'Tenths of a Foot'? NASA Unit ???

I'd have thought that a mystical magical astrological guy like you would have more respect for the Babylonians, who more or less originated the 'art'.

They're the ones that gave us degrees, minutes and seconds.

(Or, wait, maybe you missed the smiley.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058

email: hobbs (atsign) electrooptical (period) net
http://electrooptical.net

Particularly dangerous are US short measure gallons vs true Imperial gallons and related metric conversions refuelling aircraft - a couple of fairly serious out of fuel incidents have been traced to that.

Most famously the Gimli glider:

"Tenths of a foot" is a particularly odd NASA unit though. "Inch" is shorter and much better known.

BTW A Tenth of a foot is just a shade under 1 attoParsec = 3.085cm.

Regards, Martin Brown

in

a

Yeah, I walked across that bridge back in the ~ mid/late 80's when the high field magnet lab was still at MIT. As I recall there were marks every ten Smoots, or something like that.

George H.

[snip]

Some humans are longer than others.

-- Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com

------------------------------------------------------------------ Real programmers don't draw flowcharts. Flowcharts are, after all, the illiterate's form of documentation. Cavemen drew flowcharts; look how much good it did them.

We use a current version of NASTRAN FEA (developed for NASA in the sixties) for mechanical analysis. Slinch*, anyone?

Fixed 80 column input lines in the "deck". Brings back memories of the venerable '029, it does.

• there's 12 slugs in a slinch.

I designed a PDP-11 to 029 interface once. Is everybody impressed?

John

That's why the French invented the Metric System.

Pecker-length sounds much more impressive in centimeters.

Lord Valve Connoisseur of Arcane Measurement Systems

Yup:

And until I heard of him, I didn't even know "Smoot" was a real name of a real person:

Cheers! Rich

Find a Democrat - they can rationalize anything! ;-)

Cheers! Rich

Sounds like a parrot with fingers.

Cheers! Rich

Phil Hobbs schrieb:

Hello,

1 pc = 30.856776 ? 10^15 m 1 ft = 0.3048 m 1 attoparsec = 0.030856776 m 1 decifoot = 0.03048 m

error 1.2 %, nearly perfect. But if we should not use metric units, what is about the use of metrich prefixes like atto? ;-)

Another way to express the relation:

1 parsec = 100 Petafoot

Bye

Powers of 10 have a physiological origin, so that's okay--it's just those rotten atheistical revolutionary French dogs He doesn't like. ;)

(Of course it's a minor problem for my argument that the original definition of the metre was something like 10**-7 of the length of the meridian of Paris, measured from the equator to the pole. But of course both ends of that line are at sea, like so many subsequent French initiatives.)

1 parsec ~= 100 petafoot, I like that. So much cozier than 206265 (and change) Astronomical Units.

Cheers

Phil Hobbs

t e

nd

And 1 nano-c-second or c-nanosecond =3D 11.8 inches ( c is the speed of light in vacuum)

Good point--that's a rule of thumb I use all the time. (It's 1.5 nanoseconds per foot in coax or optical fibre.) Of course nowadays a nanosecond is a pretty human-sized unit--or, rather, canyon-sized, as John L insists. ;)

Cheers

Phil Hobbs

Well, I am, John.

Direct fan-fold punched paper tape to 80-column punched cards. What a concept!

In fact, if I could transfer my old DECtape reel to paper tape I could transfer my last college project to a medium I couldn't read... Oh, wait. That's what I have now.

Thanks for the memory.

Frank McKenney

-- Looking back now, I think I can understand the basic reason why we had to move so slowly. In a democracy, a mere majority is not a sufficient foundation when drastic and far-reaching action is necessary to protect the nation in time of peril. At such a time, the people as a whole must stand solidly together; they cannot defend their country and their liberties with sharply divided counsel. Thus, a bare majority was not enough for the destroyers-for-bases deal, and even less so for Lend-Lease six months later.

The majority had to be so strong and so determined that the will of the country was unmistakable to every citizen regardless of his own views. To have acted suddenly without thorough discussion might have left a dangeous cleavage among the American people at a time when unity among us was more important than ever before. Days and weeks of open debate were needed before there was that solid basis of unity in the minds and hearts of the poeple necessary for the momentous step we were about to take.

This is not the method by which a dictator builds an army for aggression. But it is the method by which the people of a freedom-loving nation unite behind their leaders to defend themselves against dictators, and eventually to create the overwhelming power necessary to crush them. -- Edward R. Stettinius / Lend-Lease: Weapon for Victory (1944)

-- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney aatt mindspring ddoott com

Punched cards were a revelation, after paper tape. It was so easy to edit. You could copy a subroutine onto another deck of cards, highlight the edge in some color, and voila, modular code reuse!

I patched MACRO-11 and Focal-11 to read cards.

John

But, doesn't that bring us full-circle? Isn't 206265 simply the tangent of

1/2 arc-second?

Thanks, Rich

It's 360*3600/(2*pi), i.e. the number of arc seconds in a radian, and is a nice easy number to remember. The sine and tangent of one arc second are both very close to the reciprocal of this number.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058

hobbs at electrooptical dot net
http://electrooptical.net