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NASA Video Shows What It's Like To Reenter the Earth's Atmosphere

stjobe Re:Re-entry is done wrong (72 comments)

They are "doing it right", there's just no way to do it the way you seem to think it should be done because of the speeds involved and the physics of orbiting.

Low Earth Orbit is only achievable with a speed of roughly 7.8 km/s (17,450 mph, 28,080 kph). Compare that to our regular "smooth controlled flight just like regular flight", with airliners topping roughly 600 mph (1,000 kph), and the fastest air-breathing manned aircraft ever made (the magnificent SR-71) only approaching 2,200 mph (3,500 kph).

The mechanics of orbiting says that to keep a stable orbit you keep a stable speed; if you increase speed you go to a higher orbit, and if you decrease speed you go to a lower orbit. So to get out of orbit we need to slow down.

So you're starting re-entry from a speed roughly ten times faster than a M-16 bullet - at these speeds any interaction with any kind of atmosphere is going to create "major high temperatures", but the physics say that you can't slow down without lowering your orbit and hence entering the atmosphere.

So we're in a bit of a bind here; we're orbiting at 28,000 kph, and we need to slow down to about a tenth of that to even have a chance of "smooth controlled flight" - but as soon as we slow down, our orbit lowers and we hit atmosphere, creating "major high temperatures" because of our speeds.

It should also be noted that it took the better part (70-90% or so) of our launchpad mass to get us up to this speed, and we simply do not have enough fuel to do much of any brake thrusting - the Tsiolkovsky rocket equation is a harsh mistress indeed.

So you see, it's not really that they're "doing it wrong", it's that you don't understand the problem. To be up there in the first place means you have to go really, really fast, and that means re-entry cannot be done "slowly, [...] gliding down gracefully", because as soon as you start to slow down your orbit decays and you start re-entry.

yesterday
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Small Bank In Kansas Creates the Bank Account of the Future

stjobe Re:Unless it has support for Bitcoin... (156 comments)

Not every bank. Unlike the US, banks in other parts of the world aren't in the dark ages. Sending and receiving money via your bank account can be done instantly, even from your smart phone (no Apple Pay or NFC software required, just email or whatever other system you choose to use from the various options the banks offer).

When I (living in an EU country) need to transfer money to someone, I
* start up my bank's app (for me, it's an Android app, but it's available for iPhone as well) and log in
* ask the person for their bank account number (or pick it from a list of previous transfers)
* enter the amount
* press "send" and validate with my electronic ID.

It takes all of ten seconds, and there's no fee involved. The money usually shows up in the receiver's account immediately.

When I get a bill, I use the same app to OCR it (using my phone's camera), pick an account to debit, and store it to be processed on a date I choose. Takes about ten seconds per bill, then I send them all at once to the bank with one security validation.

I haven't been at a physical bank location in seven years, and the only reason I went there then was to get a mortgage. I haven't been to a physical bank location to pay bills this century.

So yeah. If this is news for Americans, you really do live in the dark ages of banking.

5 days ago
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Judge Rules Drug Maker Cannot Halt Sales of Alzheimer's Medicine

stjobe Re:Can you say... (263 comments)

you are effectively requiring someone to act against his will and work for the company without being able to quit--which is akin to slavery.

Isn't that the whole idea behind capitalism in the first place? Make people act against their will and work for a company without being able to quit? Sure, you can quit working for a specific company, but it's a bit harder to quit working for any company.

There's some delicious irony in forcing the company owners into the same shoes as their employees - I approve of your idea :)

about a week ago
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Excuse Me While I Kiss This Guy: The Science of Misheard Song Lyrics

stjobe Re:My personal favorite of the past few years... (244 comments)

Not sure I'm 100% committed to this rock'n'roll lifestyle:

"I wanna rock'n'roll all night,
and part of every day"
  - KISS

about two weeks ago
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Berkeley Lab Builds World Record Tabletop-Size Particle Accelerator

stjobe Re:Duh! (90 comments)

42.2 Joules, actually.

But since that energy was delivered in 40 femtoseconds, they multiplied the two values and said it is a petawatt laser.

Funny what a wikipedia search might teach you :)

about two weeks ago
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Trains May Soon Come Equipped With Debris-Zapping Lasers

stjobe Re:They're leaves. (194 comments)

They're not "just leaves".

I thought this looked familiar, and sure enough, google turned up this article from 2007 about the system and the guy who spent eight years and 5 million GBP to try to solve it.

"Every time a train runs over a pile of leaves, they are squashed into a hard, black, shiny, Teflon-like substance that makes it more difficult for trains to slow down and stop."

"Rofin-Sinar created a monster. The final version of the laser railhead cleaner contains two lasers capable of producing 2kW each. The pulsed energy is channelled via a fibre optic, which delivers a round beam in a straight line across the rail.
The pulsed beam hits the rail 25,000 times per second. The leafy mulch absorbs each 5,000C pulse of light, causing it to heat rapidly, expand and lift off the rails. Tests have found that the laser cleaner also works on oil, grease, ice and other problematic substances."

about two weeks ago
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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

stjobe Re:PBS had a documentary... (103 comments)

Some huge trucks still have things based on variable transmission technology, so the entire gearbox doesn't have gears but just slides into the most convenient gearing automatically. They've been around for decades. And they work by using a strong belt that can slide up and down a conical shaft. I kid you not. Every few years, they are re-invented under another brand / patent / material and actually do quite a good job. But they are still considered specialist parts because we can't overcome their weaknesses.

My 2012 Toyota iQ most definitely isn't "some huge truck", and its Super CVT-i transmission most assuredly doesn't have any "weaknesses" that needs to be overcome, nor is it considered "a special part" - it's just another option on the options list.

In fact, after having driven one for three years, I'm not sure I'd want to have a "regular" automatic gearbox, and I'm absolutely sure I don't want to go back to manual. Rush-hour traffic no longer feels like sitting in a pedal car...

about two weeks ago
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Intel Processor Could Be In Next-Gen Google Glass

stjobe Re:Good job Intel (73 comments)

However, someone coming into a bar recording everything (both visually and via audio) that should be private [...] being constantly recorded in a place where privacy is expected

I don't know what kind of bars you have where you live, but around here bars are public places. In fact, they're usually called "pubs" (short for "public house", apparently). There's no more expectation of privacy at the bar than in a park or other public place.

With Google Glass, at least you see them recording; the cellphone that's on "record" two tables over is just lost in the clutter...

about three weeks ago
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Two Google Engineers Say Renewables Can't Cure Climate Change

stjobe Re:Fat chance (652 comments)

No, because there's almost half a decade worth of FUD been spent on making people equate "nuclear" with "bad."

"Half a decade"? If you mean "half a century", you're about right.

about three weeks ago
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Two Google Engineers Say Renewables Can't Cure Climate Change

stjobe Re:Is Nuclear going to be acknowledged? (652 comments)

Google "breeder reactor" and "thorium reactor".

Engineering-wise, nuclear waste is basically a solved problem. It's political and economical factors that are making it a problem still.

about three weeks ago
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Rosetta's Philae Probe To Land On Comet Tomorrow

stjobe Re:How f!@#$%ing cool is that?! (74 comments)

"Sticks and stones may break my bones, but words can really hurt me".

about a month ago
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David Cameron Says Brits Should Be Taught Imperial Measures

stjobe Re:And many, many more (942 comments)

In the EU, if you're serving by the pint, you have to either have glasses with fill lines, or pumps that are certified as dispensing a pint of liquid per pull. It's actually illegal to do otherwise. See Pint glass

about 3 months ago
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Study: Antarctic Sea-Level Rising Faster Than Global Rate

stjobe Re:unfair policy (302 comments)

It's getting its compensation.....an Arctic Ice Cap that has expanded by 41% in the past 2 years. Most ice up there since 2006. Ironically, not reported here....
I guess anything goes to advance the global warming scam.

Sure, it's expanded by 41% in the last two years. What you fail to mention is that 2012 was a record low.

Guess that didn't fit into your "global warming scam" world-view?

about 4 months ago
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XKCD Author's Unpublished Book Remains a Best-Seller For 5 Months

stjobe Re:XKCD (169 comments)

It's not actually an acronym. It's just a word with no phonetic pronunciation -- a treasured and carefully-guarded point in the space of four-character strings.

http://xkcd.com/about/

about 4 months ago
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How the Ancient Egyptians (Should Have) Built the Pyramids

stjobe Re:Corroborating Hieroglyphics? (202 comments)

simply stacked the blocks

I think this is the part you mistakenly think is easy.

There's roughly 2.4 million stones in the Great Pyramid of Giza, some of which weigh up to 80 tons. "Simply stacking" them is anything but.

about 4 months ago
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Net Neutrality Is 'Marxist,' According To a Koch-Backed Astroturf Group

stjobe Re:What's so American (531 comments)

Without any mod points today the next best thing I can do is to say "Bravo AC, bravo!" and hope someone with mod points mods you up.

It always amazes me that the McCarthy-era Red Scare still lives and breathes in 21st Century America.

about 4 months ago
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No, a Huge Asteroid Is Not "Set To Wipe Out Life On Earth In 2880"

stjobe Re:Actually... (123 comments)

Suppose somebody built a nuclear power plant next door to you that had a 1 in 4000 chance of going critical on any one day. That's a median of 11 years, right?

Yeah, sure. But the thing here is that it's not a 1 in 4,000 chance of this asteroid hitting us every day; it's 1 in 4,000 that it'll hit us once. 800-odd years from now.

1 in 4,000 is a small enough chance to be a virtual certainty over a few hours for events happening once a second - does that mean anything at all to a 1 in 4,000 once-in-a-lifetime chance? No. And this event is not even a once-in-a-lifetime event; it's once-in-several-tens-of-lifetimes.

Or to put it another way: People suck at probability assessments.

about 4 months ago
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Crytek USA Collapses, Sells Game IP To Other Developers

stjobe Re:Not Getting Paid (121 comments)

1. "Taxpayers like me" include you, me, the other employees at said company, and everyone else that pays taxes - the company in question and all other companies as well. The money comes from taxes already paid.
2. The sums involved wouldn't make a noticeable difference to your taxes since it's split several million ways.
3. How is protecting the employees of a failing company "propping up" said company? Either it's bankrupt and is going down, or it can recover and then has to pay back the money the government spent on employee salaries.

On a side note, I find it quite amazing that the McCarthy-era "red scare" still lives and thrives in 21st century America...

about 5 months ago
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Crytek USA Collapses, Sells Game IP To Other Developers

stjobe Re:Not Getting Paid (121 comments)

Now where did I define "employee protection" as "employees working for free"?

Oh, that's right, I didn't. I even gave an example of how strong employee protection made sure I got paid even though my company couldn't pay me.

In the example I gave, the government paid our salaries while the company negotiated with its creditors; the company then had to pay that money back to the government. I never missed a paycheck; the employees were indeed protected.

Had the company failed in its negotiations with their creditors, it would have had to declare bankruptcy and the state would have covered our salaries during the bankruptcy proceedings. After that, we would be on our own.

Luckily for me, the company succeeded in reducing or cancelling their debts and made a full recovery (which was actually the whole point of the example, to answer the question "do companies recover from a situation where they're unable to pay salaries for a period of time" - yes they sometimes do).

about 5 months ago

Submissions

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Author raises $1m to self-publish webcomic book

stjobe stjobe writes  |  more than 2 years ago

stjobe (78285) writes "A runaway success for Kickstarter and Order of the Stick author Rich Burlew; not only did he raise more than 2000% of his goal, he broke a few records in the process:

"Author and illustrator Rich Burlew launched The Order of the Stick online in 2003. Following the comic fantasy adventures of a collection of stick figures in a role-playing game world as they struggle with enemies and the rules of the game, much of the story is available online for free, but Burlew also began self-publishing parts of it in paper format in 2005. When the costs of keeping it in print proved too high, Burlew turned to Kickstarter following repeated demands from readers, launching a project in January to raise the $57,750 he needed to rerelease the books in print.

Yesterday, he closed his fundraising project with 14,952 backers and $1,254,120 raised, making The Order of the Stick Kickstarter's most funded project by a single person ever and the most funded creative work the site has ever seen.""

Link to Original Source
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Schlock Mercenary turns 10

stjobe stjobe writes  |  more than 4 years ago

stjobe (78285) writes "Every day now for the last 10 years there's been an new comic up over at Schlock Mercenary. The artist, Howard Tayler, compares it to some other things that's been happening over the last 10 years:

It is older than half of my children.
It is older than my car.
Depending on how you count, it's the longest I've ever held the same job.
I've spent almost a quarter of my life on this.
I've spent more than half my married life on this.
I've drawn 3653 strips, for a total of around 15,000 panels.
There are another 20 strips you still haven't seen (plus a kajillion or so I still haven't drawn.)
I've used enough kneaded eraser that the 'waste lump' of stuff that is too dirty to erase with is twice the size of my fist, and I've thrown away at least twice that much.
I've gone through about 10,000 sheets of legal sized paper.
I've gone through about 500 pens. Each of those set me back around $2.50.
In all that time I've only used five different mechanical pencils. I still have the first one, the second one, and the fifth one.

"
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stjobe stjobe writes  |  more than 7 years ago

stjobe (78285) writes "Sydney Morning Herald reports:

Australian and US scientists successfully launched a supersonic scramjet engine at an Outback test range Friday, as they work on a device that could revolutionise air travel.
The researchers said a rocket carrying the scramjet reached speeds of mach 10 — ten times the speed of sound — after blasting off at the Woomera range in South Australia Friday.
They said it reached an altitude of 530 kilometres (330 miles) before the scramjet was successfully deployed following re-entry to the Earth's atmosphere.
Australia's Defence Science and Technology Organisation (DSTO) said it was believed to be the first time a scramjet had been ignited within the Earth's atmosphere.

Google news has many other sources as well."

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