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NASA's Perseverance rover sends stunning images

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Re: NASA's Perseverance rover sends stunning images

#341
post #181

Earlier quoted context omitted.

My question is why was the “sound of Mars” release only 18 seconds long? Why not record hours of what it sounds like to be on another planet? Even the sound recordings from decades ago on (I think Titan) was only a short creepy clip. I understand it’s mostly going to be wind and interspliced with the robots sounds but I still don’t get how we don’t have hours of Mars already.

One of the most beautiful and haunting things I've ever heard was a tape cassette that had EM signals recorded by Voyager transposed into human-audible sound domain somehow. It was like whale song of space.

I found it here (there's a series on other planets/moons as well in the recommendations):

https://www.youtube.com/watch?v=LIAZWb9_si4

And Cassini flying into Saturn https://www.youtube.com/watch?v=hWHLCHv4PiI

I wonder what it sounds like to leave the atomosphere now too, I guess this is as close as we can get in the near future. Even with probes going 15km/s.

Re: NASA's Perseverance rover sends stunning images

#342
post #340

Earlier quoted context omitted.

(The question as to how - and why or why not - we could go from the Aeolipile to full blown steam engines, I've always found fascinating ... ... what other things / proceses / materials / frame of mind made the steam engine possible vs. this. What made for an industrial revolution in the 1800's vs. the 1st century AD).-

One thing that severly hampered the romans was their number system.

Makes sense that it would ...

Re: NASA's Perseverance rover sends stunning images

#343

Earlier quoted context omitted.

a $100k here, a $100k there, suddenly, we're talking real money.

Oh we're talking real money. JPL will destroy 78 production grade parachutes to find all the ways they can break. There is tremendous energy poured into eliminating risk, because launch is so expensive. As it becomes cheaper, perhaps these measures won't be as necessary.

With Spacex being able to launch a car out beyond the orbit of Mars, is their current capability being considered for future JPL missions? Or is everything waiting on Starship?

Re: NASA's Perseverance rover sends stunning images

#344

Earlier quoted context omitted.

The reason for that high of a price tag is that the engineering costs are spread over a very few units. If they made 100,000 of them, the costs would be much closer to the materials cost.

> the costs would be much closer to the materials cost Which is? Not cheap. And it's not like you can buy in any corner store. And no, while an "economy of scale" would make it cheaper, it doesn't mean it would be cheap.

I never said they would be affordable even in qty 100k.

I would think the major use for them beyond space probes would be providing last resort backup power/heat for life support on outside earth orbit space habitats/crewed vehicles as the cost will still be at least $500/watt.

Re: NASA's Perseverance rover sends stunning images

#345
post #248

Earlier quoted context omitted.

Very low bandwidth, very low power, very long distance comms are really cool. The limiting factor tends to be the clock frequency precision - if you have precise enough clocks at both ends, there isn't anywhere in the universe you couldn't communicate with, as long as you're happy to go slow enough.

> there isn't anywhere in the universe you couldn't communicate with Right, assuming you are emitting infinite amount of photons, there are no obstructions, black holes and you ignore universe expansion and GR which can make your precise enough clocks go out of sync.

> emitting infinite amount of photons

I think that the double slit experiment shows that this isn't an issue... Since we are summing with all other noise in the universe, it doesn't matter exactly which photons came from my transmitter, if any at all, but the total count will still (probabilistically) reflect the the we're after...

Re: NASA's Perseverance rover sends stunning images

#346
post #86

Earlier quoted context omitted.

A lot of those effective waste disposal systems in the West, particularly for recycling, consist of paying Asian and African companies to take away the waste, so it can then be dumped in their countries/oceans or get "recycled" in places like this: https://en.wikipedia.org/wiki/Agbogbloshie

No, that is not a waste disposal system, it's how tech companies and other companies that sell gadgets fool their eco customers into thinking they are "recycling" something that cannot in principle be safely recycled. It is yet another example of going through a kabuki ritual rather than effectively dealing with the problem.

It's not only recycling. Currently, in my area of Poland there are gangs which bring toxic industrial waste from Western Europe in large quantities and just dump them wherever, while collecting the fee from industrial clients for properly disposing of them. This is a very recent trend, that was, from what I've read, started by China no longer importing European waste. You can only imagine how often "disposing of" such waste in China consisted of dumping it into a forest or pouring into ground or a river.

Re: NASA's Perseverance rover sends stunning images

#347

This mission is an incredible achievement. The images are as advertised (stunning) and I'm sure all the sciences - and even art - will benefit from the data. What I find a little sad is that we seem incapable of doing this without leaving a particularly human signature wherever we go. We arrived on Mars with jets of pollution https://mars.nasa.gov/resources/25672/black-and-white-smoke-... followed by the dumping of t…

We're disturbing all those pristine impact craters.

Re: NASA's Perseverance rover sends stunning images

#348
post #227

Earlier quoted context omitted.

> The reality is that the reason we do these things is to make ourselves feel better. Ah, yes, my daily shot of endorphins from recycling. Ah yes, my bumper sticker makes sure everyone knows I'm one of the good ones -- my social standing is safe Speak for yourself my friend. The idea that people only make changes, even little ones entirely out of self service is extraordinarily cynical and a very negative and sad vie…

The idea that people only make changes, even little ones entirely out of self service is extraordinarily cynical and a very negative and sad view of the world. You keep saying that. It's subjective, and it's not an argument. George Bernard Shaw said, The power of accurate observation is commonly called cynicism by those who have not got it. Say I tell my friend and they decide to do the same thing, now it's 1000 piec…

> George Bernard Shaw said, The power of accurate observation is commonly called cynicism by those who have not got it.

I think you should double check to make sure your "accurate observation" and "clear eyed" thinking is not tainted by your own biases. It's very easy to consider ones own view the accurate one without ironing out the biases learnt or inherent to you.

> Well that's imaginative but it seems highly unlikely. After all, if everyone is so highly primed to change in this way, and all it takes is one person to spark the fire... chances are enormously likely it would have happened already, and it would have happened without you needing to spark it.

They have. Millions of times in fact! Human history is always changing and growing from little things and big things too. The world of today looks drastically different to that of 30 years ago, or 90 years ago or 500 years ago!

> This idea that you're at the center of a movement to change the world is just more subconscious ego feeding. If you want to be at the center of a movement that changes the world... it's going to take a lot of hard work.

It's not about being the center of a movement to change the world, and the fact you keep jumping back to that shows that you don't understand what I'm saying. You look at it in that lens because you want to, but it's just about doing minor good things for it's own purpose. A simple autotelic action. It's honestly that simple, but the end result of a lot of people making that simple choice is a changed world. It's not about feeding ego at all. It's also not about building a movement, at least not directly. It's about convincing those around you of the value of doing something small that improves things even insignificantly because combined they have massive impact.

Enjoy your "clear-eyed view" of the world, I know you've convinced yourself you're 100% correct.

Re: NASA's Perseverance rover sends stunning images

#349
post #248

Earlier quoted context omitted.

> there isn't anywhere in the universe you couldn't communicate with Right, assuming you are emitting infinite amount of photons, there are no obstructions, black holes and you ignore universe expansion and GR which can make your precise enough clocks go out of sync.

> emitting infinite amount of photons I think that the double slit experiment shows that this isn't an issue... Since we are summing with all other noise in the universe, it doesn't matter exactly which photons came from my transmitter, if any at all, but the total count will still (probabilistically) reflect the the we're after...

On long distances you are talking about receiving single photons. And while we may view it as probabilistic, it will either interact with our equipment or it won't. If it doesn't, communication failed.

But yes, I wondered about that when writing my comment. Certainly photons are more than just "bullets" that are getting more and more sparse. So I got curious and it seems[1] that in context on our detector you can indeed put hard bounds on where the photon may be received. As far as I understand it, based mostly on the abstract, I do not really grasp it.

But ignoring the paper, I think I get your point. If photon has any chance of reaching the target (even lower than virtual particle spawning) and even if you don't know the future of the Universe (other photons hitting detector), you can use some complex encoding so that observing certain (allegedly otherwise unlikely) patterns allows you to say you received some message with some probability (which is what communication always is). If you have synced clocks. Simultaneity is relative though so there's also that.

1. https://arxiv.org/pdf/0903.3712.pdf

PS. I seem snarky today, sorry about that, I'm happy to learn if I'm misunderstanding something.

Re: NASA's Perseverance rover sends stunning images

#350
post #85

Earlier quoted context omitted.

Risk? That is my basic opposition. Happy to be flexible on energy in almost every way. Cost, type, uptime... But error with nuclear tech tends to endure for a very long time. Fukushima will be raising ocean radiation for a long time, just one example. These are many lifetime events. Some minor, or recoverable, some profound. Given we can reasonably run the fridge on solar, and other tech, that risk does not seem to m…

> Fukushima will be raising ocean radiation for a long time, just one example. Will it? The ocean is very, very big. Contaminated water from Fukushima is a literal drop in a bucket.

Already is. Drops over say, 10 to 100k year timelines add right up.

The solution to pollution is dilution.

I say that in jest, because dilution involving radioactivity works on much longer timelines than many things do.

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