Astronomers Fix the Astronomical Unit

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Astronomers Fix the Astronomical Unit

Posted by Soulskill on Friday September 14, 2012 @05:23AM from the and-changed-the-oil dept.

gbrumfiel writes "The Astronomical Unit (AU) is known to most as the distance between the Earth and the Sun. In fact, the official definition was a much more complex mathematical calculation involving angular measurements, hypothetical bodies, and the Sun's mass. That old definition created problems: due to general relativity, the length of the AU changed depending on an observer's position in the solar system. And the mass of the Sun changes over time, so the AU was changing as well. At the International Astronomical Union's latest meeting, astronomers unanimously voted on a new simplified definition: exactly 149,597,870,700 meters. Nobody need panic, the earth's distance from the sun remains just as it was, regardless of whether it's in AUs, meters, or smoots."

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As everyone knows... by Frosty+Piss · 2012-09-14 05:24 · Score: -1, Troll

The Astronomical Unit is the distence between Taco's anus and ball sack.
It's a FACT, folks...

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If you want news from today, you have to come back tomorrow.
They should mesure it in miles. by Anonymous Coward · 2012-09-14 05:28 · Score: -1

How many miles is that?
1. Re:They should mesure it in miles. by EGSonikku · 2012-09-14 05:49 · Score: 2
  
  Why should they "mesure" it in miles? Metric is standard.
  But to answer your question:
  92,955,807.3 miles
  
  --
  - "Scientia non habet inimicum nisp ignorantem"
2. Re:They should mesure it in miles. by tom17 · 2012-09-14 05:49 · Score: 1
  
  92,955,807.273
3. Re:They should mesure it in miles. by GodfatherofSoul · 2012-09-14 05:57 · Score: 5, Funny
  
  92,955,807.3 miles
  Your answer is SOO 8 minutes ago...
  
  --
  I swear to God...I swear to God! That is NOT how you treat your human!
4. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 06:06 · Score: 0
  
  Metric is standard
  Which metric? MKS, MTS, CGS? They all are now defined in terms of SI units just as much as miles... just not as nice as a conversion.
5. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 06:18 · Score: 0
  
  'Kilogram' isn't a base unit, and neither is 'centimeter'; if it's metric, it should be MGS -- meter/gram/second. It's not our fault the French picked a mass unit that was orders of magnitude out of scale with the dimension unit they picked. Or there's always the FDJ scale -- fermi/dalton/jiffy -- for all the people working with subatomic particles...
6. Re:They should mesure it in miles. by Gilmoure · 2012-09-14 06:22 · Score: 1
  
  * Golf Clap *
  
  --
  I drank what? -- Socrates
7. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 06:30 · Score: 0
  
  'Kilogram' isn't a base unit, and neither is 'centimeter'; if it's metric, it should be MGS -- meter/gram/second. It's not our fault the French picked a mass unit that was orders of magnitude out of scale with the dimension unit they picked. Or there's always the FDJ scale -- fermi/dalton/jiffy -- for all the people working with subatomic particles...
  How can mass units be "orders of magnitude out of scale" with dimensional units?
  That's not even an apples-to-oranges comparison - at least those would both be fruits. Comparing mass and distance is literally nonsensical. What? Are you 3 kg away from me?
8. Re:They should mesure it in miles. by moj0joj0 · 2012-09-14 06:31 · Score: 1
  
  Here, just for you :)
9. Re:They should mesure it in miles. by homey+of+my+owney · 2012-09-14 06:45 · Score: 1
  
  Cool, what is it in furlongs per fortnight?
10. Re:They should mesure it in miles. by SolitaryMan · 2012-09-14 06:52 · Score: 1
  
  You haven't heard of Metric prefixes?
  Those *are* SI units with standard prefixes.
  
  --
  May Peace Prevail On Earth
11. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 06:52 · Score: 0
  
  e.g. a meter long rod/stick with diameter that fits in an average hand grip weighs ~1kg (within an order of magnitude). It's a more "human-sized", for lack of a better term, unit.
12. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 06:55 · Score: 0
  
  Don't mix speed and distance.
13. Re:They should mesure it in miles. by squidflakes · 2012-09-14 07:06 · Score: 1
  
  Miles? Pffft, I want to know the distance in smoots!
14. Re:They should mesure it in miles. by squidflakes · 2012-09-14 07:07 · Score: 1
  
  If you're talking about gravitic attraction between two bodies, you *could* be 3 kg of attraction away from something.
15. Re:They should mesure it in miles. by smoothnorman · 2012-09-14 07:17 · Score: 1
  
  >units '1 au' smoot * 8.7905671e+10 / 1.137583e-11
  
  ...yet perhaps good ol' "units" has yet to update to this shiny new definition of an AU.
16. Re:They should mesure it in miles. by Artifakt · 2012-09-14 07:30 · Score: 1
  
  Most material objects we want to measure fall into a range where a meter long bit of one, or a cubic meter of one, is very unlikely to have a mass expressed in mere grams. For every person who measures, say, the mass of water in a cubic meter of cloud, or something else where the answer is on the order of grams or tens of grams, there are probably about 10,000 measurements and calculations being made where the answer is likely to be in the multiple Kg. range.
  Plus, when the French developed the metric system, a whole lot of the exceptions were totally unknown to them. Modern scientists may be calculating the mass of a cubic meter of dwarf star matter, or how many atoms are in a cubic meter of interstellar space, but the inventors of the metric system probably had no idea at all that the system would need to be extended to such purposes. They did know the system was supposed to be useful for such common calculations as designing a modern sewer system, figuring out how many truckloads of dirt needed to be hauled away from a construction site by both the maximum volume and maximum load weight per truck, or inventorying a bin of bolts by sample methods, and other such commonplace tasks.
  The very fact that so many people use the abreviation mks, or that both of us recognize it easily, says that the fundamental units, before prefixes, are poorly chosen for compatability. If the base units came up frequently together in measurement and calculation,.people would have stuck to using those base units together in the common name, and mks would sound odd.
  
  --
  Who is John Cabal?
17. Re:They should mesure it in miles. by Zinho · 2012-09-14 07:37 · Score: 4, Interesting
  
  How can mass units be "orders of magnitude out of scale" with dimensional units?
  That's not even an apples-to-oranges comparison - at least those would both be fruits. Comparing mass and distance is literally nonsensical. What? Are you 3 kg away from me?
  Mass relates directly to distance, since 1 liter of water (volume of a cube 0.1m on each side) is approximately a kilogram. Alternately, 1 gram is approximately the mass of a cube of water 0.01m on each side; this was, in fact, the original definition as decreed by the French government.
  If the French had chosen the mass of 1m^3 of water as the standard then the unit of mass would be in-scale with the units of distance and volume. In a system like that I could estimate my volume by simply stepping on a scale and reading my mass; the same number would be both my mass and volume, just change the unit label. Instead they chose a system where the volume of the definitive unit mass was 6 orders of magnitude away from the unit volume. As if to confuse matters more, the standard volume unit (liter) is 10^3 smaller than the cube of the unit length and (if holding water) has 10^3 larger mass than the unit mass.
  If you don't care about this, that's fine; neither did the French. They cared more about the units being useful on their own in day-to-day life, and were happy that there was an even factor of 10 difference between the scales. The historical fact remains, though, that the French knowingly chose not to unify their units when creating the system, presenting modern geeks with the first-world problem of needing a conversion factor between mass and volume rather than the units being strictly 1-to-1, and affording them the opportunity to complain about it. Just because the complaint is pointless doesn't make it wrong ;^)
  
  --
  "Space Exploration is not endless circles in low earth orbit." -Buzz Aldrin
18. Re:They should mesure it in miles. by RabidReindeer · 2012-09-14 07:38 · Score: 3, Funny
  
  Don't mix speed and distance.
  Hey, I can do the Kessel Run in 17 parsecs!
19. Re:They should mesure it in miles. by ChrisSlicks · 2012-09-14 07:46 · Score: 1
  
  Google does the conversion if you ask, but it's definition of AU is rounded off. Google "1 au in smoots".
20. Re:They should mesure it in miles. by aeortiz · 2012-09-14 07:54 · Score: 1
  
  I thought the plural of Smoot was Smeet!
21. Re:They should mesure it in miles. by KhabaLox · 2012-09-14 08:22 · Score: 1
  
  92,955,807.3 miles
  "And that's why it looks so small."
  
  --
  Ceci n'est pas un sig.
22. Re:They should mesure it in miles. by Zinho · 2012-09-14 08:22 · Score: 1
  
  You haven't heard of Metric prefixes?
  Those *are* SI units with standard prefixes.
  Of course he has. And the gram is not the SI mass unit, the kilogram is:
  
  Despite the prefix "kilo-", the kilogram is the base unit of mass, the kilogram, not the gram, is used in the definitions of derived units.
  Nonetheless, units of mass are named as if the gram were the base unit.
  Neither the MKS nor the CGS metric system variant is consistent in this way; one uses a "kilo" prefix on the base mass unit, the other uses the "centi" prefix for its unit length. The AC you're responding to would probably be happier using the MTS variant.
  His complaint may be of a first-world problem, but he's not wrong.
  
  --
  "Space Exploration is not endless circles in low earth orbit." -Buzz Aldrin
23. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-14 08:43 · Score: 0
  
  Don't mix speed and distance.
  Hey, I can do the Kessel Run in 17 parsecs!
  actually parsecs makes sense if the skill is choosing the shortest route while still making safe jumps.
  (sw is full of stupid shit though)
24. Re:They should mesure it in miles. by History's+Coming+To · 2012-09-14 09:51 · Score: 1
  
  You do realise that fuel efficiency in cars is measured in square metres? Unit cancellation is wierd. Oblig/Ref: according to my graph xkcd will produce a cartoon to answer a /. post in advance within six months.
  
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25. Re:They should mesure it in miles. by yotto · 2012-09-14 11:37 · Score: 1
  
  I know a dude who did it in 12.
  
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  Pulp Audio Weekly - Geek News and Reviews
26. Re:They should mesure it in miles. by denelson83 · 2012-09-14 11:48 · Score: 1
  
  I'm sorry, but I don't know what a mile is. And since my brain is hard-wired to the SI system, it's impossible for me to know.
27. Re:They should mesure it in miles. by Tastecicles · 2012-09-14 13:10 · Score: 1
  
  1602 metres (to use the CORRECT SPELLING).
  
  --
  Operation Guillotine is in effect.
28. Re:They should mesure it in miles. by Tastecicles · 2012-09-14 13:24 · Score: 1
  
  depends what it's made of (foam rubber or neutronium?) and where you are measuring it (an object weighs 2.36x more on Jupiter than it does on Earth. The same object weighs 27x more on the Sun than it would on Earth. Its mass would be the same).
  The SI unit of weight is the Newton. This is defined as the contact reaction-force against the force of gravity, for an object at rest on the ground. For a solid object with a mass of 1 kilogram, weight is equal to 9.80665 Newtons.
  Incidentally, the outward force (centripetal acceleration) imparted by the spin of the Earth means that the weight of an object at rest is slightly less at the Equator than it is at either Pole. Such observation is proved by the slight equatorial bulge of the Earth caused by the same outward force.
  
  --
  Operation Guillotine is in effect.
29. Re:They should mesure it in miles. by Tastecicles · 2012-09-14 13:28 · Score: 1
  
  are we talking about a cloud of condensed water vapour, a cloud of droplets, or a cloud of steam?
  For the last, that's easy: any gas at ground level and standard temperature and pressure has a density of 1 mol per 27 cubic metres. For monatomic oxygen, that's approximately 16 grams of gas in a fairly large room.
  For the others, pick a number out of your arse, that's probably as good a guess as you're gonna get.
  
  --
  Operation Guillotine is in effect.
30. Re:They should mesure it in miles. by Tastecicles · 2012-09-14 14:24 · Score: 1
  
  I just read the wiki entry on the Smoot, made me chuckle. Amazing how a college prank can live on such as it has.
  
  --
  Operation Guillotine is in effect.
31. Re:They should mesure it in miles. by pablo.cl · 2012-09-14 15:11 · Score: 1
  
  an object weighs 2.36x more on Jupiter than it does on Earth. The same object weighs 27x more on the Sun than it would on Earth. Its mass would be the same
  I assume you'll be surprised that for many people, weigh means: to hold up or balance, as in the hand, in order to estimate the amount of mass;
32. Re:They should mesure it in miles. by Guignol · 2012-09-14 21:18 · Score: 1
  
  Or on a wii-fit challenge :)
33. Re:They should mesure it in miles. by RabidReindeer · 2012-09-15 00:15 · Score: 1
  
  I know a dude who did it in 12.
  Don't believe him. He's just messing with your head.
34. Re:They should mesure it in miles. by Anonymous Coward · 2012-09-15 00:19 · Score: 0
  
  WRONG.
  mass doesn't directly relate to distance. Mass relates to density * distance.
  If I just choose a substance with a different density than water, I can come up with something that will have a mass of 1 kg for a volume of 1m^3.
  For example I could take 1 kg of any gas, compress it into 1m^3, and voila, no more difference between unit of volume and unit of mass.
  Your argument is retarded.
35. Re:They should mesure it in miles. by gomiam · 2012-09-15 09:23 · Score: 1
  
  You are right, mass relates to density by distance. Yet you glossed over the fact (stated in the comment you answer to) that the first definition of gram was water density * distance (cubed). Please read carefully before calling an argument both rational and based on historic facts retarded. It may be useless, it may be pissing against the wind, but isn't retarded.
  By the way your argument about being able to choose any gas and compress it is interesting, but it doesn't even match history. Nobody ever used compressed gas as a reference for mass, AFAIK.
36. Re:They should mesure it in miles. by Murasaki+Skies · 2012-09-15 13:23 · Score: 0
  
  1609.344 meters (to use the CORRECT NUMBER)
  
  --
  Waiiii!!!!!! I have bad karma!
37. Re:They should mesure it in miles. by maxwell+demon · 2012-09-15 23:55 · Score: 1
  
  Well, when the name invented by a nine-year old child for a certain large number can end up, slightly modified, as the name of one of the major companies of the internet which everyone has heard about, then a college prank living on on some Wikipedia page and as a feature in a calculator which incorporates a lot of jokes (ever wanted to know what 2^(the answer to life, the universe and everything) is? Just ask Google!) doesn't look that amazing to me.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
38. Re:They should mesure it in miles. by ChrisSlicks · 2012-09-16 01:56 · Score: 1
  
  Definitely one of the timeless ones (they do need to freshen the paint on the bridge though, it's been fading recently).
  
  I always love visiting the MIT campus, you'll never know what you might find. I try not to gawk at the students, although sometimes they gawk at me since I look like a 40 year old student of MIT.
  
  You can see more hacks in the gallery.
  http://hacks.mit.edu/Hacks/by_year/
39. Re:They should mesure it in miles. by Tastecicles · 2012-09-16 11:12 · Score: 1
  
  touché.
  
  --
  Operation Guillotine is in effect.
let's not waste significant digits! by markhahn · 2012-09-14 05:30 · Score: 4, Funny

you'd think they could have rounded up to 150 gigameters.
if politicians can be SD-conservative, why can't astronomers? we all know that significance is precious and rare...
1. Re:let's not waste significant digits! by girlintraining · 2012-09-14 05:34 · Score: 5, Funny
  
  if politicians can be SD-conservative, why can't astronomers? we all know that significance is precious and rare...
  It was decided by committee. I'm sure it was a compromise of several possible values, with concessions on each side, a few attempts to filibuster it until Pluto was given recognition again, etc. No, I'm not trying to be funny.
  
  --
  #fuckbeta #iamslashdot #dicemustdie
2. Re:let's not waste significant digits! by cp5i6 · 2012-09-14 05:34 · Score: 2
  
  If they're goint o pick an arbitrary number, why even make it so complicated.
  
  they should just say 1 AU = 42 and be done with it.
3. Re:let's not waste significant digits! by SJHillman · 2012-09-14 05:35 · Score: 2
  
  Most of the time, 150 gigameters will probably be close enough, similar as to how 300,000 km/s is "close enough" to the speed of light for many things or 3.1415 is "close enough" to pi for many things.
4. Re:let's not waste significant digits! by FitForTheSun · 2012-09-14 05:45 · Score: 1
  
  The difference is a quarter-million miles. Science is more precise than that when it is able to be.
5. Re:let's not waste significant digits! by Jason+Levine · 2012-09-14 05:48 · Score: 2
  
  Or rounded down to 137,438,953,472 meters - 2^37 meters.
  
  --
  My sci-fi novel, Ghost Thief, is now available from Amazon.com.
6. Re:let's not waste significant digits! by Tobenisstinky · 2012-09-14 05:52 · Score: 2
  
  Yes, but it is 'a quarter-million miles' difference between two arbitrary values. So why not make it a nice round number?
  
  --
  wha'? where am i?
7. Re:let's not waste significant digits! by icebike · 2012-09-14 05:54 · Score: 5, Interesting
  
  you'd think they could have rounded up to 150 gigameters.
  if politicians can be SD-conservative, why can't astronomers? we all know that significance is precious and rare...
  Interesting point.
  If you are going to pic arbitrary number, why not pick an easy one?
  I suspect there is a desire to keep all past references to AU meaningful within a small margin of error, so as to not have to translate any written works.
  The difference between the new arbitrary number and the prior imprecise one is probably infinitesimally small for the scale of reference AUs are use for.
  Rounding it up almost half a million kilometers (quarter million miles) maybe not so much.
  I suspect that since it was imprecise in the first place, and used for almost nothing except astronomical reference, preserving existing references in the literature was more important than the ease of writing it down.
  
  --
  Sig Battery depleted. Reverting to safe mode.
8. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 05:57 · Score: 0
  
  Or we could just re-define meter as AU times 1/150,000,000,000. Or start using a new metric, AU-meters.
9. Re:let's not waste significant digits! by hde226868 · 2012-09-14 06:01 · Score: 5, Informative
  
  This is correct. originally the AU was defined as the average distance between the Earth and the Sun. The problem then was to convert this distance to meters. The way to do this conversion in the end involves the product of the mass of the Sun and the Gravitational constant G. Both quantities are not well known (e.g., G is known to 4 or 5 digits only). But their product can be determined from modeling the motions in the Solar system to much higher precision. So by that time the AU was then redefined by defining the product GM (often called k^2, where k is called the "Gaussian gravitational constant"). It is my understanding that this has now been simplified. The difference between both is only a few meters.
10. Re:let's not waste significant digits! by Antipater · 2012-09-14 06:05 · Score: 1
  
  If you are constantly somewhere between 2.328 and 2.347 feet from me, I'm not going to define the distance between us as 2.000 feet simply because "it's a nice round number."
  
  --
  Everything is better with chainsaws.
11. Re:let's not waste significant digits! by icebike · 2012-09-14 06:08 · Score: 1
  
  Most of the time, 150 gigameters will probably be close enough, similar as to how 300,000 km/s is "close enough" to the speed of light for many things or 3.1415 is "close enough" to pi for many things.
  Well the speed of light can be measured fairly precisely and Pi is available to just about any random number of digits you want.
  You are free to choose the level of precision that fits the problem at hand.
  The distance to the sun, on the other hand, was always imprecise, and constantly changing. It depended on when you measured it.
  Apparently this drift in the AU constant started to matter in some calculations, and perhaps threatened interpretation of historical references and calculations.
  The difference of using 150 gigameters is OVER one light-second (402129 km), so there would have had to be a significant rewriting of historical research and measurements. Not an insurmountable problem, just a messy one.
  
  --
  Sig Battery depleted. Reverting to safe mode.
12. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 06:14 · Score: 0
  
  Blasphemer!
  Pi == 3
13. Re:let's not waste significant digits! by FishOuttaWater · 2012-09-14 06:21 · Score: 2
  
  You'd think we would at least use gm instead of million km. What's with the bizarre preference for km for long distances? (Not just here, but darned near everywhere.)
14. Re:let's not waste significant digits! by atrain728 · 2012-09-14 06:25 · Score: 1
  
  A more appropriate comparison: If you are constantly somewhere between 2.02797643 and 1.96131053 feet from me, I'm not going to give other distances of relative scale, in terms of our distance, as 2.00000000 feet simply because "it's a nice round number."
15. Re:let's not waste significant digits! by jdray · 2012-09-14 06:39 · Score: 2
  
  I'm sure it was a compromise of several possible values, with concessions on each side, a few attempts to filibuster it until Pluto was given recognition again, etc. No, I'm not trying to be funny.
  Well, you succeeded anyway.
  
  --
  The Spoon
  Updated 6/28/2011
16. Re:let's not waste significant digits! by courteaudotbiz · 2012-09-14 06:43 · Score: 1
  
  1 AU = 42
  Has anyone here noticed that? Why, when someone picks a random number, 12 and 42 come out so often? Has there been some research done on that?
17. Re:let's not waste significant digits! by cffrost · 2012-09-14 06:43 · Score: 4, Funny
  
  If you are constantly somewhere between 2.328 and 2.347 feet from me, I'm not going to define the distance between us as 2.000 feet simply because "it's a nice round number."
  Agreed; I'd define that distance as "all up in my grill," and I'd define that trajectory as "cruisin' for a bruisin'."
  
  --
  Thank you, Edward Snowden.
  
  "Arguments from authority are worthless." —Carl Sagan
18. Re:let's not waste significant digits! by Antipater · 2012-09-14 06:45 · Score: 4, Informative
  
  You're missing my point. 150GM wasn't "between" the old measurements. It was just kinda-somewhere-near them.
  
  --
  Everything is better with chainsaws.
19. Re:let's not waste significant digits! by jdray · 2012-09-14 06:45 · Score: 1
  
  We could have just waited until the time was right and the Earth was 150 gigameters from the sun, then declared the value. That is, presuming that the variance in the distance ever achieved 150 GM...
  
  --
  The Spoon
  Updated 6/28/2011
20. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 06:47 · Score: 0
  
  I would question the research of any scientist who willingly used a unit of measurement that, even at the moment of its conception, would have a volatile conversion to solid units.
21. Re:let's not waste significant digits! by Obfuscant · 2012-09-14 06:47 · Score: 1
  
  Has there been some research done on that?
  They looked it up in the Encyclopedia Galactica.
22. Re:let's not waste significant digits! by icebike · 2012-09-14 06:53 · Score: 1
  
  I would question the research of any scientist who willingly used a unit of measurement that, even at the moment of its conception, would have a volatile conversion to solid units.
  So, you relegate the entire field of Astronomy to the fate of Astrology then Mr. AC?
  
  --
  Sig Battery depleted. Reverting to safe mode.
23. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 06:55 · Score: 0
  
  I almost choked on my German salami :D
  On a serious note I think the reason why they didn't rounded it up is the possibility of interstellar travel. At such distances rounding up or down your course by even a 1000 meters will put you miles away from your destination (actually, more like millions upon millions of miles away). So if you want to get back to Earth from Alpha Centauri you just point your compass at the Sun, take precisely 1AU off your course, and voilà - you're roughly on Earth's orbit. Convenient! That's my theory anyway...
24. Re:let's not waste significant digits! by Antipater · 2012-09-14 06:55 · Score: 4, Funny
  
  1 AU = 42
  Has anyone here noticed that? Why, when someone picks a random number, 12 and 42 come out so often? Has there been some research done on that?
  I wouldn't panic about it.
  
  --
  Everything is better with chainsaws.
25. Re:let's not waste significant digits! by Gripp · 2012-09-14 06:56 · Score: 1
  
  42 has geeky significance (http://en.wikipedia.org/wiki/The_Hitchhiker%27s_Guide_to_the_Galaxy#The_Hitchhiker.27s_Guide_to_the_Galaxy). That is why you see it here a lot. as for 12... i dunno.
26. Re:let's not waste significant digits! by SolitaryMan · 2012-09-14 06:57 · Score: 1
  
  There are researches on that. This is the simplest one I can find, you your google-fu to find more.
  
  --
  May Peace Prevail On Earth
27. Re:let's not waste significant digits! by doshell · 2012-09-14 06:58 · Score: 2
  
  Well the speed of light can be measured fairly precisely
  Actually, the speed of light is not the result of a measurement, because the meter is defined in terms of the speed of light. The speed of light, by definition, is always 299,792,458 metres per second.
  
  --
  Score: i, Imaginary
28. Re:let's not waste significant digits! by doshell · 2012-09-14 07:04 · Score: 1
  
  It becomes particularly not-so-funny when you have to constantly make the distinction between American and European billions (as is the case e.g. with money). If everyone agreed on using the giga and tera prefixes, that would never be a problem.
  
  --
  Score: i, Imaginary
29. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 07:07 · Score: 0
  
  Gm
30. Re:let's not waste significant digits! by CreatureComfort · 2012-09-14 07:28 · Score: 1
  
  I'm sure it's 150 gigameters when you use PI=3 in the equations.
  
  --
  "Unheard of means only it's undreamed of yet,
  Impossible means not yet done." ~~ Julia Ecklar
31. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 07:39 · Score: 0
  
  You mean "Western Continental Europe (and former colonies) billions" and "The rest of the world (Minus part of Asia) billions." Unless of course you're kicking the U.K., Greece, and all of Eastern Europe off the continent.
32. Re:let's not waste significant digits! by mhajicek · 2012-09-14 07:40 · Score: 1
  
  However, since the AU is an arbitrary number that only approximates the ever changing distance between the Earth and Sun, one arbitrary number in the proper range would be as good as another.
33. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 07:53 · Score: 0
  
  The difference of using 150 gigameters is OVER one light-second (402129 km), so there would have had to be a significant rewriting of historical research and measurements. Not an insurmountable problem, just a messy one.
  Just ask Russians, They got some experience with rewriting historical data.
34. Re:let's not waste significant digits! by atrain728 · 2012-09-14 09:11 · Score: 1
  
  Aphelion 152,098,232 km
  Perihelion 147,098,290 km
  http://en.wikipedia.org/wiki/Earth
  So yes, I'd say it's between them. Further, the numbers I cited are the exact ratios adjusted for your example.
35. Re:let's not waste significant digits! by Anonymous Coward · 2012-09-14 09:14 · Score: 0
  
  12 is a convenient real world "base" because it is evenly divisible a large number of ways (2,3,4,and 6). Because of that many items are sold in 12 count (1 dozen) packages, making it a familiar number to most people.
  42, is Douglas Adams' answer to the ultimate question of life the universe and everything. It is also 2 dozen, making it familiar to most people.
36. Re:let's not waste significant digits! by Antipater · 2012-09-14 09:36 · Score: 1
  
  http://en.wikipedia.org/wiki/Astronomical_unit#Definition
  As the article stated, the AU hasn't depended directly on the perihelion/aphelion since 1976. The measurements we were working with before today's announcement were 149,597,870,703m and 149,597,870,697m. 150Gm isn't in that range of 6 meters.
  
  --
  Everything is better with chainsaws.
37. Re:let's not waste significant digits! by TapeCutter · 2012-09-14 12:23 · Score: 1
  
  If they rounded it up to 150 million kilometers people would just remember it, much better if people have to look it up and be reminded who defined it. Yes, I'm being cynical.
  
  --
  And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
38. Re:let's not waste significant digits! by Tastecicles · 2012-09-14 13:31 · Score: 1
  
  Screw your decimal, 22/7 is good enough for me.
  
  --
  Operation Guillotine is in effect.
39. Re:let's not waste significant digits! by Tastecicles · 2012-09-14 14:32 · Score: 2
  
  actually, you'd need to offset by 1/1.34" relative to the Solar ecliptic plane. Drift error would likely far exceed that.
  *figure obtained by the distance between Cen AB and Sol (4.37LY) and considering the Parsec as defined: the distance at which a 1AU separation describes 1 second of arc (3.26LY).
  
  --
  Operation Guillotine is in effect.
40. Re:let's not waste significant digits! by danlock4 · 2012-09-14 17:24 · Score: 1
  
  12 is a convenient real world "base" because it is evenly divisible a large number of ways (2,3,4,and 6).
  If you're referring to all positive integers by which 12 is divisible, you can't forget 1. :)
  
  --
  To .sig or not to .sig, that is the question.
41. Re:let's not waste significant digits! by davester666 · 2012-09-15 06:41 · Score: 1
  
  said the man who carries his towel everywhere...
  
  --
  Sleep your way to a whiter smile...date a dentist!
42. Re:let's not waste significant digits! by maxwell+demon · 2012-09-16 00:01 · Score: 1
  
  Well, open Google and type "the answer to life, the universe and everything" in the search bar. Then you'll get the answer to your question (as well as the answer to life, the universe and everything).
  Don't add an exclamation mark, unless you are prepared for big numbers (but not too big; only slightly bigger that the root of the googol). ;-)
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
43. Re:let's not waste significant digits! by maxwell+demon · 2012-09-16 00:04 · Score: 1
  
  12 is a convenient real world "base" because it is evenly divisible a large number of ways (2,3,4,and 6). Because of that many items are sold in 12 count (1 dozen) packages, making it a familiar number to most people.
  42, is Douglas Adams' answer to the ultimate question of life the universe and everything. It is also 2 dozen, making it familiar to most people.
  I think you have that backwards: 2 dozen is 24, because a dozen is 12 (there's it again :-))
  Actually, 42 is three and a half dozen.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
44. Re:let's not waste significant digits! by maxwell+demon · 2012-09-16 00:05 · Score: 1
  
  12 is a convenient real world "base" because it is evenly divisible a large number of ways (2,3,4,and 6).
  If you're referring to all positive integers by which 12 is divisible, you can't forget 1. :)
  And 12 itself.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
No, panic. by girlintraining · 2012-09-14 05:31 · Score: 4, Funny

Nobody need panic, the earth's distance from the sun remains just as it was, regardless of whether it's in AUs, meters, or smoots."
I'm more concerned about the fact that the distance changes depending on where we are. That means that the Earth is moving, and I don't believe in that. It's more heliocentric non-sense by the astronomical community. What next; astronomical bodies that aren't perfectly spherical? The madness of the commoners, I tell you.

--
#fuckbeta #iamslashdot #dicemustdie
1. Re:No, panic. by Antipater · 2012-09-14 05:49 · Score: 1
  
  Relax, would you? The equant lets it all fit back together nicely. Ptolemy's Standard Model still fits the data; there's no need to bring pseudoscience like heliocentricity into this.
  
  --
  Everything is better with chainsaws.
2. Re:No, panic. by Anonymous Coward · 2012-09-14 05:51 · Score: -1
  
  Eppur si muove
3. Re:No, panic. by girlintraining · 2012-09-14 07:20 · Score: 1
  
  Relax, would you? The equant lets it all fit back together nicely. Ptolemy's Standard Model still fits the data; there's no need to bring pseudoscience like heliocentricity into this.
  You are further proof that astronomers have absolutely no sense of humor.
  
  --
  #fuckbeta #iamslashdot #dicemustdie
4. Re:No, panic. by Antipater · 2012-09-14 08:03 · Score: 1
  
  You might want to read my post again. I was playing along with a joke that you yourself had started, so, basically, you just whooshed yourself.
  
  --
  Everything is better with chainsaws.
5. Re:No, panic. by idontgno · 2012-09-14 09:03 · Score: 1
  
  In space you can't hear you "Whoosh".
  
  --
  Welcome to the Panopticon. Used to be a prison, now it's your home.
6. Re:No, panic. by keytoe · 2012-09-14 10:26 · Score: 1
  
  I'm more concerned about the fact that the distance changes depending on where we are. That means that the Earth is moving, and I don't believe in that. It's more heliocentric non-sense by the astronomical community. What next; astronomical bodies that aren't perfectly spherical? The madness of the commoners, I tell you.
  Spheres? Heathen!
  
  --
  Culture is more than commerce
7. Re:No, panic. by girlintraining · 2012-09-14 12:25 · Score: 1
  
  You might want to read my post again. I was playing along with a joke that you yourself had started, so, basically, you just whooshed yourself.
  No, I just played along with your joke of my joke, which apparently resulted in a black hole.
  
  --
  #fuckbeta #iamslashdot #dicemustdie
8. Re:No, panic. by mdielmann · 2012-09-14 18:05 · Score: 1
  
  Nobody need panic, the earth's distance from the sun remains just as it was, regardless of whether it's in AUs, meters, or smoots."
  I'm more concerned about the fact that the distance changes depending on where we are. That means that the Earth is moving, and I don't believe in that. It's more heliocentric non-sense by the astronomical community. What next; astronomical bodies that aren't perfectly spherical? The madness of the commoners, I tell you.
  Clearly, you are an ignoramus, believing that the Earth is the center of the universe. I suppose you think Mercury does that little dance in homage to us, right?
  No, what bothers me isn't the idea that we're moving, but that we're not moving in a spherical path. I literally don't know if we're coming or going!
  
  --
  Sure I'm paranoid, but am I paranoid enough?
Mass of Sun by Anonymous Coward · 2012-09-14 05:32 · Score: 0

What does the mass of the Sun have to do with the distance between the Sun and Earth?
Good grief! I'm having flashbacks to the lectures about units from my physics teacher!
1. Re:Mass of Sun by Dr.+Tom · 2012-09-14 05:35 · Score: 0
  
  Relativity. Large masses bend space. I guess you never heard about that?
2. Re:Mass of Sun by saveferrousoxide · 2012-09-14 05:44 · Score: 1
  
  No need for snarkiness Dr. Your last sentence was wholly unnecessary. For all you know the AC's a 6th grader still learning the ins and outs of Newtonian physics. Or maybe it's someone with a PhD in something you know nothing about.
3. Re:Mass of Sun by Anonymous Coward · 2012-09-14 05:45 · Score: 0
  
  My balls cause gravitational lensing.
4. Re:Mass of Sun by SJHillman · 2012-09-14 05:49 · Score: 2
  
  Dr. Tom's sense of self-importance is bending space around him. Be careful you don't get sucked in. Once you cross the ego's event horizon, not even snarkiness can escape.
5. Re:Mass of Sun by Baloroth · 2012-09-14 05:58 · Score: 1
  
  What does the mass of the Sun have to do with the distance between the Sun and Earth?
  Good grief! I'm having flashbacks to the lectures about units from my physics teacher!
  The more massive a body, the stronger the gravity. The stronger the gravitational field, the closer Earth will end up to the Sun for a given speed (the Earth's speed in this case being more or less a constant. I'm simplifying since the Earth speeds up and slows down as it orbits, but the point is still the same). Likewise, with less mass the Earth will end up farther away.
  Also relativistic effects, but those are (probably) a lot less pronounced.
  
  --
  "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
6. Re:Mass of Sun by Gilmoure · 2012-09-14 06:35 · Score: 1
  
  Forward takes you out, out takes you back, back takes you in, in takes you forward.
  
  --
  I drank what? -- Socrates
7. Re:Mass of Sun by AJWM · 2012-09-14 14:11 · Score: 1
  
  Always nice to see another Niven fan.
  
  --
  -- Alastair
8. Re:Mass of Sun by maxwell+demon · 2012-09-16 00:11 · Score: 1
  
  My balls cause gravitational lensing.
  That's because they are black holes: Nothing ever leaves them.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
9. Re:Mass of Sun by davewoods · 2012-09-17 01:09 · Score: 1
  
  Ooooohhhh.... Snap.
10. Re:Mass of Sun by DrVxD · 2012-09-26 10:16 · Score: 1
  
  Kendy for the state...
  
  --
  Not everything that can be measured matters; Not everything that matters can be measured.
Distance remains the same? by wierzpio · 2012-09-14 05:34 · Score: 3, Informative

Since the Earth's orbit around the Sun is eliptical it's _never_ the same, is it?
1. Re:Distance remains the same? by mblase · 2012-09-14 05:37 · Score: 5, Funny
  
  Since the Earth's orbit around the Sun is eliptical it's _never_ the same, is it?
  Even an elliptical orbit is right twice a year.
2. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 05:38 · Score: 0
  
  It is now. This committee just decided Earth's orbit is a perfect circle
3. Re:Distance remains the same? by Marc+Madness · 2012-09-14 05:42 · Score: 1
  
  The Astronomical Unit (AU) is known to most as the mean distance between the Earth and the Sun
  The summary omitted the word "mean". The linked article has the correct description.
4. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 05:44 · Score: 0
  
  Even an elliptical orbit is right twice a year.
  Around here, we call them equinoxes.
5. Re:Distance remains the same? by SJHillman · 2012-09-14 05:45 · Score: 1
  
  Assuming the sun as at the center of the ellipse - which I believe it isn't in this case. So it's right roughly once a year.
6. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 05:47 · Score: 0
  
  Unless min or max is used.
7. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 05:49 · Score: 0
  
  Even an elliptical orbit is right twice a year.
  Around here, we call them equinoxes.
  Equinoxes has to do with the direction the earths poles point in relation to the sun, not the location on the ellipse. I don't want to do the math but with keplers laws i don't think the two points of average distance from the sun would be equally spaced in the year.
8. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 05:55 · Score: 0
  
  I think it's a right angle joke, not a right (mean) distance joke.
9. Re:Distance remains the same? by morningstar8 · 2012-09-14 05:56 · Score: 2
  
  Unless it's a min or a max, it's right four times a year!
10. Re:Distance remains the same? by jstave · 2012-09-14 05:58 · Score: 1
  
  Assuming the sun as at the center of the ellipse - which I believe it isn't in this case. So it's right roughly once a year.
  Actually, depending on how big the ellipse is compared with the circle with a 1 AU radius, it could be right from 0 times (circle way too big, or way too small), to as many as 4. Play around with an ellipse and a circle centered at one focus and you'll see what I mean. As the relative sizes change, the number of times it's right changes too. Thank god we got *that* straightened out.
11. Re:Distance remains the same? by pigiron · 2012-09-14 05:59 · Score: 0
  
  Typical Slashdot sloppiness. But what else can you expect. Slashdot headline writers are a bunch of pig ignorant programmers (at best) not scientists.
12. Re:Distance remains the same? by immaterial · 2012-09-14 06:10 · Score: 2
  
  It couldn't be zero (circle way to big/small) if 1 AU is based on the average distance. But you're right that it could be 4 (or 3!) in addition to 2.
13. Re:Distance remains the same? by Baloroth · 2012-09-14 06:13 · Score: 4, Interesting
  
  The center is actually the center of mass for the Earth-Sun. Actually, I believe it's the center of mass for the whole solar system, but if we treat it as a 2-body problem it's just the Earth-Sun. If only the Earth was affecting the Sun with it's gravity, the distance would be right twice a year (assuming the major or minor axis) or 4 times (if you use some other axis), since the Sun would be traveling in an ellipse identical to the Earth's but proportionately smaller, so it would be on the fall on the axis at the same time as the Earth would every single year.
  In reality the Sun is also moved by the other planets, so the distance will never be correct, since it isn't moving on a pure ellipse at all. Also the Earth isn't either. That's why we use the average distance over a few years, since that will always be the average. Except for the fact that the Sun is losing mass, and therefore gravity, so Earth gets further away every year, so the average is itself changing.
  
  --
  "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
14. Re:Distance remains the same? by canajin56 · 2012-09-14 06:24 · Score: 1
  
  The semi-major axis is usually called the "distance" because it's equal to the averaged mean distance between the planet and the foci (one of which is the sun). Though that depends what you average over. I think if you average over time it's approximately equal if eccentricity is small.
  
  --
  ASCII stupid question, get a stupid ANSI
15. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 07:19 · Score: 0
  
  Thank god we got *that* straightened out.
  No need to thank god for that. God put us on the wrong track by suggesting us the earth was the center of the universe and the sun is orbiting it, and we needed a lot of scientific proof before the writings of god about this were discarded as incorrect.
16. Re:Distance remains the same? by Anonymous Coward · 2012-09-14 09:24 · Score: 0
  
  I foresee that we will need some "leap" correction at irregular intervals to correct for these effects.
17. Re:Distance remains the same? by residieu · 2012-09-14 09:32 · Score: 1
  
  The center of mass of the Earth-Sun is at the focus (1 of 2), not the center of the ellipse.
18. Re:Distance remains the same? by denelson83 · 2012-09-14 11:52 · Score: 1
  
  Yes, but the AU was supposed to have been based off the mean distance between the Earth and the Sun over one orbit of Earth around the Sun.
19. Re:Distance remains the same? by maxwell+demon · 2012-09-16 00:14 · Score: 1
  
  Well, it's a four letter word, therefore they had to edit it out.
  Err ..., it's a letter, therefore had to it out.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
20. Re:Distance remains the same? by davewoods · 2012-09-17 01:20 · Score: 1
  
  The center of mass between two bodies is the Barycenter.
  
  The wikpedia page actually has a sweet diagram of the Barycenter for the solar system over the last 50 years.
  
  (I do not understand most of the words, or any of the math, but I like the pictures!)
The new AU ... by PPH · 2012-09-14 05:38 · Score: 5, Funny

... will be established by machining a bar of pure platinum to a length of exactly 1 AU. It will be stored in a vault in Paris.

--
Have gnu, will travel.
1. Re:The new AU ... by wonkey_monkey · 2012-09-14 05:47 · Score: 3, Funny
  
  But they won't be able to shut the door unless the bar is moving at relativistic speeds.
  
  --
  systemd is Roko's Basilisk.
2. Re:The new AU ... by jmv · 2012-09-14 05:47 · Score: 4, Funny
  
  Apparently they decided to define it by sticking a large rock in orbit around the sun.
  
  --
  Opus: the Swiss army knife of audio codec
3. Re:The new AU ... by Anonymous Coward · 2012-09-14 06:04 · Score: 1
  
  Ah, they will tar-gzip it, and because of its uniformity, it will fit in a very tiny vault.
4. Re:The new AU ... by Anonymous Coward · 2012-09-14 06:11 · Score: 0
  
  If it were moving at relativistic speeds they wouldn't shut the doors in time, because everyone would be too busy trying to remember that relativity question from freshman physics. In the time it takes questioning why freshman relativity problems always involved barn doors, and if said barn door principles apply to vault doors, relativistic speeds cover quite a bit of ground.
5. Re:The new AU ... by Iamthecheese · 2012-09-14 07:37 · Score: 1
  
  technically possible if the bar can be bent
  
  --
  If video games influenced behavior the Pac Man generation would be eating pills and running away from their problems.
6. Re:The new AU ... by Anonymous Coward · 2012-09-14 07:48 · Score: 2, Funny
  
  It's already there, but you got the length wrong. It's exactly 1/149,597,870,700 AU
Eve nav problems by Anonymous Coward · 2012-09-14 05:39 · Score: 2, Funny

Great, everyone in Eve is going to be missing jump gates, plowing through asteroid fields at warp. Going to be chaos.
1. Re:Eve nav problems by Antipater · 2012-09-14 06:18 · Score: 1
  
  But without these precise calculations, you could fly right through a star, or bounce too close to a supernova! That'd end your trip real quick, wouldn't it?
  
  --
  Everything is better with chainsaws.
Oh great . . . by Traciatim · 2012-09-14 05:47 · Score: 1

Can someone come up with some sort of foot ball field to AU conversion chart or something?
New definition hasn't been embraced yet... by gx1400 · 2012-09-14 05:47 · Score: 1

Google still says: 1 Astronomical Unit = 149 598 000 000 meters 1 Astronomical Unit = 8.79057469 × 10^10 smoots
About fucking time! by Anonymous Coward · 2012-09-14 05:49 · Score: 0

It's about fucking time they fixed it. Does this mean we'll be getting a three day weekend now (finally)?
Correct. This makes no sense.
Not that anybody on Slashdot cares... by Guppy06 · 2012-09-14 05:50 · Score: 1

... because it's not an SI unit.
I'd have gone for 149,896,229,000m by wonkey_monkey · 2012-09-14 05:52 · Score: 4, Interesting

I know it's a bit out, but I'd go for 149,896,229,000m - exactly 500 light-seconds.

--
systemd is Roko's Basilisk.
1. Re:I'd have gone for 149,896,229,000m by Anonymous Coward · 2012-09-14 07:50 · Score: 0
  
  That just asks for redefining seconds and meters.
2. Re:I'd have gone for 149,896,229,000m by wonkey_monkey · 2012-09-14 20:24 · Score: 1
  
  I'd say the meter is the more arbitrary of the two, since the second is at least based on the duration of the Earth's orbit. I'd like a meter defined as the time light travels in 1/300,000,000 of a second, and an AU as 150,000,000,000m. Mmmm, lovely round numbers - what could possibly go wrong?
  
  --
  systemd is Roko's Basilisk.
3. Re:I'd have gone for 149,896,229,000m by Anonymous Coward · 2012-09-15 00:11 · Score: 0
  
  second is at least based on the duration of the Earth's orbit
  No it isn't. The second is defined as
  the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.
4. Re:I'd have gone for 149,896,229,000m by wonkey_monkey · 2012-09-16 18:56 · Score: 1
  
  second is at least based on the duration of the Earth's orbit
  No it isn't.
  I did say "based on" instead of "defined by".
  
  --
  systemd is Roko's Basilisk.
5. Re:I'd have gone for 149,896,229,000m by mick129 · 2012-09-20 10:32 · Score: 1
  
  I know it's a bit out, but I'd go for 149,896,229,000m - exactly 500 light-seconds.
  It's only 1434 kilometers away from 499 light-seconds.
  
  --
  Move along, no sig to see here.
In other news... by Anonymous Coward · 2012-09-14 05:55 · Score: 0

Our national debt is no longer astronomically high...
1. Re:In other news... by danbert8 · 2012-09-14 07:54 · Score: 1
  
  Actually if you printed out one dollar bills for the national debt it would go about 10 AUs at this point... Or you could do 1 AU with 10 dollar bills.
  (155.95 / 1000) * 16 027 000 000 000
  
  --
  Yes it's an anecdote! Were you expecting original research in a Slashdot comment?
Good news! by GodfatherofSoul · 2012-09-14 05:55 · Score: 2

Now when I read an article about an Oort cloud object 10,000 AU from the Earth, I'll know to scrub off that extra 2000 km from my mental model.

--
I swear to God...I swear to God! That is NOT how you treat your human!
Not a good measure... by tekrat · 2012-09-14 05:57 · Score: 1

I mean, how many Libraries of Congress is this new measurement?

--
If telephones are outlawed, then only outlaws will have telephones.
1. Re:Not a good measure... by jqpublic13 · 2012-09-14 06:04 · Score: 1
  
  That depends if you place the books end-to-end, stack them on top of each other, or rip our their pages and fold them into a complex daisy chain.
  
  --
  Non calor sed umor est qui nobis incommodat.
2. Re:Not a good measure... by Capt.DrumkenBum · 2012-09-14 06:38 · Score: 1
  
  I prefer to measure in Linguine.
  In that case: 787357214210.526631
  
  --
  If I were God, wouldn't I protect my churches from acts of me?
Thank you, Bob Barker. by Minwee · 2012-09-14 06:26 · Score: 4, Funny

Now that it's "Fixed", it's technically an Astronomical Eunuch.
I wonder how much AU is in ... by 140Mandak262Jamuna · 2012-09-14 06:28 · Score: 1

... lengths of football fields. Or school buses lined up end to end. Or number of King Georges standing with arms out stretched touching finger tips to finger tips stretching all the way from the center of Earth to center of Sun. That is the kind of units that makes sense. Not this convoluted French thingies that we don't even agree on the right way to spell, meter? metre? what the hell?

--
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
1. Re:I wonder how much AU is in ... by Anonymous Coward · 2012-09-14 09:22 · Score: 0
  
  A football field is around 100 meters, so 14,959,78,707
How much is that in Cesium atom wavelengths? by jfengel · 2012-09-14 06:29 · Score: 3, Funny

Or more correctly, units of c times the period of "radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom". Let's get this down to fundamentals and not muck about with intermediate convenience units like "meters".
the chronoss unit by Anonymous Coward · 2012-09-14 06:34 · Score: 0

damn this is even easier to remember
150 billion meters
wow add a few meters and its suddenly not hard to forget....sides i am da man
At last by NumenMaster · 2012-09-14 06:52 · Score: 2

We can rest easy now.

--
Where's my sock? There it is...
Need to do a new release of our calculator! by Anonymous Coward · 2012-09-14 06:57 · Score: 0

Hello,
I work for a company that makes graphical calculators... and we do handle AU.... and we just did a release...
and now we need to do another release to handle that new change...
crud!!
Ah, I love unit conversions... by Iniamyen · 2012-09-14 07:03 · Score: 1

Almost as much as I love speeding to work in the morning @ 0.000000032 parsecs per leap year.

Excuse me, I'm going to go cook my lunch @ 69 million Joules per day.
1. Re:Ah, I love unit conversions... by Lithdren · 2012-09-14 07:49 · Score: 1
  
  You drive to work at 546,818.7 miles an hour?
  
  And I thought my commute was bad.
2. Re:Ah, I love unit conversions... by Lithdren · 2012-09-14 07:56 · Score: 1
  
  Hate to reply to myself but I couldn't have screwed that calcuation more if I tried.
  
  Of course, trying again I came up with 0.017498198 miles an hour. So either way my point stands, asuming this one is any more accurate than my last blunder.
3. Re:Ah, I love unit conversions... by Iniamyen · 2012-09-14 08:09 · Score: 1
  
  http://lmgtfy.com/?q=0.000000032+parsecs+per+leap+year+to+mph
4. Re:Ah, I love unit conversions... by Anonymous Coward · 2012-09-14 08:10 · Score: 0
  
  Google says its about 70 miles/hr
5. Re:Ah, I love unit conversions... by darkHanzz · 2012-09-14 08:11 · Score: 1
  
  MMm google gives 112km/h, which is a zippy commute... try googling for: 0.000000032 parsecs per leap year in km/h
Kerning adjustment... by BubbaDave · 2012-09-14 07:08 · Score: 1

Kerning adjustment would have taken care of it.
Nobody takes the trouble anymore...
Dave
So why are we using it? by jgtg32a · 2012-09-14 07:22 · Score: 1

If the distance is going to be bouncing around for various reasons it sounds like it isn't a good measurement. Personally I've always liked using light second as a measurement.
Wow, you'd think by now by Anonymous Coward · 2012-09-14 07:43 · Score: 0

You'd think by now dumbass americans would be using a SANE measuring system. Why don't you dumb shits just measure it in football fields and be done with it?
Blah, blah, blah. Your beer tastes like horse piss. Blah, blah, blah overweight fat asses. Blah, blah, blah.
Why not 1 AU = 499.0047838 light seconds? by Anonymous Coward · 2012-09-14 07:55 · Score: 0

Why not 1 AU = 499.0047838 light seconds?
1. Re:Why not 1 AU = 499.0047838 light seconds? by mattr · 2012-09-14 14:14 · Score: 1
  
  Interesting but then depends on measurement of c and timing of a second.. whereas the standard length of measure is a meter.
  Still, you could call 1AU == 150 gm == 500 lightsecs
2. Re:Why not 1 AU = 499.0047838 light seconds? by maxwell+demon · 2012-09-16 00:28 · Score: 1
  
  It doesn't depend on measurement of c because SI fixes c at exactly 299792458 meters per second.
  It does depend on the second, but the current definition does, too, because the meter is defined as 1/299792458 of the distance the light travels in vacuum during 1 second (this definition is what fixes the speed of light). In other words, the meter is defined to be 1/299792458 light seconds.
  Which in turn means that the astronomical unit is now de facto defined to be exactly 1024642950/2053373 light seconds
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
my first thought.... by pjr.cc · 2012-09-14 08:30 · Score: 1

For some reason the first thing i thought of was this:
http://xkcd.com/927/
Which is only partially true... but lets face facts, there is a TONNE of old doco out there that'll depend on outdated AU measurements, so for decades astronomers will still be going "which AU unit are they using" (something engineers still deal with on a daily basis)
Aaaaaaaw.... by Anonymous Coward · 2012-09-14 09:08 · Score: 0

but I liked the idea of a constant that changed based on the day of the year...
rather by Anonymous Coward · 2012-09-14 09:17 · Score: 0

the earth's distance from the sun remains just as it was
Or rather, the earth's distance from the sun changes constantly, but in the same way it always has.
That's just stupid by holophrastic · 2012-09-14 09:43 · Score: 1

There's no point in a unit (AU) being a large multiplier of another unit. We have an entire metric system for that (well, some of us do). The nice part about AU was precisely that it represented something dynamic. I don't always care how far away some asteroid is to the metre. I want to know how far it is relative to the sun.
Microsoft right! Google wrong? by Anonymous Coward · 2012-09-14 10:53 · Score: 0

Well it looks like Bing got it right and Google is wrong. How sad :-(
http://postimage.org/image/updgk8uaj/
Good... by denelson83 · 2012-09-14 11:53 · Score: 2

...Now fix the kilogram.
Kilometers would be the accurate measure. by Anonymous Coward · 2012-09-15 04:09 · Score: 0

If it's 93 million miles to the sun, then a number around 149 million meters is far too short. ...should read KILOmeters...
1. Re:Kilometers would be the accurate measure. by maxwell+demon · 2012-09-16 00:53 · Score: 1
  
  If it's 93 million miles to the sun, then a number around 149 million meters is far too short. ...should read KILOmeters...
  Or 149 billion meters.
  
  --
  The Tao of math: The numbers you can count are not the real numbers.
150GM by AlleyTrotte · 2012-09-15 06:30 · Score: 1

Really I think a nice round number like 150GM that's 'giga meters' that would be much nicer and easy to remember
in SI units there is no disagreement by Chirs · 2012-09-15 10:01 · Score: 1

As log as you're using SI units giga will always be 10^9.
1. Re:in SI units there is no disagreement by doshell · 2012-09-15 11:01 · Score: 1
  
  And that was precisely my point.
  
  --
  Score: i, Imaginary