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Comment Barely ahead (Score 1) 93

Saying that the Chinese are ahead of SpaceX in heavy lifters depends on how you measure "ahead". Although it has never flown in this configuration, the Falcon 9 Full Thrust in expendable configuration (no landing legs or grid fins, and no propellant reserved for landing) is a heavy-class lifter. It's only 22.8T to LEO vs. the Long March 5's 25T, and the difference in GTO capacity is much more pronounced (8.3T for F9E, 14T for LM5, probably because of the LM5's LH2/LOX upper stage), but SpaceX does already have a heavy lifter if they want it to be that. Falcon Heavy, in expendable configuration, is vastly more powerful still; a super-heavy class rocket with a LEO payload limit of 54.4T and GTO limit of 22.2T.

So, *at this point*, the Chinese have demonstrated a more powerful rocket than SpaceX has, yes. However, SpaceX demonstrated a heavy-class rocket before the Chinese did, and has a super-heavy design nearly ready to fly. To the extent they are ahead at all, it is fleeting.

Comment You got Russia and the US backwards. (Score 4, Interesting) 112

Um... where the hell did you get the idea that the Russians use gas generators (inefficient) and the US uses staged combustion? That is almost perfectly backward.

Staged combustion was invented by a Russian, Aleksei Mihailovich Isaev.
The first staged combustion rocket engine built was the Soviet S1.5400, first flown in 1960.
The (ill-fated) Soviet N1 moon rocket used staged-combustion NK-15 and NK-33 rocket engines (the American Saturn V moon rocket used gas generator rocket engines).
The first western (German, not US) staged combustion engine was in 1963, and it was a laboratory test only.
The Russian Proton rocket family was using the staged combustion RD-253 rocket engine in 1965.
The US buys staged combustion RD-180 engines from Russia for United Launch Alliance's workhorse Atlas rocket family.

As far as I can tell, the first US-built staged combustion rocket to fly was the RS-25, better known as the SSME (Space Shuttle Main Engine), which first flew in 1981. It was a fuel-rich staged combustion cycle, made possible by the use of non-coking H2 fuel. However, by that point the Russians had been using oxidizer-rich staged combustion (which requires advanced metallurgy that the US could not duplicate for over two decades.

Now, both SpaceX and Blue Origin are US companies working on staged combustion rockets, but those are recent projects. In SpaceX's case, it is a full-flow staged combustion rocket, which is extremely tricky; no FFSC rocket has ever flown, although the Russians built and test-fired the RD-270 in the late 60s. SpaceX's Raptor has successfully fired on a test stand, the first FFSC rocket engine to do so since 1970 and the only US-built one to do so ever. The US (through private contractors Rocketdyne and Aerojet) experimented with FFSC in the "Integrated Powerhead Demonstrator", which wasn't even a full rocket motor; the front-end ("Powerhead") component was tested at full capacity in 2006, but then canceled; no full rocket engine was ever built using that design.

So yeah, the US historically didn't have shit on the Russians when it came to advanced rocket combustion cycles. That may be changing now, but it's driven primarily by private industry.

Comment Re:The good folks at the Verge... (Score 1) 675

Needing to buy *another* external reader or an adapter (just to support USB-C, because all your existing card readers are USB-A) is insulting, though.

And, as another commenter pointed out, lots of DSLRs are now using SD instead. Nikon's highest-end DSLRs still use CF, but their entry-level and "enthusiast" models use SD. Sony uses SD (and their joke "Memory Stick (TM)" thing) on their highest-end ones. Canon's top-end EOS takes both CF and SD. So yeah, if you have a lot of existing CF and are still using it, then you'll be stuck with needing an adapter... but if you bought your camera any time in the last few years, odds are pretty good it supports SD, and newer storage cards are faster and higher-capacity, so there's a pretty good chance that you've replaced your media in the last couple years too.

Comment Re:Dear Apple.... (Score 1) 675

Also... the "card sticking out" thing is a really weird point of complaint. I mean, even my smallest USB flashdrive sticks out a few millimeters (it has to, or I wouldn't be able to remove it). Most stick out 3-5 cm (1-2 inches) when plugged in. Nobody seems to mind. You don't leave the SD card in the computer *permanently*, any more than you leave an external hard disk plugged in permanently.

Which, of course, comes to the even stupider part of that argument... it's not OK to have a SD card sticking out of a slot a cm or so (at most), but it's OK to have an external card reader sticking out of a USB port? Possibly by way of a USB-C to USB-A adapter, because nobody has USB-C card readers yet? That's going to stick out a hell of a lot further than any SD card ever would, and be a lot of hassle to make sure you don't lose or break.

Not to mention that it just looks... tacky. Not that this has ever stopped me personally, but it's a weird thing for an Apple spokesperson to advocate for!

Comment Re:Fuck You, that's why. (Score 1) 675

That might make sense... except USB-C is pretty much universally USB3, and it's got USB-C ports, so I'm pretty sure it already has a USB3 interface internally. They could easily have attached a UHS-II SD reader to one of those USB3 interfaces. Indeed, no need to have any dedicated USB2 support internally anymore, so I'd be a little surprised if they do.

Comment Posted from a Thinkpad (Score 1, Troll) 535

Specifically, from a T460s running Windows 10 Enterprise x64. It has the same trackpad design as the Carbon X1 in that link.
Sorry for being so blunt, but if you're going to confidently and publicly state such utter falsehoods, you'll take some flak for it.

  1. Is it multitouch?
    Yes (duh). All Windows laptop trackpads I've seen made in the last six years, and many before that, have been multitouch. I've got a laptop from 2006 with a multitouch trackpad. The $270 netbook-thing my mom uses has a multitouch trackpad.
  2. Can I scroll any window using a two finger gesture even if that window doesn't currently have focus?
    Yep. Built-in option in Win10. Settings->Mouse->"Scroll inactive windows when I hover over them". Some mouse / trackpad OEM drivers (including the ones used in my old Lenovo) supported it on older versions too.
  3. Can I drag with three fingers?
    Not what I have mine configured for - three-fingers left/right switches apps, down/up is minimize/restore - but in theory, sure.
  4. Show the desktop with four?
    Yep, or switch virtual desktops using left/right.
  5. Right click with a (silent) two finger tap?
    Yes, of course; like multitouch, this is one of the basic gestures that has been supported for many years.

No. Of course not. Because even if that trackpad did support multi-touch properly, Windows itself doesn't, and neither does Linux, making the support pointless.

It's 2016. Linux people. Make something that's not a UI disaster area. And Windows people... maybe just give up.

Have you considered the possibility that you're running your mouth off without a single fucking clue what you're talking about? You're making a bloody fool out of yourself, much like the person who modded you up. I thought the Apple "reality distortion field" was supposed to have died with Jobs, but if that's what you think the reality is...

Comment Re:They tell you upfront it isn't going to be good (Score 1) 191

They made a pretty big deal out of Tasha's gender, both with a few anvilicious episodes where a female chief of security was explicitly made to be a big deal and slightly more subtly in a few scenes where she was treated a little differently than the other officers or even just stood out as a woman among a group of mostly men (especially in Security). Still, you have a valid point: before big, strong, dark-skinned, male Worf, there was Tasha Yar as Chief of Security.

Comment Re:SpaceX Dragon 2 should be ready (Score 1) 87

Oooh, more details on the solid oxygen crystals cause idea? I hadn't seen that one yet.

Also, I hadn't heard that SpaceX and NASA disagreed on the cause of the CRS-7 failure... more like SpaceX figured out early that the symptoms matched a failed helium tank strut but didn't believe it at first because none of the struts they tested failed similarly, so they went on reviewing and ended up testing most of their strut inventory before they found a few (just two?) that were also dangerously weak. At no part of this did I hear anything about SpaceX believing that the probable cause was anything else, just that the initially-predicted cause seemed unlikely.

Comment Actual links (Score 1) 132 - the web site of the company / research lab building these things. Kind of hype-y, of course, but has some good info. - the section of the site that gives an overview of how the Neumann thruster actually works, how efficient it can get, and so on. Includes links to blog posts about a number of the fuels they've tested, such as (which has an utterly ludicrous specific impulse).

Comment Big difference in these ion thrusters. (Score 1) 132

Neumann thrusters work very differently from existing ion thrusters, though. At a high enough level, the concept is the same - ionize some stuff, accelerate it using an electric field - but the details matter a ton. Or, indeed, several tons. The existing ion thrusters mostly use gases - xenon is popular - as reaction mass. That means your reaction mass is already conveniently in tiny individual particles (single atoms, since it's a noble gas) suitable for extreme acceleration, but it also means you need to have a bunch of tankage, valves, and so on... and once the xenon runs out, you're done. Xenon thrusters - especially the most efficient ones, which use grids that the particles fly through - have a limited lifetime, too; they wear out pretty fast if you use them with a lot of power.

Neumann thrusters use solid fuels, usually metals (though they also tested with pure carbon, and it worked reasonably well). There's no tankage, no moving parts such as valves (although the fuel rods may occasionally need replacement), and no risk of your fuel leaking off into space. What's more, in theory you can simply use metal that is *already in orbit* (such as discarded rocket upper stages, end-of-life satellites, or even outright junk if you can catch it safely) and that means you can easily "refuel" while in orbit. The performance you get varies depending on the reaction mass, with some metals producing absurdly high specific impulses (11000 seconds?!? That's far better than existing ion thrusters) and some producing more moderate efficiency but permitting quite high thrust (well, relative to other ion thrusters; it's still measured in m/s of delta-V per month) if you have the power (without eroding any part of the thruster except the fuel rod, unlike a conventional ion thruster running at such power levels).

Some of it, like the in-space "fueling", is more than a little difficult, but the basic idea seems sound. It's also a pretty new technology, and they've already come up with some improvements (such as a magnetized "nozzle" that gives better thrust, presumably meaning it improves electrical-power-to-thrust efficiency) so I'm sure the technology will mature still further as research on it continues.

Comment Re:And I was modded down... (Score 1) 182

It was already up to the payload owner, not to SpaceX, whether or not the static fire was performed with the payload mounted. The first few Falcon 9s were all tested without payload. However, customers started opting for the post-integration test; it saved time (no need to take the rocket down again, attach the payload, and roll it back out). For people on tight schedules, it was deemed worth the risk; SpaceX had not, and still has not, ever lost a Falcon 9 stage due to engine failure*. I wouldn't be at all surprised if SpaceX's customers do indeed go back to testing without their payloads attached, but it will be, and always has been, their choice. It's not a matter of costs, either, just of schedule.

* There was a single engine failure on CRS-1, but it was non-catastrophic; the rocket shut down that engine and continued to orbit, demonstrating its engine-out capability. CRS-7 failed in the upper stage during the boost phase; the second-stage engine was not ignited (since it was still attached to the first stage) and the first-stage engines continued firing right up until the rocket came apart. This recent failure came before *any* of the engines were ignited, and started in the second stage (which wasn't even going *to* ignite).

Comment Re:Tanker Last ? (Score 1) 202

It takes multiple tanker runs to fully fuel one of the spaceships. They aren't likely to build enough tankers to have them all waiting in orbit for the moment eh spaceship finally launches. If it was a single run (like the video shows), it'd make sense to send the tanker first (unless boil-off is a particularly bad problem), but it's not a single run. More like 4-5 runs per spaceship.

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