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Comment Re:Saw it last night in 3D (Score 3, Insightful) 242

The challenge is stranding someone alone on Mars. It's easy to envision the entire crew getting stuck there. Malfunction in the ascent vehicle would do that. If it had a sufficient electrical meltdown it could even justify the loss of contact with Earth. But getting five people safely off the surface, all of them convinced of the sixth crew member's death and unable to retrieve his body, was a writing challenge. What scenarios can you think of for one man being left alive, alone, and presumed dead on the surface of Mars?

Comment Doing the Math (Score 1) 55

SPOILER ALERT: Spoilers about the first chapter of the book follow! (Because someone is likely to complain about that kind of thing.)

Has anyone actually done the math on this? We are not talking about a man being blown around in a windstorm, really. We are talking about equipment that NASA launched to Mars getting blown around in a windstorm. The ascent vehicle getting blown nearly over is a stretch, for sure, but perhaps the injury that befalls the protagonist is not. It was inflicted on him by a piece of metal that was thrown by the windstorm. I am not qualified to do the math, but I hope someone else here is.

While the protagonist and most likely the ascent vehicle are fairly heavy, presumably everything else that NASA spent rocket fuel to put on the surface of Mars is as light as it can possibly be to still do its job. It would not take much air density to pick up a piece of metal that has high surface area and small mass, like a thin piece of aluminum with a bend in it to make it rigid would be. It certainly could be whipped by the 150kph (42m/s) wind. Anything near that speed and it would not have a problem piercing a spacesuit or damaging a circuit board. Maybe it would not likely have enough energy to do both of those things and still seriously injure a human, but it is at least plausible from this high-level perspective.

So, who here has the knowledge and the energy to run the numbers on whether this is more than just plausible and actually possible? I wish I had the former because I certainly have the latter and enjoyed the book--the plot, the technical details, and the writing style--enough to want other people also to enjoy it. Maybe Randall Munroe will give it a shot, although it is a bit non-absurd for his usual taste.

By the way, let's give the author one deus ex machina point for how he solved the final problem that his characters faced. Does he get a negative deus ex machina point for how he created the first problem that they faced and thus balance it out or do both problems and solutions have positive valence when counting the dei ex machinis?

Comment Re:It not very hard (Score 1) 167

I thought their current business model was to charge everyone $5 per month, including non-subscribers. At least that's what my credit card statement and numerous online forum posts seem to indicate. Their customer service apparently also sucks, as they refuse to answer when you e-mail or call to discuss the fraudulent charges. They could probably become more profitable if they started earning money instead of stealing it.

Comment Re:I'm confused (Score 1) 293

At least the editors, who are surely knowledgeable enough about technology to have a basic grasp on what a hydrogen-oxygen fuel cell is, likely from growing up reading about the Space Shuttle and thinking decades ahead about how cool it will be to power everything with such an amazing device, were able to catch this absurd inaccuracy and correct it before publishing this idiotic submission. mean to tell me that it was only all of the readers of Slashdot who caught that, not the editors? How did that happen?

Comment Re:What's happened to Slashdot? (Score 1) 151

The number of comments just proves that number of people who read about this in mainstream media several days ago when it was trending on Facebook but who had to wait for Slashdot to catch up to the trend before they could say anything about it that someone else might read.

The fact that it is trending on Facebook this week proves something else, which is that most people think the Aral Sea is a big circle as shown on most world maps and globes and had no idea that the Soviets had diverted its main sources, leading to its shrinkage, about 50 years ago. I admit that I suffered the same ignorance, although I learned about this a few years ago before it was cool and I suspect that I am not the only one whose sole surprise from this story is that it is so popular to talk about this week all the sudden.

The use of the term "inland lake" in the summary proves that no nerds were even involved in getting this article onto Slashdot's front page. A real nerd would not distinguish between inland lakes and all of those lakes in the middle of the ocean.

Comment Re:Blaming the cables? (Score 1) 476

My experience with solid-state batteries differs significantly from yours. Maybe it's just colder here in North Dakota. :)

Also, the Prius's heater uses engine coolant. It apparently has an auxiliary electric heat source and water pump to keep the cabin heated when the gasoline engine is shut off, but if they put the car together in a remotely sane manner that should result in redundancy rather than an additional point of failure. If the batteries or the gas engine fails you in the Prius, you still should not freeze to death.

In a Tesla, though, if the batteries fail you then you will freeze to death. While the same is true for the fuel line and pump on a gasoline car or, much greater risk because of fuel gelling, on a diesel car, I have not personally witnessed a properly maintained gasoline car that started and reached operating temperature fail because of fuel delivery issues, in a climate where -40C happens at least annually and for roughly three consecutive months each year the temperature does not exceed -10C on more than a small handful of days.

And that's what I mean about the Tesla being unproven. We have a century of gasoline and diesel engine experience so we know how to keep them working in extreme cold and the risk of problems is a known quantity. We also have a solid understanding of how to survive in the event of various problems that can arise. (As an example, if you are stuck in the snow but the engine is running, you ensure that the exhaust is clear so it can escape to atmosphere and then you stay in the car for warmth and safety.) For a hybrid like the Prius, the risks should be both similar to those in a gas car and also mitigated by intelligent engineering of redundant systems. They are still uncommon here, but that is likely more because they have low ground clearance than because they are hybrid. For a purely electric car, though, we have no experience keeping them running in extreme cold and the risk of problems is an unknown quantity. We also do not have a good understanding of how to survive if a problem arises. What do you do if you are stranded in cold weather by a dead battery and help will not arrive until morning?

Everything I have identified as a risk of electric cars can surely be quantified and likely be mitigated. But with gas cars we have a century of experience to draw on. It will be a long time before the same can be said for electric cars. And during that time, I will let people in populated areas where help or alternative transportation is within a 5-minute walk at all times learn and fix the problems before I incur the risk of a frozen battery leading to my own freezing to death.

Comment Re:Blaming the cables? (Score 1) 476

I have found that batteries fare very poorly in general in the cold. That includes the starting battery on my car, the battery in my phone, the battery in my camera, and every other battery of any chemistry that I have exposed to the cold. The difference is that an internal combustion engine warms up as you get farther down the road, reducing the risk of failure due to the cold. In other words, cold-related failure of a gasoline car is most likely to occur in your driveway where you can walk inside and survive. It seems that electric cars increase the risk of failure as you drive away in the cold. People who become stranded in a gasoline powered car with adequate fuel and do the right thing by staying with the car tend to survive. Electric cars that accomplish the same results are certainly possible, but not yet proven.

Comment Re:Blaming the cables? (Score 1) 476

This has always been my concern with electric cars. Batteries do not work well in the cold. I live in the part of the USA where Norwegians settled because it reminded them of home. Except we were having a heat wave at the time, and now it's colder. A warm gasoline or diesel engine will generally keep running no matter how cold it gets, so by the time you are any distance from the safety of your home, you have the safety of a running car with a working heater until you run out of fuel (assuming you have not filled with #2 diesel, which turns to gel in the cold). An electric car that relies entirely on batteries will get you just far enough from home to be in danger when the batteries have, due to temperature, become unable to move the car or to provide heat for the occupants.

I think an electric car would be great for the summer months. Maybe they should market electric motorcycles. But in the winter, living in a rural area where the ambient daytime temperatures are often -15C and occasionally -45C or worse, electric vehicles have a long battle to prove that they are as safe as their gasoline and diesel powered counterparts.

Comment Re:Slashdot in Greek (Score 3, Insightful) 42

To those interested in the implementation of programming languages, it is immediately apparent that this is a fundamental change in the compiler behind the GNU Guile system which implements the Scheme programming language, inasmuch as it now has a virtual machine based on the register model instead of the implied stack model, along with an intermediate language in its compilation path that is based on continuation-passing style.

I think that the lesson here is for everyone: There are many segments of nerd culture, and it is very unlikely that any randomly-selected Slashdot reader understands and appreciates all of those segments. For example, the earlier headline today "Why Transivity Violations Can Be Rational" has no meaning to many readers, even after the title was corrected to spell transitivity correctly. After reading a little about that topic, I see that it is an area of of obvious interest to many nerds.

That being said, there are plenty of topics Slashdot poorly reports on which are not of interest to any segment of nerd culture, at least not beyond the overlap between nerd culture and the mainstream news where we already read the same information three days earlier except through the words of a literate, competent reporter with real editing before it hit the press.

Comment Re:The farmer's recourse is to sue to sell (Score 1) 579

Assuming that there are negative effects of the current patent system in terms of seeds, there is still another side to the coin. Without patent protection, would Monsanto have developed Roundup Ready (TM) soybean seeds? Or, for that matter, Roundup (TM) herbicide? Without these complementary items, soybean production would be much lower. (Due to decreased production by using other means of weed control and/or increased cost of weed control.) Maybe both products would exist without the seeds being protected by patent law, but if, on average, the total production is increased by the availability of such protections, they give society a net gain.

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