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Comment: Laser Jammer "Source" versus physics :-) (Score 1) 1 1

AbramPlace744 http://slashdot.org/~AbramPlac... mentions http://laserjammer.org/ as a source, but the source seems to be confused about how radar gun technology works.

One of the biggest differences in the way that the guns work is that radar guns emit a pulse of sound (or radio frequency transmission), which travels at a rate of about 1000 feet per second. [Implied here is that radar guns either are AUDIO, and/or radio propogates at 1000 fps] Light, on the other hand, moves much, much faster. Light-waves travel at a rate of around 984,000,000 feet per second.

Comment: "Designated Idiot": A useful classroom function (Score 1) 255 255

We discovered a wonderful use for the warm-hearted student who was never going to get an A.

When someone was too embarrassed to ask a "stupid" question, we would have the "Designated Idiot" ask it. The professor might sigh a bit, but would always give a more complete answer, so the rest of us understood the material more completely.

And there were benefits all around. In a series of classes, we had a professor known to subjectively ding student's grades for "dumb" questions. Our "Designated Idiot" kept the class grades a bit higher as a result. In this class and others, we noticed that our "Designated Idiot" tended to get a higher letter grade than the test scores might have suggested.

In many cases, while it interrupted the flow of the the class, the professors saw the benefit in quizzes and tests on the topics. When the "dumb question" had been asked, the material covered was retained far better by the class.

So don't shoot the idiot. Find them a role that helps everyone!

Comment: Re: We had a better system. (Score 1) 246 246

We had a better system. Launched all its satellite payloads pretty well. Only one Tracking and Data Relay Satellite was lost. Human cost was 14 of our best and brightest people over the launch system's lifetime. See: http://en.wikipedia.org/wiki/STS-51-L and http://en.wikipedia.org/wiki/STS-107 .

NASA, and now picking up the ball DOD, decided to try and eliminate the human cost. The result, http://en.wikipedia.org/wiki/Boeing_X-37, just had a successful launch. Originally, it was to be launched from the shuttle (a shuttle within a shuttle), but the Columbia disaster changed that.

Other ideas still proceed, but slowly...

Comment: Maneuvers to save Huygens probe data... (Score 1) 116 116

One of the keys to Cassini's success has been flexibility. Using fancy flying, NASA/ESA were able to save the payload Huygens probe mission, which had an almost fatal communications flaw.
The story has a hero, Boris Smeds, a Swedish radio engineer for the ESA, who pushed and pushed because he found out something was very wrong with the Huygens payload to be launched from Cassini probe.


Slashdot covered this well and humorously. See substitute links provided for 6 years of bit rot on URL's :-)
Saving Huygens

"Titan Calling: How a Swedish engineer saved a once-in-a-lifetime mission to Saturn's mysterious moon"

and The story behind "Titan Calling"

For completeness sake, here is a NASA/JPL paper on "What we can do to fix the problem"
Resolving the Cassini/Huygens Relay Radio Anomaly

The paper's "lessons learned" are particularly important:
  • Spacecraft subsystems must be tested to all of their requirements before launch (this would have helped Hubble Space Telescope, too).
  • Keep engineering model and flight spares operational throughout the mission.
  • Documentation of Spacecraft Hardware and testing.
    "It is important to keep proper documentation of all tests so this information is available when something goes wrong."
  • Never intentionally throw away data in a deep space mission.
    Spacecraft systems need to have an appropriate level of reconfigurability in flight. "This anomaly would have been easy to solve if there has been even a modest amount of reconfigurability in the PSA."

Doppler Shift? What is this Doppler Shift thing you speak of? :-)

Comment: Re:Come on Slashdot (Score 1) 123 123

"Turning Leonardo into a permanent module will take some work, said NASA Payload Manager Joe Delai. "Once it returns from this flight we will beef up the external shield and change things internally to become a permanent module. It will be about a four month process to get it ready."

Thats why it will be re-launched in September this year. And when it is relaunched and made a permanent module it will become their 'man cave'.

Permanent: means it lasts until ISS de-orbit in 2016. Yup, idiocy still planned. See: (In glorious PowerPoint)

http://www.nasa.gov/pdf/386764main_09-15-09_Human_Spaceflight_Testimony.pdf

http://titan04.ksc.nasa.gov/shuttle/nexgen/Nexgen_Downloads/378555main_02-Sally_Charts_v11.ppt

Or just search via Google: for iss +"de-orbit" site:nasa.gov

http://www.google.com/search?hl=en&q=iss+%22de-orbit%22+site%3Anasa.gov

Comment: Re:there's a few useful bits of software already (Score 1) 146 146

In another instance,

Nicholas Harbour, who at the time was working for the Department of Defense Computer Forensics Lab (DCFL)

wrote a loving modified dd that writes to multiple files and streams to multiple programs at the same time. The program, dcfldd, also introduces the sorely missed VERIFY operation, and even block-by-block hashes, ( dcfldd Man page)

Maybe someone will combine this with dd_rescue, ddrescue and dd_rhelp to make the ultimate "Convert and Copy" utility :-)

Ah and I can dream of SCTP support too :-)

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