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NASA Will Go Metric On the Moon

Posted by kdawson on from the late-conversion dept.

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."

19 of 695 comments (clear)

  1. Yay!!! by Spritzer · · Score: 5, Insightful

    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 /.

    1. Re:Yay!!! by pilgrim23 · · Score: 5, Informative

      as I recall, the fittings on the Apollo 13 launch were metric, the Comamnd Module English. Some fittings were square, others round.... If I was on the moon I would hate to need to change my O2 bottle and in an emergency, the one from contractor B has a English nozzle fitting. Consisitency is not just a good idea here....

      --
      - Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.
    2. Re:Yay!!! by el_womble · · Score: 5, Funny

      I'm British, so I deal with both systems on a daily basis and I think we've got it pretty sorted. Doing something important, where you need accuracy do it in metric doing something fun, do it in imperial.

      Distance to the shops in miles, distance to the sun in kilometers
      I measure my weight in stones and pounds, but I cook in grams.
      Size of my wang in feet (ok, ok inches) size of my windows in cm.

      I'm not sure why Americans feel the need to stick to imperial, especially in light of computers. At least NASA has now seen the light.

      --
      Scared of flying, pointy things snce 1979!
    3. Re:Yay!!! by bgarcia · · Score: 5, Funny
      Both of my "American cars" were actually made in Canada, and are already metric.

      I think the only car companies still making cars in America are the Japanese. :-D

      --
      I'm a leaf on the wind. Watch how I soar.
    4. Re:Yay!!! by Simon+Garlick · · Score: 5, Funny

      I mess around with electric guitars in my nonexistent spare time. Last time I ordered a guitar neck from a US manufacturer it was described as being 43 millimetres wide and 0.85 inches thick, with tuning-machine holes pre-drilled at 11/32 inches.

      --

      -----
      PGP Key ID 0xCB8FF658
    5. Re:Yay!!! by bckrispi · · Score: 5, Funny

      Just like we buy meat by the pound, but cocaine by the kilo!

      --
      Xenon, where's my money? -Borno
  2. Wait a minute..... by lbmouse · · Score: 5, Funny

    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!

  3. and to think by User+956 · · Score: 5, Funny

    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.
  4. Soo.. by dbatkins · · Score: 5, Funny

    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.
  5. "NASA Will Go Metric On The Moon"? by TheWoozle · · Score: 5, Funny

    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.
  6. they've got a list, and they're working on it by User+956 · · Score: 5, Funny

    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.
  7. Good start by gregmac · · Score: 5, Informative

    .. 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
    1. Re:Good start by Freultwah · · Score: 5, Interesting

      I'm European and I've never been exposed to the imperial system. I am thus not tempted to use my hands or feet for measuring anything but the runway length for my long jumps. I've heard of no-one that uses decimetres for measuring distance, either. It's pretty much "metre twenty" or "two forty" everything. The pound thing, I think, would be "half a kilo", the beer issue is solved by asking "a beer". Or "a small beer" for a 0.33 l glass. (Other beer countries' customs and glass sizes do vary.) People weigh something like "75 kilos" and are "metre eighty" tall.

      I guess it shows that even if you would think one system is harder or more cumbersome for certain things than the other, people who have had exposure to only one of them tend to come up with a very flexible and convenient way of measuring stuff. I still get dizzy when a translator fails to translate all the measurements to the target culture's system (all right, there are those rare times when it's desirable to have cubic feet and furlongs in literature), but the North Americans don't.

      My favourite (not) is the standard PC case and its measurements. Have a metric ruler handy and go over it. Everything is very much metric. The 3.5 inch floppy? It's not 8.89 cm, it's exactly 9 cm. The 3.5 inch drive bay? Exactly 10 cm wide. The 5 1/4 inch bay? Not 13.335 cm, exactly 15 instead. Etc. Everything metric from the beginning, re-measured and rounded to fit the imperial system (what with the US probably being the biggest target market in the beginning of the PC). The sad thing is, the rest of the world seems to be accepting it unconditionally. It's as if no-one has had a ruler handy for quite some time.

  8. Necessary but difficult by carambola5 · · Score: 5, Insightful

    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.
  9. We must strike now, before it is to late by PingSpike · · Score: 5, Informative

    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.

  10. American metric system by camperdave · · Score: 5, Interesting

    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!
  11. Countries NOT using the metric system by banditski · · Score: 5, Funny

    From Wikipedia:

    http://en.wikipedia.org/wiki/Image:Metric_system.p ng

  12. Re:Obligatory Quote by amliebsch · · Score: 5, Funny
    That's no moon!

    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.
  13. Re:Another pointless "victory" by Anonymous Coward · · Score: 5, Insightful

    Using the metric or imperial system would not matter one bit if all you're measuring is distance or volume. But as soon as you start converting distance into volume (quick question: how many cubic inches in a pint?), or thrust into velocity (quick: you apply a one-pound force to a one-pound object for one second. What's the resulting speed, measured in mph?), or torque into power, or energy into force or power, the beauty of the SI (metric) system really stands out. In the imperial system, the only way to get these calculations right is to insert all sorts of wacky numbers. Which you need to remember with potentially infinite precision.

    Try this beauty: 1 Nm (Newton-meter) equals 1 J (Joule) equals 1 Ws (Watt-second). In the imperial system you'd have to insert all sorts of wacky numbers to go from pount-feet to calories to, strangely enough, Watt-seconds again. (Electricity, even in the US, is always measured in metric.)

    Or more practical: Ever tried to convert the torque that your car engine delivers (measured in pound-feet) at a certain rpm (rounds per minute) to the horsepower (hp) that it delivers? In SI, it's a simple multiplication: Power (measured in W, or more commonly kW) = 2 * pi * torque (measured in Nm) * rotation speed (measured in 1/s). No wacky, imprecise numbers. Just 2 * pi due to the rotation and that's it.

    The SI system and all the calculations you do with them are completely void of wacky numbers, with only a few exceptions:
    - 2 times pi for anything that involves rotation.
    - Natures constants like c (lightspeed), g (gravitational accelleration), e (elementry electric charge) and a few others, about half an A4 page full of them.
    - Natural properties (like density) of materials that you use.

    Since NASA does *a lot* of these calculations (how much force do you need to accelerate/decelerate the lunar lander, what's the effect of gravity?) I can understand why they switch to metric.