a thoughtful web.
Good ideas and conversation. No ads, no tracking.   Login or Take a Tour!
comment by goobster
goobster  ·  1561 days ago  ·  link  ·    ·  parent  ·  post: NASA's Mars Lander 'Mole' Is Digging Again as Marsquake Mystery Baffles Scientists

It did bounce around for like 10 years, or something, and was supposed to go to Venus, then the Moon, and finally Mars.

My guess is that the tech hasn't been updated, because the nature of NASA projects is that if you change ANYTHING, you have to resubmit the project like an entirely new one. So old shit is constantly getting flown, simply because it has weathered the test of time... and zero advancement/innovation/improvement.





kleinbl00  ·  1560 days ago  ·  link  ·  

'97 if I recall correctly. Thing is? It's newtonian physics. You would literally assign this as an undergraduate engineering problem. If you have the mass of the hammer, the area of the piton, the coefficient of the point and the coefficient of the cylinder you can calculate whether it would work. Better yet, arrange the equation as a function of static/dynamic coefficients of friction and solve for maximum coefficient of friction for it to work, then compare with existing measurements. Nothing here is beyond good old fashioned quadratic equations.

Imagine if the CIA had a self-burying contact mic. How ubiquitous would that thing be? What about a device that could pull its own data cable? The level of specialization here should be available at Home Depot.

I don't see how it survived basic feasibility. Either I am missing something major and obvious or this thing wasn't so much "designed" as "hoped" into existence.

Devac  ·  1560 days ago  ·  link  ·  

The funny thing is that only about a year after that hammer paper was published, researchers found out that Martian soil simulant can be compressed into hard bricks through hammering.

Maybe we really shouldn't into space.

kleinbl00  ·  1560 days ago  ·  link  ·  

LOL they think martian soil is adobe. Because why wouldn't it be. You can do that with "dirt" all over the American Southwest because it's volcanic.

    The engineers believe that the iron oxide, which gives Martian soil its signature reddish hue, acts as a binding agent. They investigated the simulant's structure with various scanning tools and found that the tiny iron particles coat the simulant's bigger rocky basalt particles. The iron particles have clean, flat facets that easily bind to one another under pressure.

That's gonna respond real well to shear and lateral compression.

I keep thinking back to the power profile of that little thing - it's not even a cordless screwdriver. It's like an electric toothbrush. That is somehow supposed to drive itself through sixteen feet of dirt. And NASA people are generally smart so I keep wondering what the fuck I'm missing.

Here it is working.

goobster  ·  1560 days ago  ·  link  ·  

Alright. This just got weirder.

This project is NOT American. It's not some dopey narrow-minded NASA geek, who has never been outside of ABQ, designing something definitely unworkable.

It's GERMAN.

Now THAT makes it even MORE complexing! What the hell are we missing here...? Who thought this was a good idea? How was it tested? What types of calculations did they make to allow for the lower gravity, and composition of the Martian soil? Or if it happens to hit a sub-surface PEBBLE 3 inches down in its 5-meter journey??

kleinbl00  ·  1560 days ago  ·  link  ·  

Penetrator is Polish, yo.

goobster  ·  1559 days ago  ·  link  ·  

Oh right. Misread that. The heat sensor is German/ESA. The penetrator is...

... nah... let's just let the last word be penetrator

kleinbl00  ·  1559 days ago  ·  link  ·  

I suspect that diffusion of responsibility has been a major theme throughout this particular instrumentation package.