* Posts by cray74

970 posts • joined 29 Nov 2011

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Falcon 9 gets its feet wet as SpaceX notch up two more launch successes

cray74
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Re: NASA has concerns over SpaceX culture??!?

but they've sat on their ass and not done any significant basic rocket research since the '70s WHICH IS THEIR JOB

What do you define as "significant basic rocket research?"

NASA has been steadily testing rocket engines, propellants, and structures since the 1970s. Aerospikes, composites, exotic propellants, new engine cycles - they all get tested at NASA. And it hasn't ignored the atmospheric side, either. Whether it's looking into quiet supersonic transport or more efficient jet engines, aircraft and engine makers benefit strongly from NASA's ongoing research.

But then there's that valley of death in implementation. A new rocket is billions of dollars of investment, so how is NASA supposed to apply some great innovation if the commercial world doesn't want to spend $5 billion on a new model rocket and the White House or Capital Hill deletes the moon/Mars/space base program that needed the rocket?

They've talked about recovering boosters FOREVER and not done it.

NASA recovered very large boosters over 130 times. I work with some of the team members that cleaned up and prepped those recovered boosters for the next launch. If you want NASA to build additional recoverable boosters of some new form, then I'd suggest:

1) Get Congress to secure several billion in funding

2) Get a commercial partner to build the boosters, because NASA never had a significant rocket factory

3) Get Congress to not cancel the years-long contract after the next election

All NASA can do in such an organization is lobby, plead, and argue for money. It doesn't set the federal budget that decides how it can innovate.

And Gemini was supposed to be recovered by parasail, and they bottled out again.

The short version is that Gemini's Rogallo wing development was slower than the rest of the program. They had a spaceship ready to fly while the Rogallo wing was still failing. Rather than let that hold up the program, NASA "got'er done" with plan B: parachutes.

The longer version is that while the Gemini capsule developed rapidly the Rogallo test vehicle ("Parasev") handled poorly in the air, crashed, and had a steep learning curve. (Gemini wasn't using proven commercial Rogallo hang glider technology. Instead, it was developing the technology that would lead to Rogallo wings in hang gliding use.) And just as the Parasev started working well, the Rogallo wing-equipped Gemini capsules were running into problems. Wind tunnel tests showed the capsules' wing liked to disintegrate in adverse landing conditions. (Solution: only land in nice weather.) Beyond the wind tunnel tests, there were problems with deploying the wing in real world conditions, which led to destruction of test vehicles.

Instead of spending another couple of years ironing out the Rogallo wing, NASA launched the Gemini capsule with parachutes and the USAF looked into "Winged Gemini." It was a get'er done attitude that didn't let technological setbacks or paperwork hold up the program. Speaking of which...

Commercial crew is ready to go, except NASA can't get the paperwork together.

NASA has the blood of 17 astronauts on its hands from other times when it decided to ignore the paperwork and just go ahead with the test or launch. Apollo 1: rushed too fast, numerous deficiencies in blueprints, testing and safety, three dead astronauts. Challenger: ignored the flight data that said the SRBs had a leakage problem and ignored the spaceship's manufacturer's paperwork that said, "Shuttles are not meant to launch in this weather," seven dead astronauts. Columbia: smoothed over safety briefings identifying risks in heat shield damage, seven dead astronauts.

Now, NASA is responsible for vetting US-built spacecraft as safe for human flight. It probably is going to go a bit slowly.

cray74
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Re: Bowl of Rice?

Seriously, have you looked at that URL you pasted?

Apparently not the way you meant. The chain was:

Google Image Search: Bowl of Rice SpaceX

Look for the amusing pic found on Facebook of a Falcon 9 in rice: no luck

Look for another pic of tech in rice: found many

Look for page not flagged by security: found some

Look for short-ish link that isn't 7 lines of text long: found several

Paste in to Register post with bits of code

Test link when Previewing message: opens without problem, pop-ups, or security warnings

Submit

cray74
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Headmaster

Gruesome Post-Mortem

While SpaceX is interested in the failed hydraulic pump on the grid fin, I would love to see what happened to the single engine that was running when the Falcon 9 stage dropped into the water. The thermal shock, hot corrosion, unplanned back pressure - that'd make for an interesting materials failure analysis.

Naked women cleaning biz smashes patriarchy by introducing naked bloke gardening service

cray74
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Re: Doesn't everything green have thorns in Australia?

What kind of gardening are they doing, trimming some bushes and plucking some fruits?

My brother runs a lawn care service on the side in Florida. It is a dirty, sweaty job that is the antithesis of sexy. Just normal mowing, even with a catcher bag, produces a cloud of dust and grass duff that gets everywhere. The cloud of lawn shrapnel gets more exciting when the yard's owner has a dog, which tend to leave fragrant landmines for the mower to trigger.

And sweat - it was cost effective for him to buy a hotel-scale ice maker to fill his ice chest rather than collecting drinks and 10 pounds of ice from a store every morning.

FYI: NASA has sent a snatch-and-grab spacecraft to an asteroid to seize some rock and send it back to Earth

cray74
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Re: Serious Question

Care to explain how much gravity that 500m diameter accretion of dust and mystery is generating,

10 micro-Gs according to Wikipedia's physical characteristics panel on Bennu. It also has density and mass values.

and how much effect that will be having at 7 kilometers distance ?

Not much. Wellyboot already provided the reference showing Osiris is in orbit around Bennu, but there are times where the various asteroid and comet chasing probes aren't so much "orbiting the object" as "strolling around the sun beside it." Hayabusa hovered beside Itokawa for a while, and Rosetta hovered off 67P/Churyumov–Gerasimenko before some of its orbital operations.

cray74
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It won't contain any clays unless I'm more out of touch with notions on how bodies form from a stellar accretion disk than I realised.

Asteroidal clay has been proposed for radiation shielding. Unfortunately, my lackadaisical search didn't find any substantial papers on clay and asteroids, just discussions that assumed the clay existed.

cray74
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there is less than a 1 per cent chance of that happening, based on current data

So you're telling me there's a chance!

NASA's Mars probe InSight really has Mars in sight: It beams back first pic after touchdown

cray74
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Trollface

Re: I Am Spartacus

3. the image was *embedded* *in* *the* *story*.

So, wait...where can I find these images you're talking about?

cray74
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Re: Well done

They keep a lens cap on to protect the under-deck camera from the dust that blown up during landing.

The rockets are no joke. Despite all the efforts to protect Curiosity, including using the "sky crane" design, Curiosity's wind sensors were damaged by flying debris during landing.

What the #!/%* is that rogue Raspberry Pi doing plugged into my company's server room, sysadmin despairs

cray74
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Re: easy pickings

My email (username) and password still worked.

Wow. At the other end of things, when a downsizing caught me my access was cut-off mid-email the morning I was booted out the door. While I was getting the bad news from HR (over the phone, because the local HR rep had been laid off before me), I had been trying to email coworkers to pick up my remaining tasks and notify customers. But IT had deadlines to cut access and happened in the middle of the call.

Since the company had been shriveling for some time they had apparently dealt with a number of emails from terminated employees that contained less-than-professional departing comments, hence the hurry to cut access.

Subsequent emails from the company, such as for termination benefits, went to my personal email address.

Big Falcon Namechange for Musk's rocket: BFR becomes Starship

cray74
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Re: You'd have to be a Dummy,....

DC-X was demonstrating vertical rocket landing in 1980s

The DC-X first flew, for 59 seconds, on 18 August 1993.

and still need be completely disassembled and rebuilt after landing.

The DC-X, Falcon 9, and New Shepherd all reuse(d) engines without significant rebuilds between flights.

cray74
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Re: You'd have to be a Dummy,....

SpaceX - we took nine exactly same rocket booster NASA designed in 1960 for Lunar module

Saying the Merlin is exactly identical to a LEM engine is like confusing the 5.2 L Aston Martin AE31 twin-turbocharged V12 for a VW Bug's 1100cc H4 because they both use pistons. Yes, it's true, they're both piston engines. They're not exactly the same, not even the piston design.

Specific to the rockets, a few points:

1) The Apollo LEM's descent propulsion system was developed by the private company Space Technologies Laboratories (TRW), not NASA.

2) The SpaceX Merlin engines shared the same style of propellant injector, a pintle injector, as the LEM's descent propulsion system, but SpaceX's injectors differ in alloy, size, shape, and design.

3) Merlin engines use different propellants than the LEM's descent propulsion system

4) Merlin engines have vastly more thrust than the LEM's descent propulsion system

5) Merlin engines use turbopumps to deliver propellants, which differs from the pressure-fed LEM descent propulsion system

6) Merlin 1C and later engines are regenerative cooling, which differs from the ablatively-cooled LEM descent propulsion system

7) Merlin engines use a different combustion chamber design than the LEM's descent propulsion system

8) Merlin engines use a different nozzle design than the LEM's descent propulsion system

9) Merlin engines use different alloys than the LEM's descent propulsion system

The Merlin engine shares a single general detail with the LEM's engine, which is a pintle-type injector. It differs in all other major aspects of rocket engine construction: thrust, propellants, pumping method, cool design, and construction techniques.

Holy moley! The amp, kelvin and kilogram will never be the same again

cray74
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Re: Sad case of science ignoring the evidence

Except both platinum and iridium are more expensive than gold.

Now, yes. However, platinum used to be considerably cheaper than gold.

cray74
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Re: @A.P. Veening Economists - In 1889?

But the ideal keel material would be osmium.

Osmium oxidizes too easily and its common tetroxide is poisonous. It also only offers a slight density gain over platinum, which is more common and better behaved chemically, and only a modest gain over tungsten and uranium.

Another approach to enhance sailboat performance is switch to a multi-hull so you're not burdened with a heavy keel.

cray74
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Re: @A.P. Veening Economists - In 1889?

If I was a billionaire, I think I'd have a boat with the heat exchangers made out of platinum iridium alloy, because I could. No corrosion worries.

If the rest of the boat is made of non-platinum group metals then you'd need to be careful of galvanic (dissimilar metal) corrosion. Platinum's at the far end of the galvanic series so it's a threat to most other metals. It's relatively easy to address if you can separate the metals with non-conductive barriers (e.g., paint), but I wouldn't say "no worries."

Douglas Adams was right, ish... Super-Earth world clocked orbiting 'nearby' Barnard's Star

cray74
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Re: As for ion drive, where do you propose to get the energy from?

If you can use a planet's gravity to slingshot (i.e. accelerate) a probe, why couldn't you use one to slow it down too?

Periapsis burns are standard practice for capture. Cassini and Galileo both depended on planetary gravity to help their captures.

Rocket Labs mean business, Brits stick pin in Mars map, and Japan celebrates HTV-7’s dive into the atmosphere

cray74
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Re: Hippy-friendly hybrid-electric rocket motors

and as each one is depleted it is jettisoned

Cool, I didn't know that.

cray74
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Hippy-friendly hybrid-electric rocket motors

I'm still boggling at the use of electric turbopumps on the Rocket Lab's Electron, but if you only need 1 megawatt (those 9 engines are tiny) for about 2 minutes then that's about 33kWh and not too bad.

The engineering and development advantages are interesting. You entirely eliminate all the turbomachinery of the fuel pumps, so that makes development easier. You're not diverting propellant to run turbines, so the engine can gain efficiency without the plumbing complications of a staged combustion engine.

The drawback is a heavy battery pack, but it'll be lighter than an electric car's because you don't care about reusability and good recharging characteristics.

I wonder how electric pumps would scale to larger rockets that use turbopumps in the tens of megawatts.

I found a security hole in Steam that gave me every game's license keys and all I got was this... oh nice: $20,000

cray74
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Re: Tsk tsk tsk

Elimination of intellectual property law equals life upgrade for the entire world

Or quick development of coercive monopolies. If you take regulations out of the picture, then historically the groups that tend to profit the most are those who have lots of money and legal clout to make their own rules.

In news that will shock absolutely no one, America's cellphone networks throttle vids, strangle rival Skype

cray74
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A couple of Net Neutrality questions from a non-IT sort:

1) Is throttling or blocking allowed for an infected device spewing malware under the US's Net Neutrality rules?

2) What is the UK equivalent of the US's Net Neutrality regulations?

FYI NASA just lobbed its Parker probe around the Sun in closest flyby yet: A nerve-racking 15M miles from the surface

cray74
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Paris Hilton

Re: Glad they got there OK

I was worried they were going the wrong way when they launched it at night.

If they had really sent Parker to the sun at night then couldn't they have done away with all that heavy heat shield mass?

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.

.

I will forever regret not using that question at a Q&A with a representative of the ESA's Solar Orbiter team.

cray74
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Re: So what I'm wondering now...

But is velocity still a Constant in these circumstances?

No. As you noted, the probe accelerates (changing speed and heading of the velocity vector). From this plot of Parker's course, you can see how the time intervals change with position. It takes longer to cover the same distance when further from the sun - Parker slows down. Another plot also shows distance (in solar radii) and time, with zoomed in section of the closest approach.

And as noted in the font of all human knowledge, Parker is barely puttering along at Venus (26km/s) but accelerates to 120km/s near the sun.

So, in short: Parker moves much faster at periapsis (the close point to the sun) than at apoapsis (furthest point).

Astroboffins spot one of the oldest, coolest stars in the universe lurking in the Milky Way

cray74
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Re: Hydrogen is a *good* coolant

because its low density, high specific heat, and high thermal conductivity make it a good coolant.

I was going to say the same thing. I wonder what makes hydrogen a poor coolant in space.

Dawn of the dead: NASA space probe runs out of gas in asteroid belt after 6.4 billion-mile trip

cray74
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Re: Dear NASA

Satellites could use a backup Electro-Magnetic drive to putter back to Earth orbit.

Nope, since the electromagnetic drive has been debunked.

cray74
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Re: This seems like a good argument for ion drives

What I'm curious about is whether it also has reaction wheels or similar for attitude control, whether those had also failed.

Yes, and yes.

The third of four reaction wheels failed in 2017. Dawn has had reaction wheel failures throughout its mission. At Vesta, wheel failures led to "hybrid" thruster/wheel operations, and the approach to Ceres was an odd overshoot-and-return because Dawn couldn't perform a typical spiraling ion engine capture orbit with (then) two functional reaction wheels.

Core-blimey! Riddle of Earth's mysterious center finally 'solved' by smarty seismologists

cray74
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Re: out of curiosity

carbon steel is a completely different beast to iron and only has 2% carbon in it

Nitpick: the vast and varied family of alloys known as "carbon steel" covers steels with 0.05 to 2.1% carbon. With more carbon they're called "cast iron" and below that they're just iron...or steel. Some steels (especially some of the stainless family) hate carbon and try to exclude it.

More on topic: While the many other elements in the core are worth considering, it is hard to do so. Even for a fixed alloy composition, mechanical properties, magnetic properties, and even chemical properties will vary by temperature, pressure, and time, hence the T-T-T (Time-Temperature-Transformation) diagrams used in metallurgy for plotting heat treatments. You can get substantially different properties for an alloy held at high temperatures because of different crystal structures, different amounts of segregation of alloying elements, and other microstructural changes.

The problem with estimating the impact of other elements on the core's properties is that a) the exact composition is unknown and variations smaller than 0.1% can be significant; b) the core sits at a combination of temperature and pressure way off the usual metallurgy charts; c) it's hard to even simulate the core's conditions for more than a fraction of a second in diamond anvils or nuclear explosions, which makes normal metallurgical tests** challenging; and d) there are probably regional variations in composition just like the crust and mantle, and there are certainly temperature and pressure variations across the core's radius.

So it'd be hard to fault geologists for approximating the core as a big lump of nickel-iron. They do, on occasion, allow for the presence of uranium and potassium-40 to help estimate the radioactive heat budget of the core.

**My lab's Instron tensile test rig has a small environmental chamber fit for -100C to +600C at one bar of pressure (air or clean, dry nitrogen). There might be error if its results were extrapolated to the core's conditions.

Leaked memo: No internet until you clean your bathroom, Ecuador told Julian Assange

cray74
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The US has the highest incarceration rate of any country in the world yet also the highest crime rate in the OECD

Crime RATES or total number of crimes? The US undoubtedly has higher murder rates (absolute and per capita) with only the OECD's Turkey giving it a challenge on a per capita basis, but its rates of property crime (burglary, mugging, theft) and assault are less exceptional on a per capita basis. The UK, for example, has higher burglary and robbery per capita than the US.

JAXA probe's lucky MASCOT plonks down on space rock Ryugu without a hitch

cray74
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Re: Raumfahrt?

Yeah, I know, it's amazingly hilarious when words in a foreign language sound a little bit like the sort of thing which makes five year old children laugh hysterically.

Jokes like that are the reason for the standing proposal before the International Astronomical Union to rename the seventh planet to Urrectum.

US and UK Amazon workers get a wage hike – maybe they'll go to the movies, by themselves

cray74
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How to pay for $15/hour?

According to a cousin who works at Amazon - so this is a sample-of-one anecdote - Amazon took out a restricted stock reward to pay for the raise, but most Amazon associates don't hit 2 years for them to get the stock reward anyway.

So, can anyone confirm that Amazon was cutting stock rewards to pay for higher wages?

Brit startup plans fusion-powered missions to the stars

cray74
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Re: There wouldn't be any fallout

They have a lot of power, but even if you could direct all the charge at the back of the spacecraft, what the hell are you going to build the back out of for the nuke to push against that won't be destroyed in the process? If you used something designed to ablate somewhat with each charge, then your starting mass will be much larger and first nukes less efficient.

Dyson's concept, evaluated with plasma pulses against assorted targets, was that a plain steel pusher plate for a 6,000-ton surface launched vehicle would experience less than a millimeter of erosion. Larger, higher velocity interstellar Orion vehicles assumed the use of some sort of grease or water as an ablator, or used VERY large copper pusher plates that could handle the heat load and cool between pulses.

And note the nukes aren't bare nukes. They also include a substantial reaction mass to capture more of the nuke's energy and, at the same time, reduce the temperature of the pusher plate. Dyson planned on using disks of tungsten for a propellant.

cray74
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Re: Interstellar fuel

Would be a good idea to get ion thrusters to use methane as a fuel... Capture the farts of the spacefarers, and use it for propulsion!

A number of propulsion systems utilizing wastes from the ISS's life support have been seriously considered. It isn't unusual for waste systems optimized to recover oxygen (from CO2 or water) to end up with waste methane, hydrogen, and/or carbon that could be adopted to ion- or arcjet propulsion.

Why are sat-nav walking directions always so hopeless?

cray74
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Re: Hahaha...

I did walk down to the local mall a few times whilst staying there and got stopped twice by the police to ask what I was doing.

It's interesting how US history - short as it is - shapes things like walking. Manhattan is an emphatically pedestrian city with something approaching adequate mass transit. As a student, I had no trouble walking around the core of Atlanta, getting from campus to interesting malls or DragonCon on foot.

On the other hand, cities that grew up after the arrival of the car are car-obsessed, like the suburbs of Californian metropolises. Orlando is particularly nasty because it set a lot of its core roads in the 1950s-1960s when air conditioning made Florida real estate attractive and Detroit told the US no one would walk anymore. But then its population exploded from about 100,000 to 2.3 million in 50 years thanks to the Mouse's arrival. The car-oriented road system is unfriendly to pedestrians to begin with but has had trouble growing to accommodate the population. Orlando has something like twice the national average rate of turning pedestrians and bicyclists into road pizza.

NASA to celebrate 55th anniversary of first Moon landing by, er, deciding how to land humans on the Moon again

cray74
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Re: De-orbit ISS

Until it becomes cheap enough to lift lead shielding or they come up with some sort of equivalent to a sci-fi ship shield

Lead? If you want to block all radiation including cosmic rays, you need about 10 metric tons of any mass per square meter of hull. If you want it to be thin, then you use 10 tons / square meter of lead. If you want to be strong, then you use 10 tons / square meter of steel. If you want it to be broadly useful for astronauts, then you use 10 tons / square meter of water, food, and feces (hopefully in separate storage systems).

Though 1 ton per square meter is plenty if you're not planning to spend a life time on the station.

If you want to avoid lifting a lot of stuff out of Earth's gravity well, then use lunar or asteroid material: water or regolith. Parking a space station in lunar orbit is a good motivation to start some in situ resource utilization by mining the moon for water, metals, oxygen, and whatever else captures your fancy.

cray74
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Re: De-orbit ISS

Only if you want to do it the inefficient way. The smart way is to use a few ion engines, letting them slowly enlarge the orbit until a lunar capture is effected, then tightening that orbit.

If you don't mind the ISS spending a few months climbing through the Van Allen Belts, then that's fine. You're not going to be able to change its orbital plane until it has climbed above the belts, either.

cray74
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Re: De-orbit ISS

Is it really not possible to put it into orbit around the Moon? or Mars?

It's possible, just challenging. To get out of Low Earth orbit and into Low Lunar Orbit would require about 4500m/s of delta-V (with margin). An efficient hydrogen-oxygen rocket strapped to the 500-ton ISS would need about 900 tons of fuel. Since the biggest proven rockets can deliver about 100 tons to the ISS, that's a lot of Saturn V-equivalent launches to move the ISS.

Some credential-stuffing botnets don't care about being noticed any more

cray74
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Re: Maybe just

At best the new password will just 1 have added to the number part.

I can tell one of my engineering managers has been employed here since passwords were 6 characters shorter. I usually sit in the morning conference room where I can see her log in, and there's a distinctive bit of typing where she adds 6 repeating characters at the end. I've been tempted to send her a Register article on password security but that might not be as amusing to her as it would be (briefly) to me.

Her predecessor, on the other hand, had an incredible password that was way longer than required and had her two-hand typing all over the keyboard. When asked, she said she used phrases from favorite novels. I've always wanted to do that but I have trouble remembering where I put the numbers and non-alphanumeric symbols.

Apple hands €14.3bn in back taxes to reluctant Ireland

cray74
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Dear Sir,

I have been requested by the Irish Corporate Tax Escrow Fund to contact you for assistance in resolving a matter. The Irish Corporate Tax Escrow Fund has recently collected a large sum of taxes from the Apple Corporation. The taxes have immediately produced moneys equaling € 14,300,000,000. The Irish Corporate Tax Escrow Fund is desirous of releasing this money to taxpayers, however, because of certain regulations of the Irish Government, it is unable to move these funds.

You assistance is requested as a non-Irish citizen to assist the Irish Corporate Tax Escrow Fund, and also the Central Bank of Ireland, in releasing these funds to taxpayers. If the funds can be transferred to your name, in your United Kingdom account, then you can forward the funds as directed by the Irish Corporate Tax Escrow Fund. In exchange for your accommodating services, the Irish Corporate Tax Escrow Fund would agree to allow you to retain 1%, or € 143,000,000 of this amount.

However, to be a legitimate transferee of these moneys according to Irish law, you must presently be a depositor of at least €143 in a Irish bank which is regulated by the Central Bank of Ireland.

If it will be possible for you to assist us, we would be most grateful. We suggest that you meet with us in person in Dublin, and that during your visit I introduce you to the representatives of the Irish Corporate Tax Escrow Fund, as well as with certain officials of the Central Bank of Ireland.

Please call me at your earliest convenience at 1890 201 1060. Time is of the essence in this matter; very quickly the Irish Government will realize that the Central Bank is maintaining this amount on deposit, and attempt to levy certain depository taxes on it.

Yours truly,

Prince Garret FitzGerald

New MeX-Files: The curious case of an evacuated US solar lab, the FBI – and bananas conspiracy theories

cray74
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I always WONDERED why they used Mercury bearings

Maybe because the tiny group of engineers and specialists who build astronomical instruments are familiar with mercury, not the alternatives.

My division of an aerospace company loves metals, and it likes generous mid-range alloys like 6061 aluminum and precipitation hardened stainless steels (17-4, 15-5, etc.) When we recently needed a stronger, more fatigue-resistant aluminum alloy that led us to pick from the 7000 series, we had to learn partly by trial and error how to deal with its its forging, heat treating, and repair/rework behavior. It's been an expensive learning process figuring out an aerospace industry workhorse alloy because no one on the project has worked with it before.

If it hadn't been for a customer both willing to fund our learning curve and remain unyielding on over-the-top safety margins, we'd be back to 6061 in a heart beat.

So I can completely imagine some instrument maker faced with the tight budget of a grant-funded astronomy lab sticking to old, tried-and-true mercury solutions rather than trying to research and master replacement materials.

Russia: The hole in the ISS Soyuz lifeboat – was it the crew wot dunnit?

cray74
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They used to use velcro ... until Apollo 1

They still use Velcro in space. The role of Velcro in ISS sandwich making

2-bit punks' weak 40-bit crypto didn't help Tesla keyless fobs one bit

cray74
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Re: Problem-solution dichotomy

It gets me that the VERY NEXT ACTION you take is to touch the door.

That's what I do, and all I have to do: touch the door with the keys in my pocket. When I'm juggling groceries or kids I only have to hook a finger under one of the front door handles. The key fob talks to the car remotely and the door unlocks.

Other remote functions are handy. When my hands are a bit more free and I'm more distant from the car - like at the edge of my employer's baking, low latitude parking lot - I can remote start the car and get the air conditioning working while I cross hectares of simmering asphalt.

Pluto is more alive than Mars, huff physicists who are still not over dwarf planet's demotion

cray74
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Re: Not University of Florida

University of Central Florida - much smarter boffins!

UCF's professors of astronomy might be smarter. My experience with the engineering interns of UCF and UF is that University of Florida students need less remedial training and hand holding to get started in the work place. UCF just seems to leave out little details in lab work, team work, and technical communications that UF addresses.

Neutron star crash in a galaxy far, far... far away spews 'faster than light' radio signal jets at Earth

cray74
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Re: And that's why I don't bother with these comments sections any more.

So I have concerns about the research or about how it was reported.

It usually helps to provide a link if there's a factual error in the article. If your objection is to how the article's reported then it's more constructive to use the link in every Register article ("tips and corrections") that lets you inform the writer because they don't always check the comments section.

But, to give you a response on your concerns:

That collision, I thought, resulted in a bigger neutron star and not a black hole, according to the observation I seem to recall.

Current speculation is that a black hole resulted, though there are disputes because it'd be the lightest black hole yet found.

And even if it did somehow turn into a black hole after some time, how can that effect the gravity field of the new object at a distance?

I don't follow the question because the new object IS the black hole. The gravity field effects happened prior to the collision in that the two spiraling neutron stars shed orbital energy by radiating gravity waves. This loss of energy eventually caused the neutron stars to collide, spew gold everywhere, and collapse into a black hole or larger neutron star.

Afterwards, all the exciting effects are from conventional gamma ray and radio wave emissions from the resulting accretion disk, which is the topic of this article.

I believe at best these are separate events that just happened in the same area of the sky at similar times from our point of observation.

Three events that behaved as if they're related? Observations show neutron stars radiating gravity waves spotted by LIGO, followed the gamma ray burst consistent with neutron stars colliding, followed by radio emissions of an accretion disk from the debris cloud - that's rather consistent with a single event, not several related observations happening in the same space.

Roskosmos admits that Soyuz 'meteorite' hole had more earthly origins

cray74
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Re: Makes me wonder

What would happen if a similar hole was drilled in the Bigelow module

The Bigelow modules, like Transhab before them, are 50cm of layered ceramic cloth, foam, and fiber-reinforced pressure films. The hole wouldn't grow because of the rip-stop nature of the armor and strength layers.

Repair would be interesting. You'd be filling a 50cm-long bore and trying to get an adhesive to stick to polymers that sometimes don't play well together. However, given the small diameter of the hole and low stress (a few pounds of air pressure at the most), a long plug of epoxy injected in there would probably stick and hold in place.

cray74
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Did it occur on the ground or in space?

The picture seems to include some drill marks in the surrounding paint, which implies it happened after assembly of the Soyuz's orbital module.

The whole "drilled and filled with adhesive" sounds a lot like some of the repairs I've specified for bad castings** used in aerospace applications, so I could believe it happened on the ground. Then again, that sort of repair usually happens long before painting. If the repair is decided after painting, we strip the paint, patch the hole (Loctite ea9394 is awesome), sand down to tolerance, and repaint. You wouldn't have those drill skip marks around the hole.

**The stainless steel castings are expected to hold some pressure because the sensors and electronics behind them are air-cooled, but a) there are no lives depending on the pressure seal, and b) the strength margin is ludicrous, so some high strength epoxy in a casting porosity is safe. One of them came back to the factory missing one of its sapphire window panels, paint half blistered off, and packed with mud and fire retardant - it turned out to have been under the wing of a British Harrier that had a bad landing in Afghanistan. We were able to use the casting to train factory operators in window installation because it was still within its dimensional tolerances of +/- tiny.

Trainer regrets giving straight answer to staffer's odd question

cray74
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Re: Still happens

it is AMAZING how butter-fingered the sales people become, and how many times their laptops "slip out of their hands whilst running on a pavement".

Instead of breaking unwanted hardware, have you ever encountered bribery for new equipment and did it work?

I've found that polling the IT department for favored cookies and sodas, and leaving unsecured packs of the preferred snacks at my desk helps the quality of hardware I receive during a refresh.

Space station springs a leak while astronauts are asleep (but don't panic)

cray74
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Re: How did they find it?

Step 1: seal each compartment, monitor each compartment for pressure. This identifies the compartment the leak is in.

That was the basic technique . A 2mm hole wouldn't generate a draft that would stir dust or light objects.

I'm surprised El Reg didn't mention that prior to taping the puncture, an astronaut (Alexander Gerst) plugged it with his finger.

Drama as boffins claim to reach the Holy Grail of superconductivity

cray74
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Re: Context, context, context

When I complained to my physicist friend about twenty five years ago, he responded, "liquid nitrogen is cheaper than milk."

Cheaper than milk, soda, and unleaded. In the 1990s, the lab I worked at was purchasing liquid nitrogen at about $0.06 per liter. It led to some interesting economic design decisions in experimental equipment. Electricity for sample heating was expensive, but nitrogen for cooling was cheap.

It's official: TLS 1.3 approved as standard while spies weep

cray74
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Black Helicopters

Historical Revisionism or Mind Control Satellites?

The mass surveillance of internet communications by the US National Security Agency (NSA) revealed in 2013 by Edward Snowden,

In 2005-2007, major media groups like the New York Times, Reuters, BBC, and numerous others described the NSA's warrantless mass surveillance of the internet, phones, email, office gossip, and pillow talk. This incredible violation of privacy filled the evening TV news, internet websites, and newspapers.

After a few years of quiet, in 2013 Edward Snowden reminded the world that the NSA's surveillance was still happening.

However, most discussions I see today about the NSA's internet monitoring hail Snowden as the hero who FIRST told the world about it. It's like all the news coverage, ACLU lawsuits, and outrage of the late 2000s didn't happen and Snowden revealed something new. Maybe the NSA asked the CIA to use their mind control satellites to blank everyone's brains for a few years.

Non-rhetorical question: Is there some key difference between 2006 NSA internet surveillance and 2013 NSA internet surveillance that makes Snowden's revelation particularly novel? I feel like I'm missing something that makes Snowden different than all the earlier revelations.

Blast from the past: Boffins find the fastest exploding non-supernova star

cray74
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Particularly if it produced a gamma ray burst and if this was angled towards earth

Which wouldn't be a problem for Earth. GRBs are only threatening if they fire within a few parsecs of Earth, at which distance they could cause serious ozone degradation, a bit of a 'GRB winter' and some acid rain.

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