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Comment Re:Have they studied physics? (Score 1) 438

And where does the payload land on the 1-in-100 launches that the orbital insertion motor fails?

Pretty much the same place as the payload on a current launch if its insertion motor fails. Were you under the impression rocket-based launches don't use insertion motors?

Not quite. Current launch technology (read: rockets) are powered through much of the atmospheric flight. MECO occurs outside the atmosphere, and the craft's flight path takes it over uninhabited areas for the thousand KM until it is outside the atmosphere. Therefore, at no point is the vehicle on a trajectory such that if it looses power, it will intersect the Earth in an inhabited area. The balistic tragectory of the 'Slingatron', however, does bisect the Earth at roughly (due to atmospheric drag) the same place where it was launched from. Also, one needs to take into account the possibility that the payload will leave the muzzle at lower than expected velocity. Thus, an entire great circle of the Earth, several tens or hundreds of kilometers wide, potentially falls within the craft range.

The insertion motor isn't necessarily a single-purpose item; for example, the Shuttle used the same motors for insertion that it used for the rest of its on-orbit maneuvers...but one way or another, you either insert or you come back down.

Yes, I am aware of the functions of the OMS. And I believe that there was an abort mode for failure of the OMS, though it was not an OTA.

Comment Re:Have they studied physics? (Score 1) 438

TFA points out that it will have to have an orbital insertion motor on board.

And where does the payload land on the 1-in-100 launches that the orbital insertion motor fails? At what speed, with how much kinetic energy, does it hit?

Note that current space vehicles, even man-rated ones, have about a 1-in-80 failure rate.

Comment Re:Huh? (Score 2) 241

Or a PS/2 connector that the user tried to force in by twisting motion instead of just looking at the end to determine which way to put it.

I once watched in horror as a Post Office clerk did that to her keyboard (nice Cherry switches it looked like) while I was in line. She was forcing and twisting for a good ten seconds before I snapped and stopped her. The pins looked like my daughter's braided hair. I was able to straigten them out by sliding a mechanical pencil without the lead over each pin and carefully bend it back to place.

Comment Re:Forgetting the 'where' clause (Score 1) 641

Running an SQL update statement without a where clause and seeing '47,982 rows updated'.......bonechilling

I've done this. Now I talk to the interpreter like this:
where ^a delete from table ^e name='bill';

Now my biggest fear is getting the ln and tar order of arguments correct, lest some huge directory get replaced with an empty tarball or going-nowhere link.

Comment Re:Who guards the guards? (Score 1) 407

Then the only question remaining is whether we should trust you.

Maybe you can, maybe your can't, but there is nobody that you can trust _more_ than Eric Paris. If the NSA has gotten Eric's compliance, then there is no where else for you to turn: not to Microsoft, not to Apple, and not to any of the BSDs.

Comment Re:Real threat or open question? (Score 1) 407

Hi Eric! As much has I appreciate your competence and your attention to detail, is it not possible (or even plausible) that insidious code such as that found in The Underhanded C Contest might have been passed in under your nose?

Of course, it is reasonable to assume that the SE Linux code would be especially vetted for backdoors, and thus other areas of the kernel might make for less-eyes-looking-for-issues cover for a backdoor. But considering how much code goes into the kernel, is it not possible that some innocuous-looking code may have gotten through?

Of course, if SELinux or any other component is compromised (or the hardware), then it is safe to assume that _no_ operating environment is any better off.

Comment Re:Amazon (Score 1) 100

I just signed up with these guys about a year ago:

I'm stupid happy with them. If you want, I can set you up with my own reseller account with them. I won't even charge you for the month or so while you get stuff up and running. Once you're happy with the way things are going, I'll charge you cost for the server space, if it is a non-profit that I agree with. Who is the non-profit?

I'm also a developer by trade, so though I won't commit to doing 'free work' I will happily help with some technical issues or advice if need be.

Comment Re:The fastest way to Mars... (Score 1) 285

Moon-LMO shuttle

LEO: Low Earth Orbit

That is a nice dream, but Low Moon Orbit does not exist. The moon's gravity is too lumpy for that. You either land on the moon or crash on the moon, you don't orbit it. At least, not for more than a few weeks and even that demands considerable fuel expenditure in the form of station-keeping.

Comment Re:Unit Tests (Score 2) 254

If possible, I would try writing unit tests for the existing code. This tests your understanding of what you are reading and will come in handy later if you change the code. If unit tests already exist then I suggest that you read them since they will tell you the intention of each function.

Unit tests are a lot like documentation: they will tell you what the code is _expected_ to do. (Not what the code actually _will_ do, especially in corner cases). Thus, if you are already digging in to see what any section of code is doing, document what you've found: write a unit test.

Submission + - German dam bursts (

dotancohen writes: Thousands of people have been evacuated to safety in eastern Germany after a dam burst on the swollen River Elbe and farmland was flooded in an attempt to spare towns, with meteorologists forecasting more rain.

In Magdeburg, one of the oldest cities in eastern Germany and a regional capital, some 23,000 people were asked to leave on Monday as water levels in the Elbe rose to a record 7.48 metres — about 5 metres above normal and surpassing the level reached during devastating floods in 2002.

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