I think it's pretty amazing that spacecraft can survive at all out there, given the sort of particles flying around - individual cosmic rays with the energy of fast-pitch baseballs. Thankfully, particles with such high energy have tiny cross sections (they prefer to move through matter rather than interact with it), and when they do hit something and create a shower of particles, most of the progeny is likewise super-high energy and will most likely just move through whatever it's in.

It's more interesting when they strike the atmosphere - each collision creates a new shower of other high energy particles, more and more, spreading out the energy as they descend. In the end, detectors on the surface over an area of dozens of square kilometers simultaneously pick up different pieces of the same cascade kicked off by a single cosmic ray collision.

No, fines for violating export laws.

Being slapped with massive fines is usually pretty good motivation for a company. And given that the US spends nearly half of the world's total military spending, and the EU a good chunk of the rest, simply "hopping overseas" and choosing to serve other markets isn't exactly the smartest of plans, financially.

It's idiodic for a company to wilfully risk sales of hundreds of thousands of units per year to NATO to sell a couple hundred units to Russia. Russia's economy is barely bigger than Canada's. And less than 80% the size of Brazil's.

You could start by reading more than the first paragraph.

1) They don't have "zero" capability, but they have way too little - only a few hundred modern imagers.

2) They have tried to buy them off ebay before. And it led to arrests. It's illegal to export military-grade night vision equipment without a license, and apparently sites like ebay are well monitored for potential violations.

Yeah, but they "cheat" a lot - for example, Belarus has made a mint serving as a reshipping platform for European goods. And for some reason they left Iceland off their list even though we supported the sanctions against them. Still, it's caused major food price inflation (unsurprisingly). Seems kind of a weird way to punish Europe, it seems obvious it's going to have a lot more effect at home than abroad - Russia's trade in food goods with Europe makes up far more of its imports than Europe's trade in food goods with Russia makes up of its exports. But I guess they didn't have a lot of options for "retaliation". I mean, Gazprom is already nearly going broke as it is, turning off the spigots would have rapidly ensured that it did. Oil and gas make up half of their government budget and 2/3rds of their exports - it'd sure punish Europe, but it'd also be economic suicide.

I think they're really hoping that the sanctions will just expire and they'll be able to go back to raking in western capital again. Because if they don't expire, barring some huge unexpected oil price surge, those reserve funds are going to dry up. They expect it to be down to under $40B by the end of this year. What they're going to do when it runs out, I have no clue. They need dollars and euros to buy the goods that their undersized industrial sector can't manufacture. China's a help but not a solution; they don't have the lending power of the US or EU to begin with, and their goal seems to be more exploiting Russia over the situation than offering friendly aid. For example, they got Russia to agree to the cutthroat rates on the proposed "Power Of Siberia" pipeline that they'd been trying to get for years and to let them own greater than 50% stakes on fields inside Russia. They got Russia to sell them their most advanced air defense system despite the objections of the defense industry over concerns that China would do what they always do with new technology - reverse engineer it and then produce it domestically. But who else are they going to turn to? China's basically becoming Russia's "loan shark". And at the end of the day, if it came down to it and China had to chose between the Russian market and the 20-fold larger market of the US and EU? It's not even a contest.

I figured they'd tackle something more ambitious than that with their drone offerings - a drone that (barring instructions to do otherwise) follows you around whatever you're doing and keeps the camera on you, trying to get the most epic shots. E.g., you bungee jump off a bridge, it races you to the bottom, keeping whatever distance and filming style you told it to.

But maybe it's just another remote control drone.

So you mean get rid of wide-character encodings and only use UTF-8 where unicode characters are needed? I agree. :)

But that's the point. If it slams into an immobile object of course. But we're not talking about anything slamming into an immobile object. From the perspective of a molecule in the gas stream, it's going about the same speed as its neighbors. It's quite cool.

As for the boundary region, even at the "pinched" funnel outlet one could be talking dozens of kilometers here. A dozen kilometers between going from zero velocity and 25 kilometers per second is roughly the same as a dozen meters between going from zero velocity and 25 meters per second. Aka, a virtually insignificant gradient.

UTF-8 is an encoding of unicode, so I'm totally not getting your "Actually I think "Unicode strings" should be avoided completely."

I like that idea. You're right, it should be pretty efficient to implement, regardless of the string's backend encoding. And the value represented by the iterator will, by nature of being implemented as a pointer to a certain part in the string, be able to point to a glyph of arbitrary length (unlike a getter function with a fixed-length return type). Being an iterator it'll fit into all standard c++ libraries that take iterators.

It would be nice to have it be a random-access iterator so that you can jump to an arbitrary offset. There's a lot of optimizations they could do internally to help facilitate that. But obviously you still want to let programmers choose - by some means or another - whether they want such unicode optimizations (or unicode iteration, or so forth). Because while the overhead they'd impose wouldn't be huge, there still would be overhead.

We have to have something, though. Not everybody writes in English.

Except wait - we've got a phase change from gas to plasma in there, which almost certainly breaks their calculations badly.

Again, no, you don't. All of the particles are moving in the same direction. They're not hot. They're not slamming into each other and kicking electrons off.

Do you think if you had a spacecraft moving at 25.4 kilometers per second it would be plasma too?

First off, you're misusing temperature. You don't call it heat if all of the particles are moving in the same direction and unionized, you just call it "wind". It only becomes heat if that windstream suddenly slams into a non-moving solid surface and becomes instantly thermalized (but of course even then that would be a very short-lived event as it would correspond with a pressure rise and the deflection of the stream behind the high-pressure zone). Additionally, nor would that be the windspeed touching the surface as, obviously, wind forms boundary layers.

Secondly, hundreds of km/s from Venus escape to Mars intercept? That doesn't at all correspond to any delta-V chart I've ever seen.

And it's important for new programmers to learn them - more important than learning syntax.

  For C++ for example I'd warn about classes containing pointer member variables with implicitly-defined assignment operators / copy constructors. You have Foo a and Foo b, where Foobar has a member variable "int* bar". So the newbie does "a.bar = new int[100];" then later "b = a;" then later b goes out of scope, then they try to use a.bar and the program crashes. Seems to be a very common C++ newbie mistake. Eventually they learn to see pointers in class definitions as having big "DANGER" signs over them calling their attention, and/or rely on smart pointers.

Any others that people can think of that are common?

Oh, here's one more: iterator invalidation. A newbie who's not warned about this in advance will likely get bitten by it several times before the point gets driven into their head: "if you're using a class to manage memory for you, it's going to manage memory for you, including moving things around as needed."

Yep, they have been UTF-16 for a long time. And Unicode has been widely broken for a long time. It's not a coincidence.

Someone on StackExchange did some tests last year, adding in 4-byte unicode characters in common applications and seeing how they behaved. The results were really bad:

Opera has problem with editing them (delete required 2 presses on backspace)
        Notepad can't deal with them correctly (delete required 2 presses on backspace)
        File names editing in Window dialogs in broken (delete required 2 presses on backspace)
        All QT3 applications can't deal with them - show two empty squares instead of one symbol.
        Python encodes such characters incorrectly when used directly u'X'!=unicode('X','utf-16') on some platforms when X in character outside of BMP.
        Python 2.5 unicodedata fails to get properties on such characters when python compiled with UTF-16 Unicode strings.
        StackOverflow seems to remove these characters from the text if edited directly in as Unicode characters (these characters are shown using HTML Unicode escapes).
        WinForms TextBox may generate invalid string when limited with MaxLength.

I've had more than my share of these sort of experiences too.

UTF-16 is dangerous, and should be phased out as much as possible. Where absolutely needed for performance reasons, it should be an internal representation only, hidden from the developer as much as possible. In particular, "length" functions should return the actual string length in characters, not code units; indexing functions should take character offsets; not code unit offsets; and returned "single characters" exposed to the developer should be of a format capable of handling multi-code-unit glyphs. Anything involving working with actual singular UTF-16 code units should only be available as a "for advanced users only, use at your own risk" functionality.

. So basically you'd need to impart almost 6x as much energy (36x as much speed) to get to Mars as to just escape Venus

Yes, the velocity would need to be tens of kilometers per second. But really, what's the limiting factor here? Certainly not skin drag, when you're talking something on the necessary scale here. Viscosity losses, radiating the energy away to space as heat? The energy can't effectively radiate away as heat, that's why the funnel is there, to reflect IR while transmitting visible light from the sun. There's not many options for the gas to lose energy except to accelerate.

Basically that "negligible drag" would be the only thing providing a supporting force to the funnel.

Negligible from a systems perspective. But from the perspective of the funnel, it's tremendous force. The mass of the funnel is insignificant compared to the mass of the rising gas when you're talking about a megastructure.

I wonder though what might happen if you directed the CO2 to Venus's L4 or L5 points? Could you build up sufficient mass to create a stable bubble of CO2

That would be.... unusual. What would you call that, a "Gas Dwarf"? I really have no clue how much you could have persist stably there, but I'd be really curious to know. It'd be particularly strange if you could make it out of a combination of gasses that are breathable - aka, limiting the CO2 levels, O2 from CO2, and any mix of Venusian/Jovian N2, Ar, and He as buffer gasses as needed. If the water vapor levels were low then there would be little in terms of cloud cover to reflect light. Earth's atmosphere absorbs about 1/3rd of the sun's energy, so with two passes through it'd absorb about half; at Venus's distance it'd probably be a pretty comfortable temperature. Gravity would be tiny. Obviously not long-term stable due to the solar wind, and high radiation, unless you artificially create a miniature magnetosphere. But in the short term...?

That would be so weird to be floating "midair" in a temperate breathable environment with no land anywhere.