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Comment Re:Redirecting (Score 5, Funny) 188 188 is clearly unresponsible to DMCA takedown efforts; legal approaches simply won't suffice. I recommend that Universal Pictures launch a coordinated effort hack into it using as many computers as possible, gain root access, and write over its hard drive.

Comment Re:Interesting; likely more limited than advertise (Score 2) 82 82

That actually doesn't sound that bad:

"For example both alcohol (ethanol) and water produce large peaks on an IR spectrum and from the video it would seem that the user provides some background data on what the sample is via the app, so that saves a lot of work. It would be easy for the algorithm to say, 'the user says this is drink and I can see that about 40 per cent of the total spectrum is ethanol so I should give a reading of alcoholic beverage with 40 per cent alcohol content'. Or 'this is a plant and 70 per cent of the spectrum is water so it must be 70 per cent hydrated'. This could also be done with total sugar content for common sugars such as sucrose and fructose," he said.

"Similarly, it would be possible to get a spectrum good enough to recognise something like fruit or Tylenol and then send back generic data (easily found via Google)

That would hardly be useless. I presume that the person knows whether what they're looking at is a fruit or an alcoholic beverage. It's not a big deal to ask the user to do whatever degree of categorization that they can to help it out. And being able to pick out common drugs? Definitely not useless.

Comment Re:Interesting; likely more limited than advertise (Score 1) 82 82

Thanks for your insights. Still trying to decide whether something like this should go on my wish list ;) (see above for my potential uses).

How accurate, exactly, do you think such a device could be? Obviously it's not going to be pulling out the sort of precision of a professional spectrometer. But you mention, for example, being able to identify the signatures of herbicides and pesticides. Do you mean, for example, "This contains imidacloprid", or more like, "This contains a nicotinoid of some variety"?

How useful do you think it could be on identifying mineral species - say, distinguishing between different zeolites? Or, back to food, if given, say, a mango, to get readings of, say, water, sugar (in general, or specific sugars), fat (in general, or specific categories of fats, or specific fats), protein (in general, or specific categories of proteins, or specific common protiens... obviously it's not going to be able to pull out 5 ppb of Some-Complex-Unique-Protein), common vitamins (generally found in dozens of ppm quantity - some more, some less), minerals (likewise), etc?

Comment Re:Smartphone as powerful as 80's supercomputer (Score 2) 82 82

Smartphones are still drastically slower than individual PCs, let alone cloud services.

I know they're overstating the case, and that it's a near-IR spectrometer, not a mass spectrometer. That said, I still like the general concept. Does anyone know whether near-IR spectroscopy can be used for identifying mineral species (for example, between different types of zeolites and the like)? I love rock hunting but many species have similar visual appearances.

And even on the food standpoint I find it interesting... I'm a tropical plant nut, and lots of people I know over on the forum breed unusual varieties of common fruits as well as rare fruits (some of which don't even have scientific names). It's be neat to be able to get a basic compositional profile - no, not "this fruit contains X ppb of this gigantic-complex-unique-protein", but just the major constituents. It'd help, for example, the mango breeders to know if their fruits are compositionally different from the fruit of the parent cultivar.

Comment Re:Finger and Sand (Score 4, Funny) 617 617

I've cut a plastic binding with a sharp rock. I didn't knap it myself, it was naturally sharp, but... I don't think it gets much more old school than that ;) Unless there's someone here who made productive use of throwing their own excrement in a production environment.

Comment Re:Futile search? (Score 1) 208 208

I agree with most of what you wrote. But I have the most interest in sample returns because we have such vastly greater analysis capabilities here on Earth than we could ever send on a mission - especially a lower budget mission. And by leaving off surface science hardware, you save development costs and a significant amount of spacecraft mass.

Also, capturing samples, you don't have to land to have a low impact velocity. If you reach Saturn via ion propulsion then you could at little cost enter a Molniya-like orbit over the plumes so that the spacecraft would be nearly stationary relative to the particles during collection. Enceladus orbits are slow to begin with due to the low gravity (0,114m/s versus Earth's 9,81), and by positioning a high apogee or near-apogee over the plumes it might even be possible to collect jet material at lower impact velocity than one could from the ground. Enceladus's gravity would contribute to decelerating the particles and, if desired, one could have the probe's ascent phase over the plumes (rather than the apogee) for further relative velocity reduction. Impact velocity would be not much more than the random variation between the particles' individual trajectories, and some would impact with near-zero velocity. Combined with a carbon aerogel collector (much less dense than the silica aerogel used by Stardust), I seriously doubt you'd do any damage at all to what's collected - most particles shouldn't even melt.

Every added system is added mass and development cost; landers don't usually come cheap, even on a low-gravity body like Enceladus. And dropping a lander near potentially unpredictable fissure geysers carries a risk. So I personally tend to favor spaceborne collection. That said, one would probably learn more from the surface, and you'd be able to sample surface ices as well, not just plumes.

Comment Re:certified materials (Score 3) 220 220

You think having the part designed to handle five times the load it actually experienced to not be "with sufficient margin"? How much of a margin do you want them to put, 100x?

RTFA. They were doing statistical-sampling quality control testing of struts. The problem was that most of them were just fine, but there were a very small number which were totally defective and broke at a tiny fraction of their rated value. And no, SpaceX did not make the parts, it was an outside supplier. And yes, SpaceX A) will now be testing 100% of them, and B) is ditching the supplier.

Comment Re:Transparency (Score 1) 220 220

It's not just about the cost of a failed launch, there's also a huge cost to a company's reputation if a rocket fails. And to their schedule.

Out of curiosity, is there any lightweight way to sense how close a part is to failure *in use*? I mean, finding defects on the ground is great, no question. But what if something would doom a mission not due to a part having a manufacturing defect, but due to an oversight somewhere in the rocket design process, or assembly, or transportation, or launch setup, or unexpected weather conditions, or whatnot? It seems to me it could be a massive boost to launch reliability if one knew that a part was about to fail - for example, in this case, the computers could automatically have throttled back to the rocket to reduce stresses, at the cost of expending more propellant, and possibly been able to salvage the mission. And then the problem could be remedied for future missions, without having to have a launch failure first.

To pick a random, for example, would there potentially be a change in resistance or capacitance or other electrical properties when a strut nears its breaking point?

Obviously, though, if adding sensing hardware would add a high weight or cost penalty, that would be unrealistic.

Comment Re:Futile search? (Score 1) 208 208

Funny ;) But the main point is that its surface is high radiation and very oxidizing; and as far as we know there's no liquids anywhere on Mars except for possible transients or extremely perchlorate-rich brines (aka, something you'd use to sterilize a rock of life).

On the other hand, subsurface water oceans are common elsewhere in the solar system, and colder bodies are known and/or theorized to have a wide range of alternative liquids.

Comment Re:Holy Jebus (Score 5, Interesting) 220 220

Also, maybe it's just because I've never worked in that industry before, maybe it's common practice in rocketry, but is anyone else impressed with the use of sound triangulation to figure out which part broke? I've never heard of that being done before.

Sad that the Falcon Heavy won't be launched until next spring, I've been really looking forward to that. Oh well...

Do not underestimate the value of print statements for debugging.