# Talk:Orders of magnitude (length)

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## Error in length at the table

am must be E-18 fm must be E-15 pm must be E-12 nm must be E-9 μm must be E-6

[[User:halilkilic/HalilKilic (talk) 12:57, 25 June 2011 (UTC)]]

## Error in Universe Size

The page says (under "approx. diameter (comoving distance) of the visible universe"): 92 × 10^9 light years = 9.2 × 10^26 m = 920 Ym

I think the meters are wrong; a light-year isn't an "even" multiple of meters, so the numbers ("92" and "9.2") can't be the same.

My calculation gives: 8.798479339500144 m for 92E9ly. Can someone please verify this? Digulla (talk) 09:51, 7 June 2009 (UTC)

## Examples moved from metre article

• Gigametre
• diameter of the Sun is 1.4 Gm
• mean radius of Mercury's orbit is 57.9 Gm
• light travels the distance of 1 Gm in approximately 3.34 s
• Terametre
• the mean radius of Saturn's orbit is 1.43 Tm
• the mean radius of Neptune's orbit is 4.50 Tm
• light travels the distance of 1 terametre in 56 min
• Petametre
• the distance from the Sun to Proxima Centauri is 40 Pm
• the distance from the Sun to Sirius is 81 Pm
• light travels the distance of 1 Pm in 39 days
• Exametre
• the distance to Betelgeuse is 4 Em
• light travels the distance of 1 Em in 105.7 years
• Nanometre
• Femtometre
• It is commonly used in measuring the diameter of atomic nuclei. The diameter of an atomic nucleus is up to about 15 fm. Neutrons and protons are about 1 fm in diameter.

## millimetre redirect

Hi,
I post this here, since I reckon the odds of anyone reading my message will be higher here than on the millimetre talk page.
Now here is the question: can anyone tell me why millimetre does not redirect to metre? I was looking here following the suggestion to merge the articles on arcsecond, arcminute and maybe even degree (see arcminute talk page), since the former two are both subdivisions of the latter. My thought was that if there is a convention on Wikipedia on redirection of subdivision of units, at least keywords like millimetre would comply.
MHD 10:06, 8 February 2006 (UTC)

## Error?

### Question 1

Is the value correctly stated for "wavelength of the lowest UHF and highest VHF radio frequency, 300 MHz"?

--Richard Ong 06:13, 21 March 2006 (UTC)

I assume you mean the overlap? By definition: VHF = 30 MHz - 300 MHz and UHF = 300 MHz - 3 GHz. The boundaries are defined to simple numbers simply for easy of use. In reality there is only a fuzzy boundary. An example is the visible spectrum where it's difficult to see where one color begins and another ends.

 This is especially obvious with the red-orange boundary:

Another example is taking a gradient from black to white and trying to define where gray is.

Philosophically, we make just not be sophisticated enough to see the boundaries (like looking at things through a window covered in mist).

Zephalis (talk) 00:00, 24 April 2011 (UTC)

### Question 2

"average width of human hair (ranges from 18 to 180 µm)"

Does that not make it 99 µm, rather than 80?

--Thangalin 13:00, 27 Sep 2006 (PST)

No. You're assuming that the distribution is symmetric about the average. The frequency could fall off faster in one direction than the other. --Strait 20:14, 27 September 2006 (UTC)

## Possible merger

There are many pages such as 1 E20 m which are basically covered by this page. Shouldn't they be merged? --PhiJ 17:43, 21 March 2006 (UTC)

Oppose merger, separate pages allow more examples and give you better idea of the scales of the Universe. Additional material like diagrams could be included in these articles.--Jyril 19:19, 21 March 2006 (UTC)
oppose — Merging all those examples into one page would make for a terribly cluttered page. Getting rid of the examples is not a good option, either, since the examples are a good way to give people a sense of scale, even if they don't recognize all of the examples. One-dimensional Tangent (Talk) 22:16, 25 March 2006 (UTC)
oppose — The challenge is we want to show various views of the data set. Different breadths of scale, and different topical emphases. There is no catch-all view - different views clarify and obscure different things. Right now we have the way too long to see the whole picture Orders of magnitude (length), the assorted peephole 1Enn pages (great for accumulating facts, less good for providing context), and unassociated topical pages (eg, Grain size for small non-"astronomical" rocks). What's needed is not fewer tables, but more. A brief several oom per line, a readable one line per oom, etc. Anon 17:00, 26 March 2006 (UTC)

Many pages link to specific 1Enn pages. Eg, Special:Whatlinkshere/1_E4_m. So Orders of magnitude (length) would need id= tags Help:Anchors added to support this, no? So the redirects can do the right thing?

Some of the 1Enn pages are just lists of factoids, and look like Orders of magnitude (length) excerpts (eg 1 E-9 m). But others provide interesting categorization (eg 1 E0 m) or discussion. Perhaps the former should be merged and the latter not? Are the ones with other content contiguous?

How does this all evolve? Would 1 E-9 m be un-merged if someone was ready to enhance it like 1 E0 m?

It seems this has been discussed in the past [[2]].

Well, I'll remove the merge tags, and maybe try to do the suggestions some time, if/when I get the time. --PhiJ 18:31, 27 March 2006 (UTC)

## Links to 1 Ex m pages

I think we need links on this page to pages like 1 E11 m, but where do we put them. I was thinking that we could put them where it says 1011m, but I thought I'd try to get consensus before going ahead. --PhiJ 16:30, 17 April 2006 (UTC)

In my opinion it would be useful and interesting to add an additional feature to this page. Or, alternatively, another article if this one would become too crowded (likely). To get an even better idea of some of the enormous scales involved, we could add comparisons with known/imaginable entities. I already added something like this for the 'lightyear' (the time it would take voyager to cover such a distance), and I also added some distances covered by running/cycling/automobile races which accomplishes the same, but it could be expanded further.

Like, how long for a hypothetical airliner flying to the sun? Or how long would it take to walk around the earth? JH-man 19:35, 4 May 2006 (UTC)

DO IT! DO IT!! and if you don't do it here, tell me where I can find such a table! Sys Hax 01:33, 5 January 2007 (UTC)

• I've never created an article from scratch and I'm not sure I would be good at it. ButI would certainly try to contribute if someone started one. JH-man 09:00, 5 January 2007 (UTC)

## New Jersey State Highway 59

SPUI, I have no idea why removing this entry is so important to you? Neither is it to me, but each time you head-over-heals remove it, you destroy the layout of the table as well! Not an example of carefulness...

You say it's not the shortest highway. If that's your reason, then replace it by the shortest one instead of scrapping it.

If you think something like the "shortest highway" deserves no mention in this list, then at least say so. Personally, I think this kind of 'trivia' has its place here. It gives it a lighter touch. Let's deal with this like grown-ups. --JH-man 16:30, 16 July 2006 (UTC)

I have no idea what the shortest highway is. Route 59 is just a random short road that someone decided to add for the hell of it. --SPUI (T - C) 15:47, 17 July 2006 (UTC)

## Removed depth Titanic

I corrected two rowspan-errors. One by adding one row, one by simply removing the new entry. I really don't think the depth of the Titanic in the ocean is relevant enough in this list... In a way, this 'sense of scale' is already covered in the list by mentioning the deepest part of the ocean. This is both a 'record', and relates to a fundamental sense of scale of the earth. This in itself wouldn't be reason enough, but it is also a very 'invisible' quantity. People can not check out the depth of the Titanic with their own eyes, so as a comparison it is quite useless.

I am happy that you agree about the usefulness of a 'comparison'-page, though  ;-)

JH-man 09:00, 5 January 2007 (UTC)

## Insert...

...obvious penis joke.

## Exameter

For the blank spot on Exameter, how about the distance to some stars with extrasolar planets, such as 79 Ceti or HD 209458, or the diameter of a typical globular cluster? --LRG 00:24, 20 August 2007 (UTC)

Sounds good. Distances to the nearest known extrasolar planet, distance to the nearest known earth-like extrasolar planet and/or nearest planet with properties suitable for life-as-we-know-it? I'd say go ahead... JH-man 07:40, 20 August 2007 (UTC)

Should we remove the links to unit names such as petameter and exameter since they just forward to metre? --LRG 00:24, 20 August 2007 (UTC)

## Full stop vs. commas

I attempted to standardize the use of commas and periods in this article for the sake of consistency, but my edits were reverted. As it stands, the article is very confusing because there is no agreed upon use of commas vs. periods to indicate thousands and millions as opposed to tenths, thousandths, etc. I don't care which is used, but I do think the article suffers from a lack of clarity until this is standardized. X3210 (talk) 05:28, 8 January 2008 (UTC)

Regardless of your honorable intentions, your edits were reverted because they introduced thousand-fold errors. It seems to me such a "standardization" as you propose could easily lead to a worse lack of clarity. As the table is presently set up, the units change every decade, or every few decades, as indicated in the "Multiple" column. The values appear to be expressed in the conventional way for each range. Sometimes that involves multiples and sometimes fractions. I can see that that might lead to some confusion. However, attempting to "improve" the scheme would probably make matters worse. Please let's not fix it if it ain't broke. I doubt there would be a consensus for change. Perhaps we will hear from others on this. Hertz1888 (talk) 05:58, 8 January 2008 (UTC)
P.S. The article consistently uses a period as a decimal point (as opposed to the European use of a comma), in keeping with WP:MOS. There is no ambiguity. Hertz1888 (talk) 06:15, 8 January 2008 (UTC)

## Bot report : Found duplicate references !

In the last revision I edited, I found duplicate named references, i.e. references sharing the same name, but not having the same content. Please check them, as I am not able to fix them automatically :)

• "Asteroid-planet?" :
• The exact [[Solar_System#Terminology|category]] (asteroid/dwarf planet/planet) to which particular solar system objects belong, has been subject to some revision since the discovery of [[extrasolar planet]]s and [[Trans-Neptunian object|trans-Neptunian]] objects
• category

DumZiBoT (talk) 22:19, 8 August 2008 (UTC)

## Too many?

I found it such a grate article. But perhaps it's too big and should have no more than two examples per order of magnitude, to make clearer the concept of order of magnitude.--200.125.56.226 (talk) 20:17, 13 August 2008 (UTC)

## Re-Ordered the Units

To add clarity, I ordered the paragraphs giving examples above differently. For SI prefixes greater than one I went from smaller to larger, for those less than one I went larger to smaller.
GeoPopID (talk) 14:50, 19 October 2008 (UTC) - Sorry ! I don't know who or how to ask a question- to get a page corrected!! on Orders of magnitude (area) the earth figures appear to be incorrect - they sould be square Kilometres not metres, (land, sea - in fact everything after 10^11)?? thanks —Preceding unsigned comment added by 202.68.83.16 (talk) 20:56, 27 November 2008 (UTC)

The Big Picture
10x m
itsy bitsy ...
-15 atoms parts of (subatomic) electron, proton, neutron
-12 atomic hydrogen, oxygen, molecules
-9 tiny nanometres protein, integrated circuit, virus
-6 microscopic bacteria, cell, sand
-3 familiar millimetres & inches
everyday stuff
0 metres & yards
3 kilometres & miles
astronomy 6 solar system planets Continents, Ceres, Earth, Jupiter
9 orbits Sun, orbits of the inner planets
12 orbits of the outer planets; heliosheath
15 galaxy (Milky Way) light year; parsec distance to the stars
18 kpc Local Bubble, galactic arms
21 Universe million light years Large-scale structure of the cosmos
24

Derived from How Big Are Things?.

I love the idea of putting a summary table at the beginning. But I propose changing some of the words in it to be more encyclopedic; namely, "itsy bitsy", "everyday stuff", and non-descriptive words like "tiny" and "familiar". Also, maybe some column headings would be useful, as it really just seems like a collection of miscellaneous data right now. I'll gladly tackle this if nobody is opposed. TWCarlson (talk) 14:39, 14 November 2008 (UTC)
Itsy bitsy? That's encyclopedic? Can't we find something a little more formal, scientific and, above all, grown-up? Hertz1888 (talk) 00:16, 19 November 2008 (UTC)
Itsy bitsy? Is that an officially accepted term? Serendipodous 16:09, 22 November 2008 (UTC)
Not to my knowledge. It seems to be a form of baby talk. Due to lack of comment in defense of the term, I am taking the liberty of changing that section's name to "subatomic", matching the term used in its sole sub-section in the lead table. Perhaps an even more appropriate name will be found later, but I trust this will do for now. Hertz1888 (talk) 17:47, 23 November 2008 (UTC)
I never thought "itsy bitsy" was encyclopedic - I wanted to change it. Since it seems like a lot of people agree with me, I am going to change some of the other terms that I mentioned wanting to change. @Hertz1888, thanks for adding subatomic - that's much better. TWCarlson (talk) 15:49, 3 December 2008 (UTC)

## Arbitrary section titles

I think the idea of breaking the table into sections is good, but it is really arbitrary (according to the history, it is based on somebody's personal website, not any encyclopedic information). "Atoms to kilometers" is really not helpful to me...it basically covers the entire scale of distances (and more) that a human is likely to encounter. I'd like to change them to something more useful. I'd almost rather just break it up and say "10^-15 to 10^-6", and have section names like that to be more objective. TWCarlson (talk) 14:37, 5 December 2008 (UTC)

## clickable image for the 10^-6 to 10^5

In response to a request to make a clickable image for the 10^-6 to 10^5 metre "Human Scale" range, I am listing possible images for each component thumbnail. Here is a quick list of icon-like images so far that seem to match each relevant scale, although I feel better images must exist. I'll wait a few days for better examples and create a a couple of example collage.

1e-6 PD
1e-6 CC-BY Laura Bassett

1e-5 PD

1e-4 PD
1e-4 GFDL 1.2 or later

1e-3 PD
1e-3 alternative PD

1e-2 PD
48 pixels

1e-1 PD (to be mirrored)
48 pixels

1e0 PD
48 pixels

1e1 PD
48 pixels

1e2 PD
48 pixels

1e3 PD
48 pixels

1e4 PD
48 pixels

1e5 PD
48 pixels

84user (talk) 02:55, 6 December 2008 (UTC) (added more: 84user (talk) 13:52, 18 April 2009 (UTC))

## clickable imagemap for Human-scale section

I have finally cobbled together the above public domain images into some image maps:

And this image map uses slightly larger 64 pixel squares:

84user (talk) 18:39, 18 April 2009 (UTC)

## imagemap using timeline markup?

The Graphical timeline of our universe has a visual impact that seems better than just numbers and text. So, I tried to make a version for lengths instead of times. It's more difficult that I thought. Here's an example using the <timeline> markup, in case anyone wants to develop the idea further: 84user (talk) 19:54, 20 April 2009 (UTC)

## "Geographical" section

The Trans-Siberian railway, the Trans-Canada Highway and the Great Wall of China are not astronomical. Nor is the Mariana Trench really on a human scale. There needs to be a median scale, "Geographical" to go between human scale and astronomical, beginning at 1 km and ending at 10,000 km. I'd make it myself but I can't split the image maps. Serendipodous 13:57, 9 October 2009 (UTC)

## Nonsense nested exponents

$10^{10^{10^{122}}}$

There's no reason to show nested exponents, and there's no clarity what it means in any imaginable way! SockPuppetForTomruen (talk) 04:13, 1 October 2011 (UTC)

If no one objects, after allowing a reasonable time for comment, I would be amenable to your removing the above from the article. Whoever put it there originally must have seen some reasonable basis for inclusion. Hertz1888 (talk) 04:32, 1 October 2011 (UTC)
If the data is so offensive to some, be my guest. I just thought that some researchers would be interested in the incredible numbers scientists are coming up with these days and the mind-boggling size of our universe. Who could tell that a calculation made by a protégé of Stephen Hawking would be irrelevant/nonsense? Chasrob (talk) 14:39, 2 October 2011 (UTC)
That sounds to me like an objection, albeit a backhanded one. I should think the hypothetical maximum size of the universe would interest non-researchers as well. Hertz1888 (talk) 16:18, 2 October 2011 (UTC)
This is a table of "orders of magnitude". Without this entry the limit is 27, WHICH IS larger than the universe at present! WITH this last crazy entry, the limit is $10^{10^{122}}$!!!! That's not an order if you can't write it out as a number!!! SockPuppetForTomruen (talk)
Well, I just added another one. I don't think information should be outlawed simply because it is difficult to understand. If you want, we can include a note explaining the nature of double exponent notation. Serendipodous 19:58, 14 April 2012 (UTC)

## 1 E3 m

Should 1 E3 m be a redirect to this page or to 1 kilometre? --Ushau97 (talk) 13:14, 8 April 2013 (UTC)

I think it should redirect to 1 kilometre, as that is a more specific article on the subject, rather than this general Orders of magnitude page. Similarly with other articles, e.g. 1 E2 m should redirect to 1 hectometre 86.156.156.19 (talk) 13:20, 8 April 2013 (UTC)

## Planck length - quantum foam

It says here that quantum foam is an example of Planck length (10e-35m). However, the latest is that quantum foam is <10-48m. People have a tendency to assume that the Planck length is a limiting factor for a lot of things to which it does not apply. For the example, there's no reason why a photon couldn't have a wavelength many orders of magnitude shorted than the Planck length. For references, try searching on "quantum graininess" (or "quantum foam") and "10-48 m". You'll get plenty of hits, along with explanations. Or try this: ESA.INT Zyxwv99 (talk) 18:48, 16 July 2014 (UTC)

## removed images & imagemaps

I removed the images and imagemaps (one of them being broken) because they added nothing useful. They merely cluttered and confused an otherwise nice listing. – JBarta (talk) 11:36, 20 August 2014 (UTC)