from-earth-could-...

[2] https://link.springer.com/chapter/10.1007/978-94-009-9115-6_...

[3] https://www.science.org/doi/10.1126/science.199.4327.377

[4] https://www.forbes.com/sites/quora/2017/01/27/how-far-into-s...

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#277

Post by IAmGraydon »

datavirtue wrote: post #155
Night_Thastus wrote: post #59

There's something very beautiful about Voyager's journey so far. I hope one day when we're a true interstellar species we'll still keep tabs on it. The data may not be useful anymore, but it would be cool to imagine a year 3000 society with a little "Look at where Voyager is now :)" tool that you can see its path and where humans have colonized by comparison.

Oh, you sweet summer child...

We get it. You’re scared and want everyone else to be just as scared as you.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#278

Post by bombcar »

peddling-brink wrote: post #85
cancerboi wrote: post #78

Earlier quoted context omitted.

What is this sbnation link? The text explodes and a calendar pops up.

Keep reading. It’s a story.

Existential crisis as football was not on my expected list for today.

Re: NASA's Voyager 1 Resumes Sending Engineering Updates to Earth

#280

Post by kevincox »

shiroiushi wrote: post #263
_yb2s wrote: post #103

Earlier quoted context omitted.

Yep... days worth of work to get Python code I wrote 3 years ago working again from all of the 'bitrot.' Can't imagine how much work it must be for them to produce new binaries to update these old systems from modern computer hardware. Although I suppose it could actually be easier depending on how the code works- perhaps it's just simple bare metal assembly without the approx 10^99999 libraries a modern python stack…

It's probably a lot easier in a way, because they don't have to worry about external dependencies changing at all. Modern code is a real PITA that way. What's hard about their work is 1) it's really, really slow to communicate with, so you can't iterate quickly, 2) the tech is really old and unlike today's stuff, so it's very specialized domain knowledge.

Also whatever you do don't break the receiver pathway! Otherwise you will need to send a technician on-site.
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