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NASA's Perseverance rover sends stunning images

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Re: NASA's Perseverance rover sends stunning images

#191

Earlier quoted context omitted.

What's powering Voyager is a plutonium pile. Pretty sure you don't want that in your fridge. 10 billion miles from me? Sure, knock yourself out. 10 feet from me? No way.

AKA "Not In My Back Yard." So the question stands and extends to include this: "why not?"

To add to the other posts: nuclear weapons proliferation

Re: NASA's Perseverance rover sends stunning images

#192
post #189

Looking at closeups of the Rover, I cannot help but think: are those screws, nuts and bolts? And if so, why? Why carry the weight or decreased stiffness of or by the notches, slits, threads etc. that makes screws be screwable. To a place where no-one ever will unscrew them?

I predict that the chances of someone ever unscrewing them are higher than not. Just not super soon.

Plus during development its useful, and why would you change the platform you test when deploying to live?

Re: NASA's Perseverance rover sends stunning images

#193
post #56

Earlier quoted context omitted.

a glowing green sandwich covered in red sand. But seriously, this stuff is powering those voyager probes 40 years later. Which makes me ask: why do we have to send there technologies 10 billion miles away to make them work? Why can't my fridge be powered this way?

Are you really asking why we can't power your fridge with plutonium?

I come to HN because yes, people are really asking and really answering. It’s currently the best forum on the internet for this reason.

Re: NASA's Perseverance rover sends stunning images

#194
post #189

Looking at closeups of the Rover, I cannot help but think: are those screws, nuts and bolts? And if so, why? Why carry the weight or decreased stiffness of or by the notches, slits, threads etc. that makes screws be screwable. To a place where no-one ever will unscrew them?

I'd be amazed if we could build a single-use unibody rover but even so I suppose those bolts and nuts give some needed flexibility when landing and moving.

Any structural engineer around?

Re: NASA's Perseverance rover sends stunning images

#195
post #181
post #87

Stupid question maybe but like is there a reason the picture quality seems worse than a decent dslr photo? I'm so curious what that photo would look like, taken with an everyday camera, without the bizarre 'scientific' look of these shots.

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.

My guess would be bandwidth. Every bit of bandwidth is precious, so they probably dont have the spare budget to send long audio files without obvious scientific value...

Re: NASA's Perseverance rover sends stunning images

#196
I get how exciting this is for planetary scientists, but the last few robotic missions have really driven home that Mars is kind of an armpit. Here's to sending rovers somewhere with cooler visuals. I will stay up all night to see what the Io Lander can send home before it falls into a volcano.

Re: NASA's Perseverance rover sends stunning images

#197

I get how exciting this is for planetary scientists, but the last few robotic missions have really driven home that Mars is kind of an armpit. Here's to sending rovers somewhere with cooler visuals. I will stay up all night to see what the Io Lander can send home before it falls into a volcano.

Not kidding someone could add filters to the images to see different aspects of the view.

Re: NASA's Perseverance rover sends stunning images

#198

Anyone has insights on how data in such volumes can be transferred from Mars to Earth in the absence of a direct link? Do the intermediate nodes have gigabytes of available storage to emit data to the next available node once it becomes visible ?

They added dedicated storage in the rover itself to store phots and videos. So for example they can compress the video files before transmitting. I've hear they use ffmpeg for this purpose. There are 4 orbiting satellites that can relay any data sent to it.

Re: NASA's Perseverance rover sends stunning images

#199

Earlier quoted context omitted.

I would think with the wind and sand storms that it'd be dangerous leaving it exposed for a month before you even get to use it. Does the rover park on top of it during storms for minimal protection?

Right after landing, Perseverance put Ingenuity down on the ground and drove off to give some separation. The winds and sand aren't mechanically very strong - the Martian atmosphere isn't dense enough to transmit much force even at high wind speeds. The only real dangers are obscuring the sun (important because Ingenuity runs on solar power) and getting dust in all kinds of places. But the landing site is pretty low…

I don't think Perseverance moved since landing, and Ingenuity should be still inside the rover.

Re: NASA's Perseverance rover sends stunning images

#200

Stupid question, but where is Perseverance's energy source? Answer: Plutonium It powers a Multi-Mission Radioisotope Thermoelectric Generator. The plutonium decays at a few % per year, so that means it should be able to bring Elon a sandwich when he lands. https://mars.nasa.gov/mars2020/spacecraft/rover/electrical-p...

a glowing green sandwich covered in red sand. But seriously, this stuff is powering those voyager probes 40 years later. Which makes me ask: why do we have to send there technologies 10 billion miles away to make them work? Why can't my fridge be powered this way?

The Russians tried powering a bunch of remote stuff with plutonium batteries during the Soviet era. It did not end well, and cleaning those up has been an ordeal. Pu-238 was also used in pacemakers. The basic problem is just that plutonium is toxic as hell.
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