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NASA's Perseverance rover sends stunning images

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Re: NASA's Perseverance rover sends stunning images

#61

Post by medium_burrito »

perardi wrote: post #40
medium_burrito wrote: post #22

Earlier quoted context omitted.

You triggered the fuck out of me. The saving grace of the Joint Strike Jobs program is that maybe 1% of the people learned what to do next time.

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 whole get 10+ prototypes from various places, stick them in a big ass vacuum chamber, and try to make them fly was interesting. Turns out a torque rotor doesn't work there.

With $80m, the military industrial complex would figure out that pink and yellow don't work well for urban camouflage.

Re: NASA's Perseverance rover sends stunning images

#62

Post by azernik »

jerkstate wrote: post #7

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?

Data comes from Perseverance through two channels:

* A low-bandwidth direct link to Earth (160bps-800bps depending on receiver dish- no, that's not a typo)

* A high-bandwidth link to orbiting satellites, which then forward traffic to Earth (~2Mbps for the rover->orbit hop, anywhere from 0.5-4Mbps for the orbit->Earth) .

I strongly suspect that the low-bandwidth telemetry signals - equivalent to the homemade reception from satellites I've heard of - are sent in the clear. Bandwidth is just too precious to waste.

I would not be surprised either way for the image data - on the one hand, computing power is relatively scarce, while on the other hand it already has to go through a compression pipeline.

https://mars.nasa.gov/msl/spacecraft/rover/communication/

Re: NASA's Perseverance rover sends stunning images

#63

Post by 0x003 »

moltar wrote: post #35
idiocrat wrote: post #17

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…

One person doing something in the face of billions of others is the entire opposite of pointless. Giving up because you're one person and you can't magically transform the entire world is cynical, a cop-out and completely misunderstands the nature of the problem.

The world won't change overnight, it won't immediately flip from the actions of one individual, or two, or even 1 thousand or 1 million. But that doesn't mean the action is pointless.

Change requires momentum, momentum requires the actions of an individual diligently living the change they want to see and sharing it with others. That sort of change builds slowly, often imperceptibly. But before you know it things begin actually changing. So no, this binary attitude of "You can't change everything by your actions so you may as well do nothing" is such an apathetic, cynical cop-out and I hate seeing it spouted everytime you see someone do something positive. As an idea it literally does nothing but harm and it has no value in being said.

Re: NASA's Perseverance rover sends stunning images

#64

Post by neolog »

marshmallow_12 wrote: post #52
11thEarlOfMar wrote: post #44

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?

I'd be interested in a real answer to this if any nuclear engineers are around

Re: NASA's Perseverance rover sends stunning images

#65

Post by malwarebytess »

Stunning? Boring is the truth. They look as haphazard and unconsidered shots of earthly, unremarkable, landscape.

NASA needs artists and poetic photographers to capture inspiration on Mars if they want to snare the hearts of the public. What a waste of fortunes if they cannot do that.

If only the images were as great as the feat and engineering itself.

Re: NASA's Perseverance rover sends stunning images

#67

Post by medium_burrito »

evilos wrote: post #57
AnimalMuppet wrote: post #50

Earlier quoted context omitted.

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.

Inquiring minds would love to know about a practical solution. You can add more material, but that's extra bulk and weight. I think we can agree that a mountain is bullet proof, but that's not really practical.

Also, rifles are really good at shooting through shit. We're talking rifles from 1890s. People don't realize that a bullet from a rifle punches through steel plate (and then buy steel body armour like the plebs they are). Modern ar15/ak rifles are wusses by comparison- we traded big badass bullets for smaller ones that are lighter and easier to carry.

More awesome weapons like the rpg-7 basically create a stream of molten metal that goes right through armored vehicles. Or you use depleted uranium or tungsten, which get more dense as they heat up from friction of punching through things.

In the near future we'll have even more badass things like railguns that will go through meters of steel/ceramic/admantium.

So yeah, that mountain may not save you. Meanwhile, mars will be the same.

Re: NASA's Perseverance rover sends stunning images

#68

Post by dredmorbius »

teleforce wrote: post #37

This is a video presenting ten milestone images that revealed what we've learned about Mars after decades of exploration prior to the landing of Perseverance [1]. It's nice to see the evolution of image resolutions of the Red Planet. [1] https://www.youtube.com/watch?v=e1eFMzO3iPc

Similar, a gf capturing the evolution of our knowledge of Puto in somewhat less than a century: https://i0.wp.com/www.nasa.gov/sites/default/files/styles/fu...

Re: NASA's Perseverance rover sends stunning images

#69

Post by shkkmo »

marshmallow_12 wrote: post #52
11thEarlOfMar wrote: post #44

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 8 figure price tag for a RTG makes consumer use uneconomical.

Re: NASA's Perseverance rover sends stunning images

#70

Post by junon »

ryandvm wrote: post #56
marshmallow_12 wrote: post #52

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?

Do you have an answer that isn't speculation or something you concluded from a breezy stroll over to Wikipedia?

Stop mocking questions. It solves nothing.

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