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Ancquar t1_iv9d55t wrote

Replying to [deleted] (#455,046)

Mars is in fact supposed to have been a water world.

I have zero information on this myself, but wikipedia says "The volcano's outer edge consists of an escarpment, or cliff, up to 8 km (5.0 mi) tall (although obscured by lava flows in places), a feature unique among the shield volcanoes of Mars, which may have been created by enormous flank landslides."

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SayuriShigeko t1_iv9h4nh wrote

Nasa apparently has an article about their understanding of this actually: https://www.nasa.gov/mission_pages/MRO/multimedia/pia12992.html#:~:text=Most%20scientists%20think%20the%20the,rocks%20it%20is%20built%20of.

Tldr: it's not traditional erosion from water or wind, nor is it tectonic in nature. The edge collapsed in a landslide. As the volcano erupted over time it built up more and more depositted material in layers, and eventually the mass became too heavy for the bottom material layer to support so it crumbled and caused a land slide.

(Paraphrasing and a little filling in of the blanks here, I honestly only skimmed it out of curiosity, I would suggest reading the article if you really want more details)

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bobfossilsnipples t1_ivafmik wrote

Another theory that’s gotten some press lately is that the volcano initially formed under a mile or more of ice, much like the shield volcanoes in Iceland. This can (apparently; I’m a geology hobbyist at best) lead to those steep reliefs. Here’s the original paper discussing the theory. I know I’ve seen some recent publications showing more evidence that’s come from the latest Mars missions, but I can’t seem to find them at the moment.

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Zoomalude t1_ivak7pt wrote

Replying to SayuriShigeko (#455,353)

I don't understand why this would happen that "low" from the massive weight but not higher up where there's even MORE weight. Like, why wouldn't the whole thing have a massive collapse or like one big side of it at least?

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evranch t1_ivalv0z wrote

Replying to dirtyuncleron69 (#456,682)

Great link, such detailed study into a niche problem with wide ranging effects.

I've always thought there was something behind the higher failure rate of electronics post-ROHS, and it's interesting to see that milspec still requires lead in coatings. Personally I still use lead solder and find a lot of failed modern electronics can be repaired for good by simply reflowing them with a touch of 60/40.

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TheGrandExquisitor t1_ivaqyyi wrote

Replying to Zoomalude (#456,935)

This is a very complex structure. And at this scale (which is MASSIVE...I mean the footprint of Olympus Mons is pretty much equal to the entire area of France. Oh, and it is 25km tall. There is a lot going on in there.

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SashimiX t1_ivatl42 wrote

Replying to [deleted] (#457,222)

Full quote:

– If the pedal is depressed quickly, then throttle is limited to 15 degrees
– If the pedal is depressed slowly, then throttle can jump to 15 degrees, and further pedal application can achieve wide open throttle
• In all cases, releasing the accelerator pedal closes the throttle, and brakes are fully operational
– Although the vehicle would operate, we did not consider it to be driveable

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brokenaloeplant t1_ivb897f wrote

Replying to Zoomalude (#456,935)

For the material in the middle, it's all surrounded by crystalline rock. It would have nowhere to collapse into, unlike the edges. If there was a ton of air captured inside or there was a hollow cavity like some kind of sink hole, then maybe.

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mrbombasticat t1_ivbbzqt wrote

Replying to [deleted] (#457,106)

e.g. in an Revisionist history podcast episode they concluded it was and is pedal confusion almost every time.

Even if the gas is stuck (which happened sometimes with after market floor mats according to the NHTSA) the brakes can easily overpower the engine in every car, which they tested in a 500hp car.

So for a car to get out of control without pedal confusion the gas has to get stuck and the brakes have to fail at the same time.

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KingZarkon t1_ivbs6ap wrote

Replying to mrbombasticat (#458,143)

From another comment I made, if your throttle is running wide open, then you lose engine vacuum. You have what's in the vacuum reservoir but that's it. Without regenerating it, you have enough to hit the brakes once, maybe twice with good power. After that, there's little chance a person could push the brake pedal hard enough to overcome the engine at full throttle. I suspect these tests have not taken that into consideration.

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doug-fir t1_ivcifyx wrote

Replying to theelous3 (#455,872)

I remember back in the 1990s, NASA produced aerial photos showing the the liquidation of old growth forests in the Pacific NW was worse than the destruction of the Amazon. That opened a lot of eyes.

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Tunafishsam t1_ivcm39e wrote

Replying to dirtyuncleron69 (#456,682)

Seems like they found an unrelated manufacturing defect. Their summary seems to say that quickly depressing the throttle resulted only in 15 degrees of throttle. That's the opposite of the "stuck" accelerator problem.

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VertexBV t1_ivcptby wrote

Replying to l337hackzor (#459,325)

I don't get the feeling the hand brake on my Civic is good for much more than parking. It takes quite a bit of force to achieve the same braking in motion you'd get with a light touch of the foot on the pedal.

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TheGrandExquisitor t1_ivctrs6 wrote

Replying to willun (#460,111)

As I recall that is true. It can basically be walked up with no special equipment (theoretically of course...I don't think it is that smooth, but the issue would be the local gradient, not the overall gradient.)

That is, after you get up the 7000 meter escarpment. That seems like it would be slightly more difficult.

But hey, after that the next 300km are easy!

I've always wondered if Olympus Mons wouldn't be an ideal place for a Mars based telescope. I think the top is almost out of the atmosphere.

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l337hackzor t1_ivcv7mn wrote

Replying to VertexBV (#460,159)

You might be surprised. I suppose if the engine is applying force it probably won't do much but you can stop a car with it otherwise.

We had to do it in driving school. You want to gradually apply the brakes while holding down the button otherwise you can throw yourself into a skid.

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akmacmac t1_ivd9edv wrote

Replying to KingZarkon (#458,844)

I disagree. Not all cars have vacuum operated brake boosters. Also there was a time when no car had a brake booster or power steering. You can still stop without a working brake assist, it just requires more force on the pedal, just like you can still steer without power steering.

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willun t1_ivddkdq wrote

Replying to TheGrandExquisitor (#460,322)

Mars atmosphere is thin, almost a vacuum being about 1% of earth. Something those who are big on Mars colonies get upset if you remind them. So it may not make much difference.

A telescope on the moon would be easier than putting on Mars but i guess if you were going to do it on Mars than Olympic Mons would be a good place. We put them on volcanoes on Earth frequently so there is lots of precedence.

The moon has a lower rotation speed so probably has other benefits too.

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