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User: FatLittleMonkey

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  1. Re:Uhm... on Using Fuel Depots Instead of Giant Rockets · · Score: 1

    OMS engines were just variants of the standard hydrazine rockets, similar to the ones used on any satellite. (Although much more complex for human-rating.) Hobby rockets. You can turn them on and off all day.

    The SSME's are big LH/LOx rockets. Massively complex systems, and shut down is brutal.

  2. Re:NASA has no choice on SLS on Using Fuel Depots Instead of Giant Rockets · · Score: 4, Informative

    Falcon Heavy simply does not have the payload capability for manned, deep space flight.

    You didn't read the report? Or the summary? Or the headline?

    Nothing intended to launch on the 130 ton SLS has more than 50 tons dryweight. So instead of launching it fuelled on a $1.5 billion launcher, you launch it dry on a $0.125 billion launcher, and launch the fuel on some other $0.125 million launchers. $1.5 billion worth of mission for less than half price. Bargain!

    Even assuming Falcon Heavy is ready on time, SpaceX is still in business in 2014

    What chance do you think the SLS has of every reaching its first mission? On time, on budget. After burning through its $60 billion development budget?

    and they haven't started multiplying their prices after they have gone public

    They are signing commercial contracts at a list price of $125 million per launch. (Less if you don't need the entire 50 tons.)

  3. Re:How do you get to fuel depots without a rocket? on Using Fuel Depots Instead of Giant Rockets · · Score: 4, Informative

    As others have said, you use smaller rockets to launch the mission payload "dry", and to launch the fuel separately. But to explain the cost savings, let me use an example:

    The SLS is projected to cost over $60 billion to develop and around $1.5 billion per launch. The biggest version is supposed to launch 130 tons, but the first version will only launch 70 tons. (And remember, $60 billion is only for the rocket, it doesn't include the cost of the actual mission hardware.)

    SpaceX's Falcon Heavy will probably cost less that $0.5 billion to develop, and is already taking commercial orders at something like $0.125 billion per launch. It is intended to launch over 50 tons.

    For the price one 130 ton SLS launch, you could pay the entire development costs for Falcon Heavy and still have enough to buy 8 launches of 50 tons, or 400 tons total. And once Falcon Heavy is developed, each subsequent $1.5 billion could buy 12 FH launches, or 600 tons.

    600 tons for the same price as 130 tons.

    So instead of spending $60 billion to develop SLS, it could be spent on actual missions. Isn't that a more intelligent way to run a space program?

  4. Re:Uhm... on Using Fuel Depots Instead of Giant Rockets · · Score: 2

    "Re-entry and landing
    The vehicle began re-entry by firing the Orbital maneuvering system engines, while flying upside down, backside first, in the opposite direction to orbital motion for approximately three minutes, which reduced the shuttle's velocity by about 200 mph (322 km/h). The resultant slowing of the Shuttle lowered its orbital perigee down into the upper atmosphere. This OMS firing was done roughly halfway around the globe from the landing site."

    From "Space Shuttle" on.

    Once shut down, about 12 minutes after launch, the SSME's are never fired again until they have been removed from the orbiter and fully serviced.

  5. What? on Using Fuel Depots Instead of Giant Rockets · · Score: 4, Informative

    Did you read the report? It was comparing the cost of SLS launched missions to the moon or an asteroid, with depot enabled versions of missions to the moon or an asteroid. They weren't trying to argue that every rocket in the world is refuellable, nor even most, they were saying that launching a LTO transfer stage empty, then fuelling it in orbit, is cheaper to develop and fly than building a Really Big Rocket.

    You can launch a 100 ton lunar transfer stage on SLS, say, with a 25 ton dry weight and 75 tons of fuel.

    Or, you can launch the 25 ton stage empty on a Falcon Heavy or a Delta IV Heavy, plus three fuel missions on similar rockets, and it will cost billions of dollars less. (Their scenario is more detailed, obviously.)

    SLS is an expensive and harmful way to do these missions. It actually makes us less likely to go beyond Earth orbit, and wastes two to three decades and many tens of billions of dollars doing so.

  6. Re:A bit thin-skinned... on High Court Rules In Favor of Top Gear Over Tesla Remarks · · Score: 1

    We should sue.

  7. Re:And they say romance is dead! on SMH Outs Copyright-Violation Hunters As Porn-Pushing Brothers · · Score: 1

    I know you were playing, but for consent not to be withdrawn it must be capable of being withdrawn. If our drugged or drunk young slut is incapable of withdrawing consent, she is incapable of giving it, legally. Same as a child. And any form of coercion in sex is illegal in porn in Australia, even simulated. "Refused classification", same status as child porn. So our friendly neighbourhood Porn Brothers went from trading hacked accounts (also probably illegal in Australia, unauthorised access and all that), to peddling porn that is illegal in the very country they live, to Defending the Law from Dread Pirates.

    Colour me unimpressed with the height of their moral ground.

  8. The Kock Brothers? on SMH Outs Copyright-Violation Hunters As Porn-Pushing Brothers · · Score: 1

    n/t

  9. Re:And they say romance is dead! on SMH Outs Copyright-Violation Hunters As Porn-Pushing Brothers · · Score: 2

    Actually in Australia, all simulated sexual violence in porn is illegal. Even simulated-sex non-porn depictions of rape, where it encourages or celebrates rape, is also illegal.

  10. Re:Why? on All-Electric DeLorean Car To Hit the Streets In 2013 · · Score: 1

    Electrons?

  11. Re:Office Use? on Apple's Siri As Revolutionary As the Mac? · · Score: 1

    At least Bruce Sterling can claim prior art before Apple patents that...

    Maneki Neko

  12. Re:Weird? on NATO Exercise Banned From Jamming GPS · · Score: 1

    They are presumably not testing how middies cope with no nav, they are testing how the equipment itself responds to local jamming. (And whether those middies can tell when their systems are in the jamming zone or not. Ie, how they cope with the cognitive dissonance of unreliable information.)

    There's a big difference between "Okay, turn your nav screens off. We're doing a manual nav exercise today!" and dealing with nav systems which might be in error and which respond to signal jamming in different and random ways.

  13. Re:How can this not be prior art? on Apple Tries To Patent 3rd Party In-App Purchasing · · Score: 1

    You'd think it'd be easier to teach patent examiners what "non-obvious" meant. But no.

  14. I applaud this initiative on Florida School District Begins Fingerprinting Students · · Score: 1

    I for one applaud the Government educating our children on the techniques and technologies required to circumvent finger-print scanners, I'm sure such skills will be much sought-after in the future.

    It's a good age to teach kids how to spoof biometrics. By the time these techniques are mandatory for the general public most people will be past that age where you easily grok new technology. By forcing every generation to learn it in school, you guarantee the skillset will be widely available when needed.

  15. Re:And in related news... on FBI Plans Nationwide Face-Recognition Trials In 2012 · · Score: 1

    So the same as now?

  16. Re:Backup backup backup. on Mars Rover Curiosity Sealed Up For Launch · · Score: 1

    Ah. Fair enough.

    (Although, at the risk of flogging a dead horse, I suspect it would have seemed less impressive had they only flown the first MER, Spirit. Jammed wheel, later bogged. It would have exceeded it's designed life, but having Opportunity elevates the mission from "Successful" to "Wildly exceeded our every expectation!" Likewise, imagine Voyager 1 without Voyager 2, no Uranus/Neptune encounters. Beagle lander burned in, no backup meant no mission. Phoenix lander, glitchy from the start, failed first winter, no backup. With MSL, if there was a second one, you'd be pretty much guaranteed that one of them will outlast expectations.)

  17. Re:Another Mars rover? on Mars Rover Curiosity Sealed Up For Launch · · Score: 1

    Many different options have been explored, including, but not limited, to:

    Don't forget the proposed boats. We've never done boats before.

  18. Backup backup backup. on Mars Rover Curiosity Sealed Up For Launch · · Score: 1

    Rover, singular.

    Which is annoying. One glitch on landing, a stuck wheel, bad comms, whatever, and the whole mission is a waste. This not only wastes the existing mission, but poisons the next mission.

    Always make a backup.

  19. Re:I Want to Believe! on Does Italian Demo Show Cold Fusion, or Snake Oil? · · Score: 1

    The Steam temperature is very different than the water temperature. I'm assuming that while the steam temp dropped from 130 C to 120 C, the water temp dropped from 400 C to 99 C. If you put the steam temp sensor far enough away from the production source, this seems about right. Even at 400 C, the water won't instantly boil away, and especially not if it is under pressure. I'm beginning to understand exactly how this parlor trick works.

    I've been following the Rossi story for nearly a year, and you nailed what critics have been pointing out since day one.

    They've also pointed out how easy it would be for Rossi to prove his device works-as-advertised. You shove the output into an insulated tub of water. You let any independent observer measure input water temp, input power, and the before and after temp of the output tub, using their own equipment. Roll some standard calorimetric maths, and you've got the ratio of input energy to output energy. (And given that Rossi was claiming a 6x multiplier at the beginning, the measurements can be really crude and still detect "over-unity".)

    You don't have to measure inside the magic box, you don't have to show the magic beans, you certainly don't have to do their nonsensical "self-sustaining mode". You just use the same method that companies routinely use in a hundred industries to test the efficiency of any (very much under-unity) heat-engine.

  20. Re:Finally, a meta-thread! on Help Shape the Future of Slashdot · · Score: 1

    Perhaps a class of user between account-holder and editor. "Trusted user" or "Friend of Slashdot". Manually chosen regulars who have a history of useful suggestions/corrections, who do independent research, etc. Combined with a more wiki-esque Firehose, so the... Trustees... can collate dupes, improve links (direct to the source article, rather than to-my-blog-post-about-the-actual-article), fix typos, generally improve summaries, etc etc. More than just tagging spam.

    (Apparently Taco and co didn't want to allow users to uprate submissions directly because they wanted a quirky mix on the front page, not just another Digg. My suggestion would allow the combination of crowd-sourcing the submissions in Firehose, but retain the "quirky" mix on the front page.)

    I would also suggest that the meta-mod system be incorporated into the regular article/comment system. So it works like regular mod points (except, obviously, you are rating the existing modding of a comment, not the comment itself.) Being part of the normal comment reading system, rather than a whole separate section, would increase participation in the meta-mod system.

  21. Re:Even 2-5 minutes would help on Could Electron Counts Detect Major Earthquakes? · · Score: 1

    Thanks for the link.

    Note that even in the Wiki article, it says the Red Cross no longer recommends doorways because they are not structural. And yet the OP still automatically used the old "desk/door-jamb" canard. (Indeed, some of the links in the article casually contrast the "discredited" ToL theory with the "proven safe" technique of sheltering in doorways.)

    For me, the point about the Triangle of Life theory is that the old duck'n'cover advice is based on even less testing and experience than ToL. It was pulled out of someone's ass and then spread around for 50 years as if it were fact. Organisations keep spreading it on the assumption that someone must have tested it originally, or there wouldn't be so many other organisations saying it. (I've also seen this happen in other areas, where discredited advice is continued even after the professionals knew it wasn't true, because they don't want to "confuse the public".)

    For example, the Red Cross dropping the doorway recommendation, think about how long it's been since doorways were universally built as structural elements. (It's not as if home construction techniques have radically changed in the last 20 years.)

    (Don't get me wrong, I think Doug Copp is probably a loon. But the "Drop, cover, and hold on" advice is not in any way evidence based, it is just a myth.)

  22. Re:Even 2-5 minutes would help on Could Electron Counts Detect Major Earthquakes? · · Score: 1

    The better idea is to implement tighter regulations to ensure building are designed to be more earthquake resistant in high risk zones and possibly providing very high strength safety zones that will form a protective zone in the event of a collapse.

    Errr, all that in 2-5 minutes?

  23. Re:Even 2-5 minutes would help on Could Electron Counts Detect Major Earthquakes? · · Score: 1

    Try to find something that has a relatively strong structure above you, such as a strong desk or a doorjamb. The idea is that if your house buckles and falls, it will help divert some of the energy away from you.

    This is a myth. The problem is that modern buildings and furniture aren't strong structures. If you crawl under you cheap laminated table, or flimsy wooden framed fibre-board clad doorway, you are just providing the roof with something to crush you.

    Supposedly the best method is to lay beside, not under, something with a low centre of gravity. Ie, between a table and a sofa. Between a desk and a low bookcase. The idea being that when those things are crushed down by falling ceiling beams, they can't flatten completely, so they create an airpocket beside them. Keeps you alive long enough for rescue.

  24. On the gripping hand on Wikimedia Foundation Enables HTTPS For All Projects · · Score: 1

    Now I have to remember my damn wikipedia password.

  25. Re:Another Big Announcement on SpaceX Reveals Plans For Full Launch System Re-usability · · Score: 1

    It's not hard to give "more bang for their buck" when you're not concerned with making a profit.

    SpaceX has been profitable for the past few years. It has $3 Billion of orders on the books. (For example, they have the contract for the Iridium constellation upgrade.)

    To say that SpaceX did something "for less than NASA spent on the Ares I/Orion launch system" is not really meaningful when you're doing something without profit.

    "Did something"? For the price NASA paid for one single component of their capsule, SpaceX built a whole capsule, and the whole launcher, and "tested" them by actually putting it into orbit and recovering it.

    (Oh, and it was "Launch Abort System". Not "launch system". The launch abort system is that little tower on top of the capsule, with small rockets that pull the capsule away from an aborted launch. $600 Million spent so far for just that.)

    When SpaceX starts spending the kind of lobbying dollars that those guys spent to get contracts and that all gets baked into the bottom line along with profits it's not going to be such a huge savings.

    And that's a criticism of SpaceX? Seriously? Are you out of your fucking mind?

    or at least do something that wasn't done half a century ago.

    Let me repeat: NASA today cannot do any of those things any more. Nor can any of NASA's traditional contractors. They have less capability today than they had in 1960. NASA cannot put men into orbit. NASA can't even deliver cargo to the ISS. And the money they have already spent failing to develop a single new launcher and capsule is over an order of magnitude higher than SpaceX has spent in its entire existence.

    The price that NASA will pay trying to develop SLS could pay for the development of SpaceX's Falcon Heavy and the man-rating of Falcon9+Dragon and buy over ONE HUNDRED LAUNCHES OF EACH. Ie, 5000 tons to orbit, and 700 astronauts. Why don't you think about that for a moment.

    SpaceX is putting out press releases about an unmanned craft in orbit

    No, SpaceX PUT a capsule in orbit. They didn't just talk about it. They are the first commercial launch company in history to launch and recover a space-capsule.

    NASA recently put out a press release (and video) of a single test firing of the J-2X engine. SpaceX (in an FAA application) stated that it averages FIVE tests of Merlin engines PER WEEK, and a test of a full nine engine F9 first stage every two months.

    Oh, and NASA will pay $1.2 Billion to develop that J-2X engine (the upper stage engine for the SLS.) That's over four times what SpaceX spent building and launching the ENTIRE Falcon 9. Just for a single upper stage engine, not even for the whole upper stage.

    I'm not sure why a segment of the tech nerd community has decided to be wowed by SpaceX. I don't know if they really believe that this is going to herald in some new age of being able to hop on a space elevator for the cost of a Chicago-Minneapolis flight and visit Alpha Centauri or something. If any other technology company was making as much hoopla about so little as SpaceX, they'd be laughed off Slashdot's Idle page.

    US commercial launch operators have lost the commercial satellite launch market. The only satellites they launch today are for DoD and NASA. All the commercial satellite market has gone to Europe and Russia, with India and China catching up. Worse, the primary US government launcher, Atlas, relies entirely on imported Russian rocket engines. And the US operators had no ambition to try to win that market back (nor to lessen their dependence on Russian engines.)

    Until SpaceX.

    SpaceX's existing two launchers are already the cheapest in the world. And it's third launcher will be the largest in the world.

    Cheapest in the world. Largest in the world. Already profitable. Massively ambitious. Why does that so offend you?