Slashdot Mirror
Milky Way Is Twice the Size We Thought
Peter writes to tell us about a research group at the University of Sydney in Australia, who in the middle of some calculation wanted to check the numbers everybody uses for the thickness of our galaxy at the core. Using data available freely on the Internet and analyzing it in a spreadsheet, they discovered in a matter of hours that the Milky Way is 12,000 light years thick, vs. the 6,000 that had been the consensus number for some time.
Yeah, it comes with "%30 MORE!" now.
Obesity is everywhere.
Wikipedia says it's only 1000 light years thick.
So until now everyone was just measuring the radius of the Milky Way?
Using data available freely on the Internet and analyzing it in a spreadsheet, they discovered in a matter of hours that the Milky Way is 12,000 light years thick, vs. the 6,000 that had been the consensus number for some time.
I'm going to have to go with the Biblical numbers on this one and use the 6,000 figure.
The theory of relativity doesn't work right in Arkansas.
This is a good reminder how you're supposed to dig down to the raw data and validate that. I remember reading in one of Richard Feynman's books about a similar case, some conclusion or data appeared well supported, because a lot of the research papers were supportive of the idea, but it turned out that they derived what they said based on a single source.
The case here is similar, it's a good reminder how science is about data, validation and facts not about authority. You're supposed to check your data, check your facts and try to avoid making implicit assumptions.
It takes a man to suffer ignorance and smile
Be yourself no matter what they say
So I read the article (yeah, yeah - I know...I was bored) and I hope the spreadsheet software used wasn't Excel - we all know how well that counts.
The Mothership
What have you done today?
Is there any physical effect where a galaxy ends? Or are we just talking about an imaginary limit.
How hard is it to map the galaxy? If we don't know where the stars are, we can't know the size. If we know, we don't need it; we can describe the actual, real, shape.
Where's the flaw in my logic? (I hope it's in the part about the limit being imaginary, I like limits in Space like the heliosphere)
Snickers is only about half the size
Does this ruin dark matter? Perhaps our mass estimates for our own galaxy were off by a factor of 2.
have they checked their freely available sources they found on the internets? seriously i'm dubious of everything claiming to use a spread sheet and/or internet sources these days.
If you mod me down, I will become more powerful than you can imagine....
this is the super size version?
Sig?
'cause I think I'm supposed to know but I don't, but how does the tag "montypythonwaswrong" relate to this story?
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
It's only ~ 1.4426 times as big as we thought in log scale...
Historical measurements of the galactic core's thickness by noted astronomer Monty Python resulted in a value of 16,000 light years, much closer to 12,000 than the previously accepted 6,000. The new light shed on this ancient knowledge should remind us all of Eristosthenes' measurement of the of the circumference of the earth, later confirmed to within 1%. Of course, less well known were Eristosthenes' dialogues on the Iberian Inquisition.
Perhaps they confused the commonly accepted radius for the commonly accepted diameter:
d = 2 * r
Now you guys tell me!
What the Fudge man, I have been eating Snickers all this time thinking I'm getting more chocolate! Now I find this out?
What we're seeing now is middle age spread.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Well, if we're expecting that the universe is actually 75 to 95 percent dark matter based on the
SAME KIND OF FLAWED DATA, perhaps we are underestimating the amount of matter we actually CAN see.
I always wondered how exactly they determined how much matter was in the universe, indirect evidence or not.
Seems like there may be few assumptive leaps there, upon which we build our entire cosmological understanding.
If the 'missing' matter is actually regular matter that we haven't found, or have found and discounted,
the search for dark matter will be even more in vain than it appears to be already. Can we stop looking?
That famous scientist may have allowed himself to get carried away a bit. What it means is that there was no clean breakthrough article. Rather, evidence gradually accumulated. What it does not mean is that the connexion is "perhaps true", certainly not in the current stage where effective medicines exist.
On the other hand it's good practice to have roundup articles that go over the evidence.
Use something a layman could understand OK?
Say, how many Library of Congress, or elephants, have we got here?
"It bulges in the middle, sixteen thousand light years thick, But out by us it's just three thousand light years wide"
Being fair at that age it must take quite a while to get an erection.
The spiral arms are thicker than we've been assuming. Does that mean that there are more stars and gas/dust clouds in the greater volume? If there are more, then the mass of the galaxy is higher, and with the relativistic adjustment recently adopted, there's less need for a "dark halo", or, at least, less of one required to balance the velocity of the outer stars. OTOH, if there's the same amount, then the density is less, which throws off the very measurement technique that they're using to derive the new thickness, since the less-dense interstellar medium will have less effect on the two wavelengths (yeah, I read the article).
Anyone know of an online resource for the American Astronomical Society papers? I'd like to see what, if anything, they say about the density values for the WIM.
...We are told that the sun's light takes approx 8 minutes to reach us, but now we know that the distance involved is twice as much so therefore the speed of light must be approximately double what we thought! ...if the moon is twice as far away as previously thought, how come astronauts have landed successfully - in theory, they should get 'there' and be in the middle of nowhere ...UNLESS, of course they never went....AH HA!!!
AT&ROFLMAO
What I find disturbing is the fact that a number is this widely off and no one discovered it for such a long time! I can imagine deviation by x % or less where x
The split of Humans from the Apes pushed back by another 6 to 7 million years earlier than previously thought based on molecular genetics. The difference from the earlier estimate of around 5 to 6 million years is therefore over 100%
http://www.news24.com/News24/Technology/News/0,,2-13-1443_2169361,00.html
When you say "light year" you mean a "low fat year"? Or it goes all the way to "fat free year".
P.S.: You may want to check your data, a year is a long time to stay under 3 grams of fat per serving.
Wikipedia isnt a reliable source? Where on earth is this mysterious relable source? The best you can do is list information while citing sources, but thats not even totally reliable. Id still bet wiki is far more reliable than most the crap you read online about a topic.
Whenever life gets you down, Mrs. Brown,
And things seem hard or tough,
And people are stupid, obnoxious or daft,
And you feel that you've had quite eno-o-o-o-o-ough...
Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour,
That's orbiting at nineteen miles a second, so it's reckoned,
A sun that is the source of all our power.
The sun and you and me and all the stars that we can see
Are moving at a million miles a day
In an outer spiral arm, at forty thousand miles an hour,
Of the galaxy we call the "Milky Way".
Our galaxy itself contains a hundred billion stars.
It's a hundred thousand light years side to side.
It bulges in the middle, sixteen thousand light years thick,
But out by us, it's just three thousand light years wide.
We're thirty thousand light years from galactic central point.
We go 'round every two hundred million years,
And our galaxy is only one of millions of billions
In this amazing and expanding universe.
(Animated calliope interlude)
The universe itself keeps on expanding and expanding
In all of the directions it can whizz
As fast as it can go, at the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is.
So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth,
And pray that there's intelligent life somewhere up in space,
'Cause there's bugger all down here on Earth.
"Our galaxy itself contains a hundred billion stars. It's a hundred thousand light years side to side. It bulges in the middle, sixteen thousand light years thick, But out by us, it's just three thousand light years wide."
This is not a sig
young man, very clever... But it's turtles all the way down...
The NASA source doesn't specify at what radius the thickness is measured, leading me to believe that the "1000 light years" figure references an average, or representative, thickness. According to the summary (although curiously unmentioned in TFA) this new discovery seems to pertain specifically to the Milky Way's thickness at the Galactic core, where it is substantially thicker than at points located further down the arms (as illustrated in this side view).
SIERRA TANGO FOXTROT UNIFORM
Mmmm. Double-sized Milky Way. aaaaagggggcccchhhh (drools).
From TFA with commentary:
Proving not all science requires big, expensive apparatus, Professor Gaensler and colleagues...downloaded data from the internet
No, this actually proves that you can reuse data gathered with large expensive apparatus. There's a difference. They couldn't have done this without expensive infrastructure that just happened to cost them nothing (or close to nothing) - ie. The original instruments and the Internet.
The University of Sydney team's analysis differs from previous calculations because they were more discerning with their data selection. "We used data from pulsars: stars that flash with a regular pulse," Professor Gaensler explains. "As light from these pulsars travels to us, it interacts with electrons scattered between the stars (the Warm Ionised Medium, or WIM), which slows the light down.
Well now wouldn't you want to explore why the data differs so much, before declaring your answer to be the correct one just because you verified your calculations are correct?
My first thought is: Did they use some standard or average value for the density of the WIM? Could the discrepancy be because the WIM itself is not uniform through the thickness of the galaxy/
This is definitely an interesting result and worth following up but rather than declare victory the real question is why is there such a large discrepancy with other data?
These posts express my own personal views, not those of my employer
Genesis 1:32 And God typed
Perhaps the differences in quoted thicknesses are the result of different definitions of the edge?
TFA says: "The team's results were presented in January this year at the 211th meeting of the American Astronomical Society in Austin, Texas." but there's no indication of where the results have actually been published in a peer-reviewed journal so that one could read the paper for oneself. I looked on the AAS site and couldn't find anything there either. So, pending access to a detailed published per-reviewed account of their work, I'm reserving judgement as to how valid the claim is.
My first thought was it referred to the choccy bar 'Milky Way' and got all excited.
I want a list of atrocities done in your name - Recoil
When we can just study the universe via Google?
This space available.
Don't you think that it is strange that the number was multiplied by 2 (from 6000 to 12000) ? How convenient!
Why not find a number such as 13100 or 9884? This number is just too clean to be true. It's only value way be to show that our last estimation was way wrong, but it doesn't tell how false is this new estimation...
The name of the scientist you are reminded of is most likely Kary Mullis. He got a Nobel prize for inventing PCR. An interview with him on the topic of AIDS can be found here http://www.virusmyth.com/aids//hiv/cfmullis.htm
Possibly, you were thinking of Peter Duesberg, a Berkley professor. He has a website on AIDS here http://www.duesberg.com/
It requires solid raw data to establish the HIV->AIDS causative link because the symptoms of AIDS (acquired immune deficiency syndrome) can have many potential causes. For example, stress and malnutrition can also leave your immune system in tatters. So it is certainly reasonable to question the evidence and call for more data.
It still won't ruin your appetite!
They would have figured this out sooner, but the 12,000 light year measuring tape had not been invented yet. Now we know for sure!
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." Albert Einstein
Scientist fumbles calculation; Doubles galaxy by accident
Bot Assisted Blogging
Something else that is now OVER 9000!!!!!111
So every time someone forget to divide by 2 , he is going to claim he came up with a major discovery ??
What does the spreadsheet say about the glaxy's thickness?
Shiny. Let's be bad guys.
Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
Perhaps the reason for your confusion is that NASA is stating that DISK is 1000 lt yrs thick while the article is talking about the so called bulge which is a more or less sphereical bulge in the center of the Galaxy.
I am an astronomer, so first some background: The Milky way has several components: young stars, old stars, dust and various components of gas. They all have different thicknesses. There is no single "thickness". One of these components (warm ionized gas) has been measured to have a thickness larger than expected. This measurement has not been confirmed by others, nor (I think) published yet.
Despite this complexity, this discussion thread is awash with arguments, confusion, wild speculation, suggestions that dark matter might be wrong etc. etc. OK, fine, this is slashdot, that's what slashdot is for.
But the same people (presumably) have also rushed off to edit Wikipedia! (I see a half dozen edits this morning, to add in the "new" thickness.) That's the part that I find incredible. And people really take Wikipedia seriously?
Modern scientific theories are all falsifiable, meaning, there is always a theoretical counter example that could possibly disprove the theory. This falsifiability is the reason why these theories evolve and get overwritten - they get falsified.
Falsifiability is also Science's greatest weakness because it guarantees the existence of counter examples. On scientific terms, the opposing party must also use only falsifiable material. This keeps information in check, and ensures that the debate remains scientific. However, when the falsifiabilitiy requirement is abandoned, Science easily loses to those who do not understand or obide by it. Unfalsifiable truths are undisbutable.
This is why when Faith (of any kind) arms minds with unfalsifiable theories, they can not only refute science with certainty and ease, but they can also refute opposing Faiths. When two undisputable truths contradict, the only choices are to ignore, to forgive, or to fight - for there is no common ground.
Apart from Faith, we can also find many examples of unscientific debates taking precedence over scientific ones in the media and in politics. Attempts to misinform the public are made by sponsoring counter-theory campaigns, and these work very well, because the majority is usually incapable of judging scientific basis. This is why it is extremely important for scientific debates to be conducted by scientists, and why science seems so unconvincing at times when presented by someone else.
Unfotunately none of this will change, as long as science is faithful to falsifiability.
An admin deleted a link because the UK's Prime Ministers office wasn't considered an authoritative source on House of Lords reform. When Wikipedia lets it's admins practice group think and self evident bias daily, it cannot be considered creadible.
"and analyzing it in a spreadsheet" - Why even include that? Is it supposed to bolster our confidence in the data? `Cause it doesn't... it detracts.
We now think Milky Way is twice the size than what we had previously thought. Using "is" makes it sound like they actually know how big it is this time around.
As the island of our knowledge grows, so does the shore of our ignorance.
You really CAN get stuff on the net to double your size.
I doubt it'll make very much difference - after all, it's only a change of one order of magnitude. That's peanuts to space.
I'm not surprised that astronomers' estimates of the galaxy's thickness are off by half. I've seen observatories... they only point their telescopes up.
Looks like we need more SGC teams to vist all of it.
"Using data available freely on the Internet and analyzing it in a spreadsheet ,"
I certainly hope they didn't use Microsoft Office 2007 for this calculation....
"I bow to no man" - Riddick
***GUARANTEED increase your galaxy by 6,000 light years***
thick and sturdy clusters. ladies love dark matter. hawking beautiful einstein copernicus keppler cassini
jplab buzz lightyear wormhole
[sorry--I couldn't resist]
I might know what I'm talkin' about, but then again, this is Slashdot...
...they discovered in a matter of hours that the Milky Way is 12,000 light years thick, vs. the 6,000 that had been the consensus number for some time.
Look, I don't know why we have to constantly defend the well established consensus of Galactic Thinning from these deniers. The science is done, we have a scientific consensus that the galaxy is 6,000 light years thick, now we have these two amateurs coming in and using, of all things, an Excel Spreadsheet to try and prove us wrong.
Clearly, these denialists should just be ignored.
But, if I had my way, we'd have a Nuremberg trial for these denialists.
What's that? Global Warming?
Sorry, wrong consensus.
Life, the Universe, and Everything... in my image.
does this effect Dark Matter, Missing Mass calculations so that they balance now? (or are a smaller magnitude?)
Lifes a game play to win!
The joke was referring to a bug that was new to Excel 2007, where the number 65,535 was interpreted as 100,000 (the parent apparently remembered it the other way around). Excel 2007 added quite a few bad calculation bugs - heres an article about some of them.
These are the people who helped the "TIME/LIFE apes" come to pass through a combination of bad science and media's lack of concern for the truth. [The ape-to-man display that shows a monkey on one end, an accountant on the other, despite some of the 'apes' being out of place by millions of years, and despite deciding what one of them looked like based on a single tooth...]
These are the people who are constantly telling us about distant celestial collisions and saying "That's what'll happen to us in 54 billion years" even though the information is a) completely useless to anyone with a heartbeat and b) a guess, at best.
And isn't it these people...and the [theoretically] trying to convince us that a) change to the climate is going to kill us b) We're the cause and c) we have any control over it whatsoever and d) it can be solved by sending people money, despite the fact they can't forecast THE WEATHER more than a week ahead?
Now, am I to understand that these brilliant, bastions of faith who we should 'absolutely trust' with our immortal souls, since they're so much more accurate than the Bible....NOW TELL US THEY'VE MIS-MEASURED OUR GALAXY BY A FACTOR OF TWO??!?!?!?! OUR OWN GALAXY? ONE WE CAN ACTUALLY "SEE" FROM HERE? (Consensus isn't science.)
We've been trusting science for far too long.
--- For a good time mail uce@ftc.gov
Then it won't be possible to do anything for free.
Are you sure your not making the same mistake they did with the Mars probe and mixing inches and centimeters? Better check.
Well, it wasn't an intentional mistake.
:)
The guy who measured it had his thumb on the Milky Way, and you have to remember that the Milky Way is mostly vacuum. He squished it flat by mistake
The above comment should be used to edit the summary, which is highly misleading.
to fatten us all up on larger milky Way bars.
Tsukasa: All I really want, is to be left alone...
Now I have to pack an extra suitcase.
It must have been something you assimilated. . . .
"Infrequent Anonymous Cowards Reliable on Wikipedia":
http://slashdot.org/article.pl?sid=07/10/17/2249246
Also, consider just how skewed the mean edit is on Wikipedia: typical edits don't change the substance of an article, but rather are copy and continuity edits. Even if an edit requires extensive copy editing and retrofitting because of sloppy writing, the substance survives. If an edit musters some modicum of clarity and compositional awareness, it's going to need even less editing and be less susceptible to simple syntactic and transcription breaking. Slashdot discussed this a while back too:
Who (Really) Writes Wikipedia
http://slashdot.org/article.pl?sid=06/09/05/1210241
The space science, planetary science, astronomy, astrophysics and cosmology articles on Wikipedia tend to be in dire need of improvement at this point. Dilettantes and worse, partisan dilettantes run roughshod over any part of these articles that aren't articulated clearly, correctly, and hopefully with citations. BUT! The parts that are clean tend to stay clean, unless some partisan crank pseudo-science enthusiast tries to win an edit-war. However, these are rare and fixed quickly.
The point is that even a single, small edit has a good chance of getting long-term traction, and this chance improves in some significant proportion to the quality of the edit. Quality really does count for something on Wikipedia. Facts are stubborn things.
That page is still broken as of this moment. If you are still convinced such an edit is not worth your time, perhaps you will consider a meta-edit: why don't you post the content you already posted in your Slashdot comments on the Wikipedia talk page where they will do some good?
They COULD have used an abacus. Then tabulated things on a set of papers spread across the campus. Then, with a TI calculator as a backstop, the spreadsheets derive from the abacus values.
There. Spreadsheets. Abasheets, Spreadacus...
Alternatively, they might have modeled it in a CAD program with units set to parsecs. (No, it doesn't have to be AutoCAD. They might have used TurboCAD, DesignCAD or whatever can model in infinite units, as long as they choose convenient values that won't end up with results orders of magnitude off.
Now, what will become of Celestia, and all the other programs that might have used the now-debunked (seemingly-debunked) disk thickness/core distance? Will there be a patch showing the historically-taught distance limits vs the apparent/new/revised "north"/"south" limits?
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
I've also contributed to the growth of the Galaxy.
Patents Drive Free Software as Hurricanes Drive Construction Industry
especially "scientists" who claim to be able to tell me "big things" like the age of the universe, the speed of light, the size of the universe, and all this other crap.
These morons get it wrong as often as they get it right.
How many times in my lifetime has the "size of the universe" been increased? I'll bet about a dozen times. I remember reading at least one article where one guy essentially doubled the size overnight.
One would conclude by now that nobody KNOWS the "size of the universe", rather than suggesting that "well, we're getting better at it."
This is not a general neo-Luddite rant against science. It's simply a reasonable skepticism that certain facts can be known precisely in the absence of being able to SEE or MEASURE them directly, rather than by convoluted methods that depend on everybody getting it right. That kind of thing is like programming - you end up with bugs, not perfection.
Richard Steven Hack - This sig is TOO GODDAMN SHORT TO DO ANYTHING USEFUL WITH! MORONS!
That NASA estimate is for the disk, which I imagine is much thinner than the core. You can't really compare them. It might still be wrong, though that is a separate matter.
Total cost of the Iraq war: about $500 billion.
1 light-year = about 5,900 billion miles.
Which makes a light year about 12 * (cost of war in Iraq so far) * (mile/$)
(If you want a more precise number, use 11.83.)
VLOOKUP was so useful.
It's all the fault of man. We must change our ways before this widening trend destroys us all!
Comment removed based on user account deletion