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NASA's Perseverance rover sends stunning images

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Re: NASA's Perseverance rover sends stunning images

#51

Earlier quoted context omitted.

What do you want before you'll call it "stunning"? Beaches with women in bikinis? Those are stunning for the amount of detail they show of the surface of another planet.

Microbes in bikinis, please

LOL. Not sure why you're being downvoted - microbes with or without bikinis would definitely be stunning.

Re: NASA's Perseverance rover sends stunning images

#52

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?

Re: NASA's Perseverance rover sends stunning images

#53

Earlier quoted context omitted.

They use the same kind of compression as the last mission. JP2, I believe. https://en.wikipedia.org/wiki/JPEG_2000 I'm not sure that data compression has progressed that much since Curiosity in 2012 or Insight in 2018. There have been some formats that have improved compression at the expense of large amounts of memory or processing power, but neither of those are abundant on a rad-hardened processor. Neither is elec…

Any idea how much storage it has? I would think it'd have to be TBs to store all these images, logs, and other data for years while making sure they have enough memory so that they're not limited and if the rover stays there for longer than intended.

Once it's been sent to Earth, they drop it. Curiosity's main computer had a flash drive of 2GB, and each of the big cameras had an 8GB flash drive on board. I doubt Perseverance is much changed from that; the main computer is IIRC a spare part from the Curiosity production.

Rad-hardened computer hardware is expensive and bulky. You don't add storage or processing power that you don't absolutely need.

See https://www.ontrack.com/en-us/blog/how-to-store-data-on-mars and https://mars.nasa.gov/mars2020/spacecraft/rover/brains/

Re: NASA's Perseverance rover sends stunning images

#54

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?

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.

Re: NASA's Perseverance rover sends stunning images

#55

I remember a recent article on HN about being able to receive signals from Tianwen-1 with a homemade satellite dish - is it possible to receive these pictures over radio with the right equipment, or do they come down encrypted?

If I recall correctly, the Tianwen-1 amateur signal reception was (1) shortly after launch, and (2) using a 20 meter dish. Receiving the downlink from a deep space object requires much more sophisticated technology than most amateurs have access to, both to track the object, and to listen hard enough.

That being said, I doubt that the transmissions are encrypted. Hell, I bet some amateurs with a very powerful transmitter might be able to transmit a software update and take control of the rover.

https://xkcd.com/1337/

Re: NASA's Perseverance rover sends stunning images

#56

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?

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

Re: NASA's Perseverance rover sends stunning images

#57
post #40

Earlier quoted context omitted.

Yes yes, I know, it’s trite to point out that boondoggle of a project. Except…NASA apparently spent all of $80 million on a helicopter that will work on Mars. One has to wonder what the military-industrial complex could accomplish with a bit of financial discipline and oversight.

The NASA helicopter had to work at all on Mars. It's amazing that they succeeded. But it didn't have to survive in an environment with Martian SAM sites, or even rifle fire from the ground. That is, the military requirements are much more intense than we often realize.

Surviving rifle fire has been a solved problem since like, the bronze age. Add more metal. Getting to and landing on another planet (intact and functional) on the other hand, is probably like 3 orders of magnitude higher in difficulty.

Re: NASA's Perseverance rover sends stunning images

#58

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?

You know I was about to say something about how your fridge draws so much more power than these probes, but actually I just googled it and they're pretty close. Today I learned.

(I don't know how much power the probes actually use, but anyway the wattage of the RTG itself is pretty close to the steady state power consumption of a fridge.)

Re: NASA's Perseverance rover sends stunning images

#59
post #35

All the extraterrestrial expansion, dream of Men to conquer Space, star track enterprise! I'm pessimistic that we will ever leave our solar system, and if so in 1000 years, I do not care. Hopefully people learn how tiny our bubble is and protect our environment more. The Martian environment looks so boring -- as a replacement for polluted Earth. (We will pollute Mars faster than Earth). I'm living at the ocean, tryin…

I admire your efforts to clean. But unfortunately it’s pointless. There are entire million and billion population countries that treat oceans as waste baskets, simply because they don’t know better. I’ve talked to fishermen in rural Thailand and they don’t have waste collection. So they take their trash every day and just dump it in the middle of the ocean somewhere. They didn’t understand why that was a problem when…

What could they do with the waste instead, if they don't have collection?

Re: NASA's Perseverance rover sends stunning images

#60
post #11
post #9

Is there a single good official site to get Perseverance media from?

https://mars.nasa.gov/mars2020/multimedia/raw-images/ Would be the best place to get images/videos from Perseverance.

Also, InSight: https://mars.nasa.gov/insight/multimedia/raw-images/
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