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Comment That was fast! (Score 2) 404

AFAIK, the FBI is still waiting to obtain and decrypt all of the shooters electronic devices. Comey's announcement comes after Obama confidently saying the same thing only this morning. I would not normally expect such a proclamation THE FIRST WORKDAY AFTER THE EVENT. Normally an exhaustive forensic effort would result in some bureaucratic report being generated about a year from now.

Comment Re:Potetntial Hack (Score 1) 267

I love the fact that the last four digits of the above (3741) post happen to match an IBM system from 1974 that used the same diskettes described in TFA. The floppy was formatted to the standard described in the 3740 format. This format was later used on the first CP/M computer systems. My first real computer (a Ferguson Big Board II) used Shugart 850 8" floppy drives that used this same disk format. My second computer (an IMSAI 8080) used 851 drives that supported double sided floppy diskettes.

The standard 3740 diskette held 241kiB of data and was very slow. We've come a long way since then.

Comment Summary Error, Article Error (Score 1) 101

I know nothing about the specifics of this mission, but I do know something about spacecraft.

The summary says the star tracker didn't work in "an area of low magnetic flux" (the South Atlantic Anomaly). The true issue is that the SAA is a high radiation area and the radiation caused an SEU in the star tracker. The Scientific American article was a bit mixed up about dumping the momentum stored in the reaction wheels. The text is a bit jumbled, but I believe the article was referring to magnetic torque rods which produce a force vs. Earth's magnetic field, but they only work if the spacecraft is stable. The spacecraft was never stable because the IRU (gyroscopes) provided erroneous information. In the end, the ACS issue (probably a sign error) is what killed the spacecraft.

Comment Why You Don't Adjust Data (Score 1) 446

Well, I can understand why the above would be modded troll (-1). I did not cite any source for my affirmation that the records are being modified. I guess it's too much to expect people to check it out for themselves.

Nobody is denying that the records are being modified. The only contested issue is whether or not the modifications are correct or justified.

Here is a timely article explaining the fallacy of modifying scientific source data.

Comment Re:400 times more power per gram? Great news! (Score 1) 135

It actually DOES work in some cases. Many spacecraft presently use triple junction GaAs photovoltaics with ~30% efficiency. Typical single junction Si cells top out at around 12% efficiency. Quad junction cells exist (~43% efficiency), but I'm not aware of any that have flown yet (which doesn't mean they haven't).

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