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Comment Re:Con? (Score 2) 404

They cheated if they broke the rules. Without knowing in details what the rules were, we can't say whether they cheated.

However we do know that a judge who knew in detail what the rules were required them to return the money. This being a civil case, we don't know if what they did was criminally illegal.

Comment Con? (Score 1) 404

Con:
Persuade (someone) to do or believe something by lying to them.
A confidence trick ... is an attempt to defraud a person or group after first gaining their confidence, used in the classical sense of trust.

I don't see where he lied, so I think the word is misapplied. The second definition comes a little bit closer, but casinos are very much aware that gamblers are adversaries, not allies.

Comment Making America great again (Score 4, Insightful) 129

What do people mean when they say "make America great again"? My understanding is that they want a USA which is making new innovative industries, employing lots of people in the USA with high paying jobs, and making profit in the process (the more the better.) Elon Musk is the poster child for doing all of those things - yet many people crying "Make America great again" are trying to tear him down. The kindest explanation is that they are so blinded by ideology that they can't think straight.

Comment One bit doesn't make sense (Score 2) 101

"This would give SpaceX three landing pads and the ability to bring back all three Falcon Heavy boosters to land while also retaining the option to land one or two on drone ships in the Atlantic Ocean."

I can imagine scenarios where you'd want to land zero, one or three boosters on drone ships. I can't imagine any scenario where it makes sense to land two boosters on drone ships. One way would be to have the center booster and one side booster landing at sea - but if one side booster can return to landing site, so can the other (and landing on land is both cheaper and safer if you can do it.) The other way is to land both side boosters at sea but return the center booster to land - but the center booster is always going to be much harder to return to land, as it burns longer and so is higher velocity and further down range when it has finished boosting.

Comment Oversold (Score 3, Interesting) 148

Here's the most relevant bit:

The team was able to compress small flakes of graphene using a combination of heat and pressure. This process produced a strong, stable structure whose form resembles that of some corals and microscopic creatures called diatoms. These shapes, which have an enormous surface area in proportion to their volume, proved to be remarkably strong. “Once we created these 3-D structures, we wanted to see what’s the limit — what’s the strongest possible material we can produce,” says Qin. To do that, they created a variety of 3-D models and then subjected them to various tests. In computational simulations, which mimic the loading conditions in the tensile and compression tests performed in a tensile loading machine, “one of our samples has 5 percent the density of steel, but 10 times the strength,” Qin says.

The video is about testing 3D plastic models. Exactly what they have achieved is unclear to me. Do they have plastic in a configuration 10 times the strength of steel? Did they 3D print in steel, but didn't show it in the video? Did they extrapolate from a plastic model to say that if they'd made it of steel it would be 10 times the strength of steel? Did they use a computer model to say that if they could make the optimal graphine configuration it would be 10 times strength of steel?

Comment Re:Would be nice... (Score 1) 75

They then began loading cold helium. Had the oxygen stayed liquid, it would have squeezed out (expected behavior). Rather, the oxygen wasn't able to seep out fast enough, and the increasing pressure caused some of it to solidify, blocking the escape of oxygen from the CF.

So if I understand the logic of these tanks correctly: The He tank necessarily is at high pressure relative to the LOX tank, as it will be pressurizing the much larger LOX tank as it empties. CF is strong enough to hold the tank together against this pressure, but can't prevent seepage through it. The aluminium layer prevents gas escape, but contributes little to the structural strength of the tank - hence when filled, it expands like a balloon until the CF prevents further expansion, which necessarily compresses the CF. (Because LOX will seep through the CF to contact the inner layer, the inner layer has to be something which plays nicely with LOX, and aluminium does so, but this is probably a happy coincidence rather than a reason why aluminium was chosen.)

An alternative fix would be add an outer aluminium layer (which could be very thin) to prevent LOX getting into the CF. However, the integrity of this outer layer would be critical - if it leaked a little LOX in, it would impede its exit when the tank pressurized, which would likely cause explosive failure.

Comment Ad servers at fault? (Score 4, Interesting) 137

If you are a web advertising company, why should you ever allow advertising clients to include arbitrary Javascript in their ads? Could you not provide a Javascript library of your own to do the legitimate things ad Javascript might do, and only allow advertising clients to use simple calls into your library?

I'm not knowledgeable about Javascript or web advertising - these are genuine questions, not rhetorical ones.

Comment Re:about time (Score 2) 64

The connection I see is that you can use it to deorbit satellites at end of life, provided the satellite was was equipped with a deployable tether. Once the tether is deployed, the deorbiting process is completely passive and automatic. This doesn't help at all with the junk that is already present however. Perhaps you could attach tethers to large existing space junk but matching orbits with them to do this would be expensive.

Comment My plan (Score 1) 64

I thought of a similar plan some years ago: make a balloon out of some very thin light material, such that when inflated, it is very much larger than the satellite. When the satellite is at end of life, inflate the balloon (takes very little gas, as we're in a vacuum.) This greatly increases the drag against the very thin outer atmosphere of the earth. (The balloon will get punctured eventually by other space junk. Without testing, I don't know if it would deflate to smaller cross-section if this occurred. If it would deflate, we'd need countermeasures, perhaps a balloon material which hardens on UV exposure, or spraying some adhesive into the freshly inflated balloon, either way so that it has structural strength to hold shape without gas pressure.)

This is similar to the Japanese plan in that it is a lightweight device you attach to your satellite, which deploys and end of life to speed up deorbiting. In both cases you could put the deorbit device on a dead man's switch, so that it will autodeploy should the satellite fail. I don't know which device would be more effective, except that my device is much more altitude sensitive than the Japanese tether, and that these people are smart enough to think of my balloon but chose to develop the tether.

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