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Comment: Re: 9 whole billion? OUTRAGEOUS! (Score 1) 124

by KJSwartz (#49352891) Attached to: GAO Denied Access To Webb Telescope Workers By Northrop Grumman

... and it would look like the underfunded and slap-dash POC that would require Orion to make repair flights, if you don't skip town first. It takes people at all stages of the production phase to deliver a valuable scientific instrument, and you are the only one who wants to send up an Apple I.

Comment: Re: Backpedalled? (Score 1) 740

by KJSwartz (#48967765) Attached to: New Jersey Gov. Christie: Parents Should Have Choice In Vaccinations

I was getting lost in the number of cowards responding to this thread. Thank you for giving a non-Jeckyl/Hyde face to this discussion. Perhaps it is time to infect 1000s of lab monkeys with measles to prove the argument by dissection. The anti-vaccine people would have their proof, and the science would be demonstrated.

Comment: Re: A precision deflation (Score 1) 239

by KJSwartz (#48955421) Attached to: NFL Asks Columbia University For Help With Deflate-Gate

Yuck - your math was correct, but let's simplify your answer a bit.

You started with a pressure of 27.2 PSI at room temperature, and arrived at nearly 26 PSI as the field pressure, with a realized loss of 1.2 PSI. That's an impressive loss, but the other team's footballs would have suffered a similar effect.

You have my admiration, sir or madam. Well done!

Comment: Re: Classic science fair project & shrinky din (Score 1) 239

by KJSwartz (#48955333) Attached to: NFL Asks Columbia University For Help With Deflate-Gate

I was going to savor the victory, but its not fair to you...

If its not coefficient of thermal expansion, then what? Nerf might be comparable to "shrinky-dinks", but not League sanctioned footballs - there's not enough hard rubber to make an appreciable difference. Remember holding a fully deflated ball? Really not much substance to them.

Comment: Re: It's more than Ideal Gas laws (Score 1) 239

by KJSwartz (#48954903) Attached to: NFL Asks Columbia University For Help With Deflate-Gate

Coefficients of expansion
Aluminum    ÂÂ12.3
Acrylic        Â42
Rubber, hard    Â42.8    (10-6 in/(in degF))
Steel        Â6.7

Rubber expands almost 7 times faster than steel and nearly 4 times greater than aluminum. Are you sure Columbia isn't just a liberal arts college?

Comment: Re: It's not the gas... (Score 1) 239

by KJSwartz (#48953299) Attached to: NFL Asks Columbia University For Help With Deflate-Gate

It's refreshing to watch everybody grapple with the nuances of basic physics principles, only to discover they don't understand them so well.

1) was the same pressure gauge used for both measurement? If not, who calibrated the precision instruments used by the referees?

2) 1 ATM = about 14.7 PSI at STP. Where was it the patriots were playing?

3) 1 ATM = about 14.7 PSI at STP. These balls were inflated to 27.2 PSI with a properly calibrated pressure gauge, otherwise the quarterbacks are grappling flopping pigskins.

4) height above MSL (mean sea level) also affects the gas chemistry, and gas mixture does drastically impact pressure. Inflating tires with (relatively) inert nitrogen is now all the rage. What if somebody was inspired to use a unconventional mixture?

It's terrific that people are trying hard to puzzle out the mechanics. Perhaps some trust will come out of this with future climate change discussions.

Comment: Re: GPS launches also go from Canaveral (Score 1) 219

That is a beautiful thought. Any of those remote telemetry stations in military bases? Had NASA been in charge of GPS, we wouldn't have destroyed the plans of the original satellites, nor the higher precision add-ons. We are out of spare GPS satellites and a replacement has yet to be launched.

Come to think of it: where are the GOES weather satellite replacements as well?

Who goeth a-borrowing goeth a-sorrowing. -- Thomas Tusser