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Comment Re:Why does the ESA have a worse record of landing (Score 1) 59

I appreciate the explanation, but isn't it more that the new system was added in rush (to replace the old ones) as opposed to it being the first time used? It seems like the NASA successes were first time uses of those landing systems also, from what I remember.

Also, I really don't understand how IP applies since these are not products for commercial sale nor used for commercial purposes. I don't see where NASA could even bring a suit.

Comment Not Practical (Score 1) 108

You can't just handwave away the massive cost of proving a charger per parking space, nor even the cost of an outlet per parking space along with the electrical lines buried capable of having every single parking space drawing enough current to charge...

Even if that were practical what exactly do you imagine will happen to someone's personal charging cables or equipment left unattended overnight. Thieves are taking copper pipe out of buildings with the water still on...

Comment 3D first, self-flying much easier (Score 1) 43

Great. Let me know when it's bulletproof in a 2D environment and I'll consider the 3D version.

That's actually backwards. Solving for the 3D case is vastly simpler, because while in the air you have very few obstacles to content with, you basically just have to be sure you can react to other planes, and have programmed in the coordinates of no-fly zones - otherwise travel is just a straight line. There are already drones that can find their way back home if the control signal is lost, and almost drones that can fly around tree branches without hitting them...

For takeoff landing you can simply dictate that a solid volume of sufficient space must be below or above you to land/takeoff.

Comment Re:I say BS (Score 2) 108


And I'm telling you that lithium-ion batteries are not a "single tech", that they've dramatically improved in power and energy density (both volumetric and gravimetric) over time. And if you doubt this, I repeat: go find and older lithium-ion battery and compare it to a new one.

As for li-air, yes, the maximum energy density of li-air is about 10x of the maximum of li-ion. Namely because it works by direct oxidation rather than intercalation, so you don't need the mass of the matrix into which the ions get intercalated. It is not a "magical tech". It exists. Like all technologies in all fields, however, you have to reach production specs. This means not only maintaining a combination of safety, reliability, longevity, efficiency, temperature range, power density (charge and discharge) and energy density, but also affordability in mass production. And to be able to guarantee that you can do all of these things to a high enough level for investors to take the risk.

As with all technologies, you start out with promise in one or two fields, but serious problems in many others that you have to deal with. With time you refine them, until all of refined to a state where the product is commercialized. Li-air has actually been advancing quite well. In the early days one of its biggest problems were efficiency and longevity, but they've made huge strides in both in recent years. Lithium sulfur still looks nearer term, but commercialization of Li-air appears to have gone from "possible" to "quite probable".

Comment It can be solved - the solution is Hydrogen (Score 1) 108

I've noticed that also in the past when traveling and staying with friends in Europe.

That's why I still think the future for most electric cars will end up being hydrogen, not battery power - though with advancements like these battery may be a higher percentage, especially if you could go somewhere just one day a week to spend a half hour charging.

Comment Normal is not what you think (Score 1) 108

Long charging times are for most people only a problem on vacation. Normally people commute much shorter distances than the maximum modern electric cars can drive and can charge their cars at night.

I love how you say "normally" when the vast number of people who have cars live in apartments where it may not be "normal" to have a plug anywhere near the car at night.

Is your goal to have electric cars for only the elite? Or for EVERYONE? If electric cars are to break out of a tiny niche for the rich they have to work for people who do not own homes.

Comment That would be the real game changer (Score 1) 108

Non-electric cars are simply more practical for most people not just because of range, but also charging time. Even Tesla Supercharger stations take way too long for most people to tolerate.

But if you have 1000 miles of range, suddenly it's much more practical to live with a very long charging time because you can wait a day or two to find a good charging solution - plus it would mean you could get somewhere faster than with a gas vehicle since you wouldn't have to stop on a long trip to fill up.

We'll see if the tech actually materializes in real life, but I really hope it does.

Comment Re:Halfway There (Score 2) 372

Right. Out of the 330 million people in the US (not counting the broader market, there's "nobody" who wants a gun that can't be accidentally picked up and used by their young children or an intruder. Literally "nobody". Yeah, totally believe you.

They have a niche. You want to prevent them from filling it.

Comment Re:Progress! (Score 3, Interesting) 108

Actually, that is a concern. Li-ion batteries don't have lithium metal in them unless something goes wrong. Lithium-air batteries always have lithium metal in them, by design.

In practice, you'll probably see a bit of the energy density given up in order to beef up the casing to prevent rupture/fire.

Thankfully, lithium-sulfur batteries don't use lithium metal, just lithium polysulfides. The max energy density isn't as high, but it's still quite good. They're already on the market, albeit in small quantities for applications that require the absolute highest rechargeable energy density (mainly aerospace).

Comment Re:I say BS (Score 2) 108

Yes, cue the standard "Batteries haven't advanced!" stuff from people carrying around cell phones with significantly more amp hours in a smaller battery profile than the last generation phones that they owned.

News flash: every time a new tech advance makes it into a product, they don't mail a letter about it to everybody who read an article about it years earlier. Example: hey, remember all of that stuff about breakthroughs in silicon anodes several years back? Yeah, they're in batteries now. Even Tesla is starting to use it in their higher-end packs.

Comment Why does the ESA have a worse record of landing? (Score 2) 59

First of all, I don't see much mention that they still have a new satellite in orbit around Mars so the mission is at least partly successful.

But with a string of failures to land on Mars from the ESA, and a string of successes from NASA you have to start to wonder - what is it that is lacking in the ESA program that is not able to get landings right? Is it just different approaches to the problems of landing that are not panning out over a few attempts? Is it some kind of engineering process failure that they just are not accounting for some possibilities? I was wondering if anyone had any insight.

I wish the ESA the best of luck and really want to se them succeed, as the more craft studying mars the better (though they are all a handful of beans in comparison to the first human to land and study there).

Comment Re:Useless for any occasion (Score 1) 372

You mention hunting - is it really a quick draw sport where if the reader takes an extra few seconds to recognize you, it's a critical failure?

Yes depending on what you are hunting, sometimes you have only a moment, and you never walk with guns at the ready.

I don't even bother to read the rest of what you wrote, it's so absurd to argue with someone with zero understanding of the subject. It would be like trying to discuss the drawbacks of various design patterns with a toddler...

Comment Re:67% is not that good (Score 2) 116

It's good for the NAO. When you're pushing the boundaries, anything over 50% is good.

For long-term climate models, things like the NAO average out across many years. For short-term weather forecasting, you have a week or more before the system diverges enough to cease to be useful. But it's tougher working on those in-between scales.

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The Shuttle is now going five times the sound of speed. -- Dan Rather, first landing of Columbia