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Comment Re:"Clock parts" wired together in an adhoc fashio (Score 1) 814

Is the Moon a hoax bomb? If I claim it is a bomb, about to go off, is that now a suspected hoax bomb? Give me a break.

Anyone can suspect anything or anyone of anything. That doesn't make it a justified belief.

In real life we want justified beliefs.

The complete lack of anything resembling an explosive or detonator makes anyone suspecting it to be a bomb very stupid.

Submission + - Visual ARM1 - Celebrating ARM's 25th Anniversary (

trebonian writes: Today is the 25th anniversary of ARM Ltd., UK. To celebrate and honor their amazing work, we present the Visual ARM1, created in collaboration with some of ARM's founding engineers.

Designed by Sophie Wilson and Steve Furber before there was an ARM Ltd., the Acorn RISC Machine was the first of a line of processors that power our cell phones and tablets today. Unlike our projects based on microscope images, the Visual ARM was created from a resurrected .cif chip layout file, used under our license agreement with ARM. We also photographed one of the few ARM1 chips at very high resolution, and our photograph is featured at the Centre for Computing History in Cambridge.

Credit goes to ARM founding engineers John Biggs for inspiring the project, discovering the tape, and recovering a usable .cif file, Lee Smith for spotting the variable record format used to encode the file (an artifact of the VMS on Acorn's VAX that at first appeared to be widespread corruption of the file), to Cambridge University Computing Services for reading the Exabyte tape, and to ARM founder Dave Howard for help unraveling the VLSI CIF dialect. Our chip simulation and visualization was developed by Barry Silverman, Brian Silverman, Ed Spittles, and Greg James.

Comment Re:"Clock parts" wired together in an adhoc fashio (Score 1) 814

Yes, but to be a hoax *bomb* there would have to be a hoax *explosive*.

Where's the fake explosive in any picture of this device???

There isn't one.

Did he even claim it was a fake bomb at any time??? The answer seems to be: no.

It's all a load of rubbish, and the police knew that, which is why they let him go.

Comment Re:This'll be lost on new people. (Score 1) 167

They will think it is a spinoff of Lost. In space.

Oh man, that would (well could) be awesome!

A commercial spaceliner crashes somewhere. There's a radio broadcasting a mysterious repeating sequence of numbers, and a hatch leading to a Cold War era lunar base. And what the hell is a polar bear doing on the Moon?

Hmm, on second thoughts, maybe not.

Comment Re:Next remakes... (Score 2) 167

Technically "The Starlost" was by Cordwainer Bird, the pen name Ellison uses when the show (in his opinion) sucks.

Ellison's pilot script was adapted to a novel, "Phoenix Without Ashes", by (Nebula-winner) Ed Bryant, recently reissued. (Harlan is donating his share of the royalties to Ed to help cover some medical expenses.)

There's also a graphic novel version.

Comment Re:Not so fast (Score 1) 226

> Their tech works and they built it.

LOL, I don't think so.

This is the tech that keeps lithobraking and exploding when it's supposed to be landing on a barge. They've been trying to pin a landing since the first flight of Falcon 1. They're currently on Falcon 9.

Maybe they'll succeed one day, but the very high performance rockets they build are obviously *very* fragile.

And that's the problem with their approach, pure rocket reusables have to be super lightly built, and then it's very difficult to make it back down to the ground.

Comment Re:the interesting part (Score 1) 63

> Even the most devoutly religious would not actively wager money to put their faith to the test.

People do this kind of stuff all the time.

Many people wager their lives on their belief in a God, and... usually die.

George R. Price famously gave all his possessions to the poor; got evicted, fell into depression and then killed himself.

Comment Re:Not so fast (Score 1) 226

Actually, I once did a computer model of SpaceX-style reusability, and that's actually what my model showed me, that it would be extremely hard for SpaceX to get it to work.

But my modelling shows that Skylon ought to make orbit, and return and land safety with comparative ease, Their design is very insensitive to weight growth; and they actually have spare mass built into their design in case things are harder than they look.

But yeah, I do agree with you pretty much on the economics, that's the worst part of their design. But compared to the economics of the Space Shuttle... ;)

Comment Re:Not so fast (Score 1) 226

> Sure, at this stage of any project it's easy to be "looking at" very low costs. They haven't done anything yet. The nature of these kinds of projects is there are a whole bunch of costs, technical an regulatory, that aren't apparent until you actually start building something.

I don't agree. For example, the Space Shuttle estimates were about on the money. As in they said, the cost estimate is $X, but we'll need $1.2 X, to allow for obvious contingencies. President Nixon went: we don't budget contingencies, we'll give you X and then fund the overrun later. NASA: OK boss.

So actually, it cost what they said, but it looked to the rest of the world like an overrun.

And the Space Shuttle main engine was about as complicated as SABRE looks like it will be, maybe more so, it was an unreasonably complicated design.

And Reaction Engines actually have a careful design, with computer modelling of everything. That bodes well for a relatively straightforward detailed design and build. The X-33 had none of that, and when they got around to it, they found the horizontal stabilisation was total shit.

And the engine is particularly clever in that it works almost the same at all speeds; the precooler means that it doesn't care whether it's at ground level or Mach 5, the air behind the cooler is at the same temperature. That means, like a rocket engine, they can do almost complete testing when stationary. And the precooler also, they've already tested the precooler; it works fine. And the precooler was the most challenging bit of the whole system; it's something like half a gigawatt per tonne of cooling.

The take-home message is not that it's not a clever design, it's that most of the clever bits are easy to ground test. About the only bit they can't totally test on the ground is the aerodynamics of the aeroshell- but that was basically the same problem that the Space Shuttle faced and dealt with.

Comment Re:Not so fast (Score 3, Informative) 226

Actually, the Skylon group predicted that the X--33 wouldn't work. They said that the X-33 was too tail heavy. And fixing it would mess up the payload fraction. And they were right.

It's difficult to get your head around just how far ahead these guys have been for about 20 years.

The ultimate reason is that they built a computer model of launch vehicles, which they fiddled with until they got a plausible vehicle. Then they did a back-back comparison with a pure-rocket vehicle, and found that there was no big advantage. Then they fiddled around more, and out popped Skylon, and then they found it *seriously* beats pure-rocket vehicles; it's not even close.

Skylon is looking at costs starting around $500/kg and then going lower. SpaceX won't be able to get down to that.

The gent who wakes up and finds himself a success hasn't been asleep.