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Comment Re: Great idea... But there is a problem... (Score 1) 287

They didn't die after a few minutes - they lasted for 1-2 hours. And they didn't cost a billion dollars, they were built on the cheap. The Soviets launched almost all of their Venus missions in pairs because they considered it likely that something would blow up or fail at some point along the way - not a rare situation, a number of their Venus missions never even left Earth orbit, and some didn't even get that far ;). But of missions that actually got to Venus, they had great success, and even had one mission "rescued" by Venus (they designed it to parachute down, but the parachute broke - but the atmosphere slowed the fall so much that it survived the impact anyway).

For exploring Venus, if you're wanting PR, the Vega approach is the right one - aerobots, optionally paired with sondes. Aerial vehicles can fly for long periods of time studying the planet, and there's a number of exciting missions related to this being worked on (just waiting for funding). As for surface lifespans, they don't have to be limited. There's work on probes designed to "run hot" so that they don't need any (or only minimal) cooling, and there's also work on probes designed to lift off (bellows balloon) to a cooler layer of the atmosphere (to have any length of time to examine / process samples, cool down, etc) before re-descending any number of times. If you're only talking something with a ~2 hour lifespan on the surface and nothing else, you're talking something cheap, Discovery or at most New Frontiers class - not Flagship.

The main thing that's held everything back is that NASA almost never funds anything related to Venus. The last dedicated NASA mission to Venus (not counting flybies to other destinations that used Venus as a gravitational assist) was the Magellan probe, nearly three decades ago. And that came a decade after the previous NASA mission to Venus. Easiest planet to get to, and they almost never fund missions to study it. It's embarrassing.

Comment Re:Echo-chamber fake news (Score 2) 297

There were a lot of contributing factors, but yes, this sadly was one. The Thiokol engineers were against launch, but they failed to make a sufficient case as to why exactly they felt the O-rings were unsafe (there actually was a Thiokol document showing that not only was O-ring failure high at low temperatures but that the second O-ring ceased to be redundant - but they didn't have the document available to them). The Shuttle program managers were getting mad at them for insisting on delays due to the low temperatures without being able to back it up (one of them said something along the lines of "My god, Thiokol - when do you want me to launch, April?") and eventually the Thiokol management dropped their objections (even though the engineers were still strongly against launch). The engineers all gathered round to watch the launch on TV, thinking it was going to explode on the pad. When it lifted off they all breathed a sigh of relief, only to have it dashed during the explosion.

Comment Re:Echo-chamber fake news (Score 5, Informative) 297

Really, I have to give them credit where credit is due: by repeatedly pointing out errors (however trivial) out of the tens of thousands of news stories that are published every day, they've managed to get their supporters to the point where they'll trust a new story on www.siteiveneverheardofbefore.com/newishstuff/hillaryclintonpedophilering.html more than they will an actual newspaper. It's a real masterstroke in terms of controlling the narrative. "Anything negative you hear about me, it's fake, because there exist cases where newspapers have made errors, and we've selectively presented you only with those cases to create a narrative for you that newspapers are packed full of fakery." Not just newspapers - fact checkers, peer-reviewed articles, even official government statistics - all fake, because they've been presented with every case people can get their hands of of error, without the balancing context of the 10000x more that wasn't in error.

In the words of XKCD: "Dear God, I would like to file a bug report". ;)

It's the same thing that contributed to the Challenger explosion. They had a nice clean graph in front of them that plotted O-ring failures vs. temperature. There was no clear trend visible on the graph. The problem was that they omitted the successes, the cases where there were no O-ring failures. Here's what it looked like with that added in. All of the sudden there's a very clear trend of failure increasing at low temperatures - in fact, every low temperature launch had had O-ring failures, while very few high-temperature launches had. By being selective in what data you present (accidentally in that case, on purpose in the present case), you can get people to believe precisely the opposite of what is true.

Comment Re:This is an OS (Score 1) 131

I hate defending microsoft, however the problem is most users won't install an update. even today the average user is to stupid to understand how and why they should update.

Look at ios and Mac OS . iOS achieves something like an 75% updates installed within 3 months of it being released.
versus
andriod or windows xp/7 which gets 25% of updates installed in 6 months.

Windows 10 is microsofts attempt at getting updates installed in a timely fashion. the issue becomes they are also using it to make major changes to the whole thing at the same time. The update vs upgrade mechanism is the same and so major oS updates are shoved through which break stuff.

Lastly programmers themselves have a nasty habit of targeting the old systems first which is what breaks. even with windows 7 using win32 installers should be a big no no. yet it is a common thing. (apple avoids that issue by not needing installers, instead they drag the app(folder) to the program folder and run it. Apple does use a package manager for installing things like drivers though.

Comment Re: Great idea... But there is a problem... (Score 1) 287

Anyone who can say "only 6000 m/s" with a straight face when talking about post-launch maneuvers has never worked with rocket mass budgets. ;) For a single stage, 6000 m/s with a 340s isp and 0.08 inert mass ratio is an over 10:1 scaling factor (aka, for every 10 kg you launch to LEO you get 1kg payload to your destination). Just 3000 m/s is a nearly 3:1 ratio.

Comment Re: Great idea... But there is a problem... (Score 1) 287

Probably better to get some kind of cloud city working on Earth before attempting to go trans-solar-system with the concept.

That would indeed be part of the development process. It's harder on Earth, mind you - a Landis habitat has to be inflated with heliox on Earth, which is much more expensive and permeation-prone. But such a habitat absolutely can be tested on Earth.

By the altitude Venus' atmosphere is more dense than Earth's, it's also highly corrosive.

The sulfuric acid is quite overstated in the popular imagination. It's more like a bad smog (or more accurately, vog) - several to several dozen milligrams per cubic meter, as noted below (also as noted below, OSHA allows people to breathe up to 1mg/m^3 for an entire 8-hour shift). It's much more of a resource than a problem; design work would be simpler if it were denser, not sparser. Material compatibility is easier to ensure (via fluoropolymers) than the scrubber design aspects are; you have to have high mass flow rates because the sulfuric acid is so sparse.

(That said, there was some - disputed - evidence from Vega that there may sometimes be "rain" on Venus. If that's correct, that'd be quite the blessing for resource collection. It's sad how we don't even know such basics as "does it rain on Venus?" at present)

Jupiter is a little too active for my taste, but perhaps Neptune or Uranus might have some attractive latitudes at which to float a city, assuming you bring your own power sources and don't rely on the sun.

The gas and ice giants are tough. They're very, very far, exceedingly hard to get out of, and because they're predominantly hydrogen (80-96%), the Landis design is right out (you can't live in a spacious envelope, you're stuck in a gondola); the envelope has to be hot hydrogen (heated with a lot of energy, because you lose it quickly on those scales). The gas and ice giants also have the wrong ratios of temperature to pressure - too much pressure relative to temperature. Plus, much less diverse gaseous mineral resources, and (effectively) no surface mineral resources at all. And of course as you note, little light. Venus is far better in virtually every respect. Its right next door, the easiest planet to get to, a great location from an orbital dynamics perspective, and it has everything.

Comment Your textbook is stupid and the author should be f (Score 1) 211

Your textbook is pretty dumb. it's just as much linux as your wireless router is probably linux - no, it's even more so linux than that. just because you're not using X doesnt make it non-linux - or then me and my brothers first linux installations weren't linux too(they were).

Android most definitely is Linux. you cannot separate the two. even if you're not using ndk and using only dalvik/art, you're still using linux threads and a bunch of other linux things almost directly.

you COULD maybe run "android apps" inside another operating system, but Android as in lets say android 5.0 or whatever is definitely linux and a lot of how the apps and systems on it work bind directly to the linux kernel all the way to the way process security works. furthermore you can just run linux binaries too, provided that the linux installation of course on the phone has everything that binary needs in order to run.

anyways, if your android textbook says it's not linux, then people who learn by it will probably never even think that it is linux and thus can just wonder with amazement at what some apps do while they can never make their apps do the same.

did the textbook also tell you that asynctasks are somehow magical without showing you the source to them, disproving them as magical and making them look like a dumb waste of space?

Comment Re:DuckDuckGo (Score 1) 98

the idea is to demote links to such search engines.

the companies who provide this service to the media companies are lazy as fuck, so what they care is just sending a few per week to the same sites that are on the first page of results. they bill by the amounts served and bill high and just do it enough.

case in point how it works on youtube - you can find common movies and tv shows from major networks if you just bother to type in the names. the folks SELLING this service to the media companies DO NOT EVEN BOTHER with that 99% of the time, instead they just trust youtubes content id.

seriously, if I can find top gear on youtube, why can't the folks selling the content protection to bbc cant? because they are lazy fucks.

Comment Re:If Apple built a Hololens we'd never hear about (Score 1) 103

But they want developers on board of it already.
Despite the developers not having a market or users to sell to!

2019 is just as good as saying "in the future! with memristors!".

the development suite for hololens 1 is THREE THOUSAND BUCKS. THREE FUCKING THOUSAND BUCKS.

or 5000 bucks if you want warranty and basic mdm that you would get for free on a 99 bucks android phone.

2019 is just as same as saying they're just waiting for some prices to come down. but it makes it almost totally utterly pointless to buy the devkit for 3000 bucks now, given that an user version of the same thing is 2 years away(at least) and might not have _anything_ to do with the devkit!

Comment Re: Great idea... But there is a problem... (Score 1) 287

I'm with a group called Venus Labs; we'll have our first book out later this year. :) Materials compatibility is a big topic therein. Thankfully, there are a lot of polymers that have good resistance to Venus's environmental conditions (particularly fluoropolymers, although minimizing coating fluorine content is important for ISRU because hydrogen fluoride is a lot less common than hydrogen chloride and sulfuric acid - so for example PCTFE or PVF would be preferable to, for an example, FEP). The sulfuric acid mist isn't actually very concentrated from a particle density perspective - visibility is a couple kilometers. The mist is a couple to several dozen grams per cubic meter, depending on the altitude, latitude, time, etc (by comparison, OSHA allows people to breathe up to 1 mg/m for an 8-hour work shift). But it is concentrated from a molar perspective - on Earth, H2SO4 mists self-dilute with atmospheric water vapour.

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