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Mars Orbiter Lost Over Metric Conversion Error
Buxley writes "NASA is reporting that they've found the likely cause for last week's loss of the Mars Climate Orbiter. It seems one of the engineering teams was using English units of measurement while another team was using Metric units. Getting this straight is rather important when designing navigation sytems for interplanetary spacecraft, one would think." A lot of people sent this one in; thanks to all. And if this event doesn't prove that it's time for the U.S. to go 100% metric, I don't know what will. Oy!
It is much easier to imagine and understand what it means to say "I am six feet tall" than it is to say "I am one hundred and eighty three centimeters tall" or "I am one point eight meters tall".
/.) for it, the Metric system does work extraordinarily well in "everyday" situations.
The hell you say. It may be easier for you because you have been raised used feet and inches, but there is definitely nothing intrinsically more intuitive about it.
The Fahrenheit scale uses (aproximately) the normal human body temperature as 100. Since most real world temperatures (like weather) are done around this temperature and above 0 (the temperature of salted ice), the Fahrenheit scale is a more convenient scale for human life.
Again, I take that you mean a more convenient scale for Americans. From my point of view, the Fahrenheit scale is a counterintuitive horror. After ten years of exposure to the Imperial system, I can deal with inches, miles, gallons and pounds, but I still can't get my head around Fahrenheit. Besides, the most significant transition point in "the real world" is that of liquid water to ice. The Celsius scale springs from this. How much more intuitive you want to get?
I guess we all have our cultural biases and try to justify them, but from a standpoint of making sense, the Imperial System doesn't have much of a leg to stand on, definitely not in the 21st Century. Take my word (and that of all the other Europeans in
"Be nice, veer left, and never stop thinking" Iain Banks - Walking On Glass
Hello?? This happened in England a few decades ago. The metric system was not in widespread use until the last few decades. If most of the world can do it, I'm sure Americans can too, unless they have a problem with the "not invented here" syndrome, which I believe they do.
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Don't you realize that all your pseudo-facts are completely biased by your education?
The English system is focused on the idea that humans only want to / can deal with multiples of two or three things comfortably.
Then metric wins, as there is only 1 "thing" to measure against, and 1 scale. Orthogonal design. Good.
It is much easier to imagine and understand what it means to say "I am six feet tall" than it is to say "I am one hundred and eighty three centimeters tall" or "I am one point eight meters tall"
Guess what I am 1m85cm tall and I "know" what 1m50cm tall means or 1m90cm tall. Why? because I have been raised in a metric country. 6ft. 1in doesn't mean anything to me.
The English units of volumes are done in binary (and a couple, like tablespoons, in ternary). One foot equals twelve inches and one gross equals 144 objects because these are useful numbers: lots of other numbers divide them. Humans don't do floating point arithmatic with great ease. Use a system that bumps everything up into integers. /SARCASM
Are metric-raised people superior then ? Because metric-raised handle non-integeral measures quit well, thank you. Ten has always been a stupid choice for the base of a number system.
I would gladly agree with you but for a small detail: every day numbers are expressed in base 10, which makes handling a base-10 measurement system so much easier. Base 10 is drilled into everyone's mind since their kindergarten. SARCASM and yes base 60 is so much easier, no wonder it's so easy to teach children how to read a clock !
[Comparisonn of Fahrenheit versus Celsius]
Again, you are biased by your upbringing. Metric-people have none of the problems that you attribute to the Celsius scale. And I boil water multiple times per week, I have a very good understanding of what 100C means. I have ice in my freezer and understand what 0C means. I certainly do not have a good perception of my body temperature, so 100K does not mean anything to me.
t ranks right up there with the prostate as one of the fundamental ways in which humans are "designed". We should've been built with 12 fingers instead of 10. We'd all be much better off.
Yeah right. We'd be better off without morons like you.
Reality check: metric is as easy to use (or easier) as english. You are in denial because of your education, stop deluding yourself with BS explanations of why english is "superior" or "more natural".
It turns out that a thousandth of an inch is an extraorinarily usefully sized increment when dealing with machined parts. (Not to mention that when you need to check clearances, a one mil shim/feeler gauge is as close as the cellophane cigarrette wrapper from the nearest smoker - try it for yourself. No idea what thickness foreign cigarrette wrappers are, but I'd chortle if they're .001"!)
.39 thousandths, and makes accurate dial calipers, etc. more difficult and expensive. This also results in a unit that does not line up well with engineering notation, where exponents are multiples of three to help avoid errors - to fix this you either need to write .001" as .0254 mm or 25.4um (micrometers) - difficult because it's notoriously difficult to type the proper "mu" on non-greek keyboards, and micrometers are both little bitty and the device you use to measure small things with. On top of that, all of these folks "think" clearances and allowances in thousandths, their suppliers provide all their engineering information primarily in English units, and parts, tools, etc. are much more available (and cheaper) in English units than in Metric. Not to mention that everything they need to hook up to is English, so they can't just switch over.
By comparison, metric units tend to be either too large or too small: A millimeter is huge (39 thousandths), a tenth of a millimeter is still way too big (3.9 thousandths) but a hundredth of a millimeter is overkill at
Most machinists and designers are proficient in both, but it's a pain. From what I've seen, the vast majority of US design engineers prefer to design in english and if the design has to go overseas for fabrication, they'll then convert and let the other guys deal with the horribly odd numbers that result.
With computers to help us, there's no real reason to HAVE to change anymore. Seriously, it's still a hassle to convert, but it's much less trouble now than it used to be. Converting would be very expensive, cause many more NASA-type foul-ups, and offer little or nothing in return. It makes about as much sense for the US to convert to Metric units as it does for the rest of the world to adopt the English language. Sure, it makes things easier, but is it worth the trouble? And the cultural issues ARE similar.
Finally, there's still a very real stigma attached to using the effete and wimpy Metric units in many US industries. I'll never forget the withering look I got a few years back when explaining to an oil tool executive that a gap was "about two millimeters" as he rejoindered, "MILLIMETERS? What the HELL?"
FWIW, I think both systems are wrong and we should base length on "Dublins" (where the Dublin would be defined as the distance between a yard and a meter at which the acceleration due to earth's gravity is exactly 10 Dublins/s^2)! THAT would make life easier for a lot of people, and is easier than changing the second, which after all is perfect at 1/86400 of a day! [grin]
Oh, and we'd have to build houses out of 5.08x10.16's (2x4's) that actually measure a nominal 4.445x8.890 (1.75x3.5)??
"The future's good and the present is nothing to sneeze at." - Roblimo's last
.... these people aren't exactly Rocket Scientists after all..... oh, wait...nevermind....
01101100 01101001 01101110 01110101 01111000 01110010 01110101 01101100 01100101 01110011
This statement is all right and good except that it is a bit naive. Although the US is non-standard by following it's own measurement systems for lenght, volume, and weight, it is not necessarily bad. Ask just about any professional machinist what measurement system (s)he uses and you'll find more often than not that they use the US "Standard" system over the Metric. A machinst friend of mine claimed, "it's more accurate." Now, as someone acquainted with the more complicated mathematics, I understand measurement systems as nothing more than numbers. Accuracy in and of itself does not lie in the system used to express the measurement. Speaking practically, however, it seems that the US has found its niches. Its not surprising either, we've had a couple hundred years to get used to it.
As a scientist, I realize that the US mesurement system is not used in all aspects of life in the US. Step into any chemist's lab and you'll find beakers labled liters and milliliters. You'll find scales labeled Kilograms, grams, and micrograms. Factors of 10 are convenient indeed when it comes to science.
Hey, I'm all for such a conversion, but such a conversion would never be 100%; at least not for quite a few years. Just think about how the less honest business "entrepeneaurs" would take advantage of the mass confusion caused by such a conversion. Gas would be sold in liters instead of gallons, a two or ten cent raise in price per liter may go unnoticed (initially). Everything would be thrown out of context for US residents. Every industry would be impacted. For the price of conversion, the rewards would be ill received.
Yes, it's simple to say that the US should convert to metric, just not so simple to implement.
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