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NASA's Perseverance rover sends stunning images

bbc.com

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Re: NASA's Perseverance rover sends stunning images

#251
post #43

Earlier quoted context omitted.

The issue is that 90% of the plastic in the ocean is dumped from 10 rivers in Asia and Africa where the waste disposal system consists of driving a truck up to a river and dumping the trash in. Of the remaining 10%, it comes from Latin American nations that do the same thing. Meanwhile western people see these masses of trash and plastic in the ocean and conclude the rational response is to ban straws in the western…

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

From your own source:

> While numerous international press reports have made reference to allegations that the majority of exports to Ghana are dumped, research by the US International Trade Commission found little evidence of unprocessed e-waste being shipped to Africa from the United States,[9] a finding corroborated by the Massachusetts Institute of Technology, Memorial University, Arizona State University, UNEP, and other research.[10] In 2013, the original source of the allegation blaming foreign dumping for the material found in Agbogbloshie recanted, or rather stated it had never made the claim that 80% of US e-waste is exported.[11]

Re: NASA's Perseverance rover sends stunning images

#252
post #236

Earlier quoted context omitted.

I doubt a NASA suggestion box open to the internet will be very fruitful.

I for one look forward to Rover McRoverface in the 2022 launch window.

Marvin McMarsface is to take a close-up look at the Face On Mars in 2023 and then implant an Illudium Q-36 Explosive Space Modulator to eliminate Mars because it obstructs our view of Venus.

Re: NASA's Perseverance rover sends stunning images

#253
post #159

Earlier quoted context omitted.

From my layman's understanding, it's relayed via the orbiters. There are a few orbiters around Mars. NASA appears to have an arrangement with the ESA to upload data from the rovers to the ESA's orbiters, depending on whose orbiters are within line of sight at any given time. Then the orbiter sends the information back to Earth, which are received by NASA's Deep Space Network During the time when line of sight between…

It never ceases to impress me that we have the ability to do this sort of stuff. A couple thousand years ago, the height of technology was shooting something from a few hundred metres away with a bow and arrow, now we are landing machines on another planet and transmitting data back and forth through the solar system. Incredible.

A couple of thousand years ago is the peak of the Romans, so you're way off on your 'height' of technology at that time.

Using bows and arrows as an example when you've got wonders of pretty advanced engineering like the Parthenon, plus they also had ballistae, chariots and catapults, so not the peak at all.

Not only that, but even the bows were more advanced, composite bows much more powerful than simple ones made of wood.

Re: NASA's Perseverance rover sends stunning images

#254

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?

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.

More accurately, plutonium is as toxic as lead. It's also a bit more radioactive than lead.

Re: NASA's Perseverance rover sends stunning images

#255

Does anyone know what type of data compression is being used to transmit these images? There's been huge progress since the last rover.

> There's been huge progress since the last rover.

One thing that changed in the last 8 years is that there are now two new orbiters around Mars (MAVEN and ExoMars TGO), which can retrieve data from the rovers faster, cache it and send it to Earth faster.

Re: NASA's Perseverance rover sends stunning images

#256

The bottom of this page says: "All images copyright Nasa/JPL-Caltech" But I thought all works created by the US federal government are public domain and not protected by copyright? Famously the "Blue Marble" photo is not under copyright and reproduced all over the place: https://en.wikipedia.org/wiki/The_Blue_Marble

That's probably just a mistake from the BBC. The original source [1] just says "image credit" NASA/JPL-Caltech, not copyright.

[1] https://mars.nasa.gov/mars2020/multimedia/raw-images/

Re: NASA's Perseverance rover sends stunning images

#257
post #111

Earlier quoted context omitted.

Alpha sources outside the human body are of little health concern. You'd have to break it open and eat the plutonium inside for it to be a serious risk.

How familiar are you with the human species? There have been several notable accidents where humans have cracked open medical machines and decay powered lighthouses to exactly this effect. Imagine if you started whacking plutonium in consumer products!

> How familiar are you with the human species? There have been several notable accidents where humans have cracked open medical machines and decay powered lighthouses to exactly this effect. Imagine if you started whacking plutonium in consumer products!

People already dope silicone bands and fabric (including underwear!) with Thorium and sell them as "negative ion" "wellness" products. Some are still available to buy on Amazon.

Because there's nothing like "wellness" than exposing your gonads to ionising radiation!

Re: NASA's Perseverance rover sends stunning images

#258
The picture labeled "wind carved rock" is interesting. If the atmospheric pressure is 610 pascals or 0.088 psi (less than 1%) earth pressure, how could any wind be powerful enough to carve a rock? Does the wind blow 600-1200 mph on Mars?

Don't answer as the question is rhetorical.

Air pressure that thin would require winds several hundred MPH just to kick up fine dust particles, well before we get to erosion of rock.

With such low air pressure a human would barely feel a 300 MPH wind gust. In that low air pressure a parachute would be useless unless it is 2000 feet in diameter.

A rocket would need 100x the thrust to get the same acceleration or deceleration, as per Newton's law, 100x less resistance means an object in motion plummeting toward the surface would tend to remain plummeting. Remember why they tell you meteors meet resistance and burn up entering Earth's atmosphere? The reverse would be true of a object plummeting through atmosphere of only 610 pascals. 100x more thrust would be necessary to slow the descent to compensate for the lack of atmosphere and the density differential.

Did NASA think of any of the actual physics before they served you this fake Mars landing cartoon? You're hackers. You know how to do math. This is 8th grade physics to see the scam being served up here as scientific exploration.

I suppose if grifters had a 70 million dollar per week budget they might be tempted to produce what was paid for, even if they had to fake it.

Everything shown to you in these Mars landing videos is consistent with parachuting into Earth's atmosphere, not an atmosphere 100x thinner. That parachute would drop almost as fast as a rocket. Remember the falling feather and cannonball in a vacuum analogy?

You're being played. NASA is just a division of Hollywood. Yes, the world is that messed up. And yes the military industrial complex is that shady.

Enjoy your cartoons!

Re: NASA's Perseverance rover sends stunning images

#259
post #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?

The chances of someone unscrewing on Mars are a million to one they said.

Re: NASA's Perseverance rover sends stunning images

#260

The picture labeled "wind carved rock" is interesting. If the atmospheric pressure is 610 pascals or 0.088 psi (less than 1%) earth pressure, how could any wind be powerful enough to carve a rock? Does the wind blow 600-1200 mph on Mars? Don't answer as the question is rhetorical. Air pressure that thin would require winds several hundred MPH just to kick up fine dust particles, well before we get to erosion of rock.…

10/10 satire
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