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NASA Will Go Metric On the Moon
An anonymous reader writes "Space.com is reporting that NASA has decided to use the metric system for its new lunar missions. NASA hopes that metrication will allow easier international participation and safer missions. The loss of the Mars Climate Orbiter was blamed on an error converting between English units and metric units. 'When we made the announcement at the meeting, the reps for the other space agencies all gave a little cheer,' said a NASA official."
Now if only American car companies will budge that extra 17/32" and finish going metric rather than forcing me to have 2 sets of tools for one car. Then I can "Compare Prices on Physics and Engineering" here at /.
The metric system is the tool of the devil! My spaceship gets forty rods to the hogshead and that's the way I likes it!
A metric moon? Not if this president has anything to say about it!
The loss of the Mars Climate Orbiter was blamed on an error converting between English units and metric units.
And to think when we were learning the metric system in school, the teacher told us it didn't take a rocket scientist to figure it out.
I guess he was wrong.
The theory of relativity doesn't work right in Arkansas.
I was under the impression that most scientific agencies used metric as a standard (Guess US educational system failed me there). My father is a builder and I grew up seeing how contractors can be so loose with measurements. It amazes me that NASA got this far using a very inaccurate system (at times) for such precise operations.
Metric is a very easy system to deal with and has been adopted over a large portion of the world. Technically Canada has been metric for over 20 years. Tho things like construction has remained Imperial as we are next to the US. If not for the Us Canada would be completely metric, but since the Us is right next door, we end up in the metric camp with one foot still over in the Imperial side o things. But I don't see the Us converting to metric any time soon, but the scientific community moving to metric to do its work instead of continually converting would be a great leap in the right direction.
when the first McD's is built on the moon, I have to order a "Royal With Cheese" ?
I used to be with IT..now IT seems strange and scary to me.
... is that in the UK we've been using the metric system for at least 20 years!
...they're going right through it?
I have a bad feeling about this. Has this whole metric thing been thoroughly tested?
DecafJedi
my weblog: apropos of something
I'm confused - are they only going to use the Metric system on the Moon?
or is it more like: "Dude, did you see that?! NASA totally went Metric on the Moon's ass!"
Insisting on "correct" English is like saying that there is only one, definitive recipe for chili.
I imagine this will assist the U.S. is its conversion to the metric system, something it has been trying to do for many years now.
Yeah, they started with the 2-liter bottles of soda about 20 years ago, so it looks like they're working their way down the list.
I wonder what comes next, after beverage containers, and interplanetary spacecraft.
The theory of relativity doesn't work right in Arkansas.
.. but when is the rest of the USA going to follow suit?
According to wikipedia, As of 2005 only three countries, the United States, Liberia, and Myanmar (Burma) have not converted to metric yet. Canada officially converted in 1970, but both systems get used on a day-to-day basis. Most tape measures, rulers, etc have both systems. Most older people still use imperial for most things, and younger generations seem to be mixed.
It's actually interesting that a lot of people here (Canada) use mixed units. Personally, I usually use feet if I'm estimating a distance (it's just a very convienient size - the closest metric equivalent is a decimeter, just doesn't quite cut it), and pounds and feet/inches for human weight/height. We still order a pound of wings and a pint of beer (I think you get beat up if you ask for 568mL of beer in a bar). Most other things are metric: road signs are km/h, the weather report is in celcius. Most stores sell things by the kilogram, meter, or liter/milliliter. I'm not sure what they teach kids in school now, but my generation (mid 20's) seems to be decently fluent in both systems (I remember learning how to add inches as part of learning fractions).
Speak before you think
Welcome to the 18th century!
This is a necessary, but difficult transition. Yes, difficult. Maybe it's pretty easy for the programmers, but for the mechanical guys out there (like myself), this introduces a huge relearning phase. Say, for example, I need some sheet metal to function as a structural piece. I can be pretty confident that my initial guess will be pretty close to the final thickness value if specified in imperial units. I also know what's typically readily available from suppliers (eg: 1/4" is far more common than 15/64"). Not only must I do a conversion from my ingrained inch units into "foreign" metric, but I must also look up which sizes are common.
With time, I would be just as good with metric as with imperial units. And I want to change to metric for its obvious advantages. It's just that my design confidence and productivity would falter through the transition. I'm quite sure I'm not alone on this.
IWARS.
People, in general, disappoint me. Politicians even more so.
I should preface this post with the fact that I'm in the US. When I took physics and chemistry in college we barely discussed English units. There was one class period that we talked a little about conversion from English to metric units (I don't believe we even did the opposite), and that was about it. It was just assumed that we knew metric very well already. If I graduated and went to work for NASA and had to use English measures, I think I would have to almost relearn some of the physics--it would be awkward for me to work with the non-SI units, and even more awkward to have to learn new constants (I learned the constants in metric units). So I assumed that NASA had moved away from English units long ago since it hasn't been taught in so long.
These NASA rebels must be stopped. The moon was claimed in the name of the United States by Neal Armstrong, we can't allow them to fruit it up by going all metric on its ass the next time they land there. We should nuke all of NASA's bases from orbit. Some one see about coordinating that with our national space agency.
It secretly amuses me when Americans (one of only three backwards countries that haven't converted) argue about keeping the "imperial" system. All of your current units of measurement have been defined relative to the metric system for the past 50 years or so. From the wiki: "One inch international measure is exactly 25.4 millimeters, while one inch U.S. survey measure is defined so that 39.37 inches is exactly 1 meter". "The pound avoirdupois, which forms the basis of the U.S. customary system of mass, is defined as exactly 453.59237 grams".
When our name is on the back of your car, we're behind you all the way!
Somehow I doubt that the first moon landing teams felt that metric was important. Obviously, they made it (and back). Instead of trying to figure out ways to make things less divisible by three, they should focus on the actual logistics of getting there and back safely.
Of course, the most of the Slashdot crowd think that the metric system is some sort of gift from God. All I know is the bar where I order pints serves them at a proper temperature and you get a little more than the rated 20 UK fluid ounces. Should they switch to the metric system? Will that improve the beer? Will it make the Thames Welsh Bitter taste better? How about Coniston's, or Fuller's, or Paulaner Salvator?
All of my tractors parts are standard measurements. Will changing them to metric make the tractor last longer than the 40 years it already has? Of course, this will be unpopular here, but who cares what other space agencies think? Are they as successful as NASA? Have they broken more new ground? Do they care what we think about their use of the metric system, despite it's weaknesses? Don't think so.
The brains of a chicken, coupled with the claws of two eagles, may well hatch the eggs of our destruction.
Exhibit #1 for why Wikipedia is not to be trusted - they continue to tell half the story. (On this and many other topics, they prefer the simple and popular explanation over completeness and accuracy. [1])
MCO was lost not because of a metric conversion error - but because an increasing divergence between the planned and actual performance was ignored. The official report mentions this - but glosses over its importance. MCO was lost because NASA attempted to fly the mission on the cheap, because of this testing and analysis during the cruise phase was cut from the budget. Some analysis was done on the side by a few engineers - and their calls for a formal analysis went unheeded until too late.
[1] And before the Wikipedia cheerleaders chime in, yes - I have tried to fix many articles to correct this problem. Without exception the corrections were either reverted out or edited into meaninglessness. On Wikipedia the win goes to the editor with time on his hands or who can cite a lightweight popular article as the source of his 'facts'.
It was actually mandated back in 1975 that the US needs to convert to the metric system, check out http://www.pueblo.gsa.gov/cic_text/misc/usmetric/m etric.htm
Quote:
Congress passed the Metric Conversion Act of 1975 "to coordinate and plan the increasing use of the metric system in the United States."
but it all fell apart since there where no deadline and all based onm voluntary conversion.
Rocket nerds in the audiance will probably be familiar with the "Estes Alpha," a simple beginner's kit.
.8 pounds. After the change to metric, these became A5-4 and B4-2 motors, with average thrust given in newtons.
There have actually been many versions, with and without plastic nose cone and fins. No die-hard collectors' set is complete without a "metric" Alpha, briefly produced in the 70s for educational purposes.
Now the instructions have both English and metric measurements . . . where measuring is required at all.
* * *
One model rocket measurement has been metric for going on four decades; the average thrust and total impulse figures for motors. Before 1968 or so, you'd save your paper route money for "A.8-4" or "B.8-2" motors, with an average thrust of
Mmmmm, newtons.
From Wikipedia:
p ng
http://en.wikipedia.org/wiki/Image:Metric_system.
It would be embarassing to have the mission fail simply because of a failure to convert between an assload and a metric assload.
Note that you don't see any movements to "bring back the imperial system" elswhere in the world, because metric *works*.
I run: Windows, OS X, Linux, FreeBSD. Just because you have a hammer, doesn't mean everything is a nail.
President Reagan, in an effort to show he was cutting taxe(which he actually raised) cut the funding to convert everything to metric.
There was a time when American cars had both Metric and english and some roads had metric and english signs(very few). we would be done with the conversion 10 years ago.
More reagan legacy.
The Kruger Dunning explains most post on
Exactly why I propose we just split the difference.
:)
1 yard = 100 Centiyards = 1000 Miliyards
1 pound = 1000 milipounds
you get the idea
you should hear my ideas on how we should change currency
"Personal ownership is a hallmark of conservative capitalism. And I don't believe I am entitled to anything that I did n
But the Death Star would almost certainly use Imperial units, would it not?
If you don't know where you are going, you will wind up somewhere else.
The bigger irony is that they're not even proper "english" units! The fl. oz. is slightly bigger, there are fewer fl. oz. in a pint, the ton is lighter, and have you ever heard Americans measuring their weight in stones? Perhaps they were looking for somebody else to blame for the twisted unit system, and chose the name of the country they rejected in 18th century!
But if they were only going to do it half-assed (0.196850394-assed for metric folks),
I've always heard people talking about "a metric buttload" or "a metric assload" of this, that or the other thing. I never knew how much they were talking about, and I've been too embarassed to ask. Thank you for clearing up the conversion factor between a metric and imperial ass load!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
The fact that the US is non-metric means significantly increased costs for businesses and a barrier to trade. Considering the push in the US to globalise trade (and the realities of a global economy) it makes the most sense from an economic perspective to have the whole world on a single standard - and the rest of the world (as well as the scientific community) has clearly voted on what the standard should be. Furthermore, NASA's foibles show the obvious downside and potential expense of holding on to an outdated system.
Metric is good for all the obvious reasons -- SI units haver fewer weird things going on, conversions are easier, interoperable tools and fittings, etc etc. For all things like discussing distances, velocities, thrust levels, trajectory simulations, and more, I'm completely in favor of metric everywhere.
The one place I don't like this is when it comes to fittings, fasteners, plumbing, etc. Partly it's that metric nuts, bolts, and fittings are harder to find. You can't buy metric pipe fittings around here. Sure, you can order them, but that takes longer and costs more. The cost isn't a big issue on most things, but turnaround time is -- if you find a problem, it's really nice to be able to order a different part and have it the next day, rather than waiting a few days for something from Europe to clear customs and arrive. On some things, though, it actually makes a big difference. A lot of things like large pressure regulators, specialty valves, and more are even harder to find with metric fittings on them -- specifically, they become custom parts, with associated cost increases and weeks of lead time, which is frequently unacceptable.
And before anyone says you can buy metric parts in the US -- sure, you can, as long as they're "normal." It's the specialty parts that are hard. For example, McMaster-Carr stocks 3798 different socket cap screws in English sizes, but only 1610 in metric. If you need a weird metric screw, you may very well be out of luck.
The other major thing is subcontracts -- if I hire a consultant or send a part out to be machined, the machinist needs to have metric tools. Again, most machinists have a basic set of metric tools, but not an entire shop's worth. If the consultant or machinist has to start buying new tooling, your costs and the delivery time start going up.
I'll say it again -- having to buy parts from out of the country is not just a minor nuisance; it has a direct impact on how quickly you can revise a design and do the next test, which directly translates into how long it takes to complete the project.
I'm in favor of working toward compatibility, but it's not nearly as obvious an answer as it looks when it comes to tooling, since the installed base of English tooling and suppliers is *so* *huge* while metric is really only supported because of a few foreign-made parts.
You know its time to change to the metric system when you can read definitions on imperial units from wikipedia like this:
"Because the furlong was "one plough's furrow long" and a furrow was the length a plough team was to be driven without resting, the length of the furlong and the acre vary regionally, nominally due to differing soil types. In England the acre was 4,840 square yards, but in Scotland it was 6,150 square yards and in Ireland 7,840 square yards."
If we keep the imperial system i guess its important to ask what kind of soil the distance is supposed to be? Is it English soil when traveling to the moon? Is the ox well fed? Is it an experienced plough team leading the expedition? Maybe its raining that day and the soil becomes softer?
Come to think of it why should we ever abandon the imperial system!?!
This is a viral signature. You are now infected!
My space probes get forty rods to the hogshead, and that's the way I likes it!!!
I come from Canada and we have yet to fully convert to the metric system; the Mulroney government decided that funding the metric conversion initiative begun by the previous Liberal government was a waste of money and they stopped pushing the issue... but I digress.
Apparently the attempted conversion was disliked by a number of people. My favorite story was about the some of the old people. Somehow they got it into their heads that gasoline sold by the litre was inferior, quality wise, that if the same gasoline was sold by the (imperial) gallon. Yes, these poor individuals went around the country cautioning the masses against putting this 'litre of gasoline' in their cars!
Yeah, right, so that would make it 1000 days in a year? And PI==10.0, I guess. The problem with imperial unit apologists is that they make such unreasonable arguments to try to justify an unreasonable system.
Now, let's get this straight, write it down carefully: the International System unit of time is the second. Minutes, hours, days, weeks, and months are ***NOT*** metric units
We have such weird units of time partly because neither the lunar month nor the solar day are exact divisors of the year and partly because of an old tradition on dividing the day. But, no matter how hours and minutes are counted, these are not part of the International System. You may buy eggs and beer cans by the dozen, but a kilogram is still a thousand grams.
(mind your yoda speech, please)
Actually, it's pretty simple. In NASA units, to convert one inch to centimeters, multiply by $254 million.
I've grown up using Metric, since New Zealand's been standardised on it since well before I was born. I use it all the time, and I love it. So many different units of measurement go between each other in logical ways, many of which aren't noticed by most, right down to things like standard pencil widths being designed to match standard paper sizes. There are definitely problems with using it for day-to-day use, though, which I think most people just put up with. (The metre is often too big, the centimetre isn't big enough, and so on. Blocks of 10 cm would make a lot of sense, and I'm a bit surprised they don't get used.)
What imperial really has going for it, though, and one of the reasons it's so convenient, is that the units make it easier to divide things up for day-to-day tasks. In metric, it's easy to divide by 10, and often by 5 and 2, but outside of that the decimal places start getting long and often end up recurring. Dividing things into threes, fours and sixes really doesn't work if you also want twos and fives.
This is more to do with base 10 than with metric. I've often wondered if metric would be better long term if everyone counted in base 12, instead, and if the relationships between metric units were based on multiples of 12 instead of 10. For day to day use, simpler fractions translate to decimals (or whatever decimals are called in base 12) more nicely with base 12 than base 10. eg.
1/1 in base 10 is 1.0, in base 12 is 1.0.
1/2 in base 10 is 0.5, in base 12 is 0.6.
1/3 in base 10 is 0.333333..., in base 12 is 0.4.
1/4 in base 10 is 0.25, in base 12 is 0.3.
1/5 in base 10 is 0.2, in base 12 is 0.24.
1/6 in base 10 is 0.166666.... in base 12 is 0.2.
Base 12 makes the first 6 fractions easy to write as a decimal, whereas base 10 becomes a real problem. This probably wouldn't be practical because it's a huge learning curve for everyone, but it'd be quite interesting all the same.
You do realize, of course, that using metric units in no way stops you from using fractions rather than decimal whenever it is convenient?
You may use 3/4 cups of something; I'll use 1 1/2 dl. And one pint is a fairly good size for a beer, but then, so is 40cl, the normal size in Sweden. But of course we don't call it "40cl"; it's a "large beer".
If I estimate people's height, I'll just estimate to the nearest 5cm. That is a pretty convenient scale; fine enough to get close, and rough enough for me to have a good chance of being right.
Pretty much none of your arguments have anything to do with the units used, but with how you use them - and you can do it equally with either measurement system. As a guess, you have not had to use metric very much so you just have never built up a collection of mental tools equal to the one's you use for inches and stuff, and so you see it as clumsy and ill-fitting.
Trust the Computer. The Computer is your friend.
No one has actually answered this legitimate question.
"PC LOAD LETTER" ==> (P)rint (C)artridge, (Load Letter) Sized Paper now!"
"PC LOAD LETTER" ==> (P)rint (C)artridge, (Load Letter) Sized Paper now!"
"PC LOAD LETTER" ==> (P)rint (C)artridge, (Load Letter) Sized Paper now!"
"PC LOAD LETTER" ==> (P)rint (C)artridge, (Load Letter) Sized Paper now!"
"PC LOAD LETTER" ==> (P)rint (C)artridge, (Load Letter) Sized Paper now!"
There's only 14 characters on the display, what should it say? "Put In Paper?" Where? The obvious place, of course. Stupid wording, but once you know what it means, it's obvious.
I RTFM.
Unitarian Church: Freethinkers Congregate!
Which is one sixth of 10.
So that would make you, what, a community college drop out?
In pints.
Note however that these are not pints as you know them. Not the pitiful 473ml servings that pass for pints in the colonies. Oh no. One proper pint is 568ml.
This may be why we've never quite gone for the metric system here. We'd end up being served beer in 500ml glasses and that simply won't do. That extra 68ml is important, even if in most pubs it just accounts for the head...
Real Daleks don't climb stairs - they level the building.
Dude, your Imperial system goes to 11 ! Our decimal system only goes up to 10 :(
Q: So how are you going to implement this change to the metric system?
NASA: We will do it inch by inch.
Life is wet, then you dry.
I wish Americans would stop calling them "English" units. Not only are they no longer generally used in England (with the odd exception like pints of beer and miles) but the even when they were used they were different from the American system. For example there are 20 fluid ounces in an Imperial pint vs. 16 fluid ounces in a US pint....so it is a very good thing than NASA is no longer using them for international missions since there isn't even an Imperial standard that anyone can agree on!
"Err...Houston we may have a problem, when you told us to burn 10 pints of fuel was that Imperial pints or US pints?"
I am studying at a reknowned European university who, bizarrely, have the default paper size on their printers set to "US Letter". This means that we can't just print stuff. Every time (Yes, EVERY time) you want to print something you have to go into the print menu and page setup options and change it to A4.
EVERYGODAMNEDFREAKINTIME!!!!!!!
Not that I'm bitter about it.
Travelling forward in time at a rate of 1 second per second.
"You do realize, of course, that using metric units in no way stops you from using fractions rather than decimal whenever it is convenient?"
Actually, it does because ten has less factors (1,2,5,10) than twelve (1,2,3,4,6,12) or sixteen (1,2,4,8,16).
Huh? What stops you from counting in whatever fractions you're comfortable with? If you want to use 4 3/12 deciliters or something, just go ahead.
If I take a stick that's 1 foot long and cut it into four pieces, I have four sticks that are 3 inches long. If I take a stick that's one meter long and cut it into four pieces, I have four sticks that are 25 centimeters long.
You have four stick of 1/4 meter each. If you take one meter and cut into five pieces you get five sticks of 2dm. What does cutting a one foot stick in five pieces get you?
I think you need to calm down a bit; you're sounding quite obsessive about this, to the point of being irrational.
Trust the Computer. The Computer is your friend.
However, a pound of feathers weighs more than a pound of gold, because feathers are measured using the avoirdupois system (1 pound = about 453.59 g) while gold uses Troy (1 pound = about 373.24 g).
Hold on a minute--I always thought that a pound was a pound was a pound, and that a "Troy ounce" was different from a "normal ounce" (1/12 of a pound vs 1/16 of a pound). Now, becaus of you and Wikipaedia I now know that not only are the ounces different AND the number of ounces in each pound are Different, but the size of each pound is different too!
Even more perverse--a Troy Oz is HEAVIER than a normal ox, but a Troy pound is LIGHTER than a normal pound!
It's no wonder y'all down there in the US crash your space probes into planets.
If I had mod points, I'd mod you up. This is something I've been trying to tell people for a LONG time (every time I have this discussion - be it on slashdot or elsewhere)... just because we use metric, it doesn't mean we can't use fractions! A "half metre" makes perfect sense... and most people in Europe are more than familiar with buying half-litres of beer (although that said, it sounds you do something different in Sweden! 40cL, I'm not familiar with - generally 30cL or a half-litre (50cL) when I'm in Europe)
As a note, I do the same thing with height - estimate to the nearest 5cm.
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