What is the diameter of the Earth and does it increase over time?
Eratosthenes
"Now the distance from S [Syrene] to A [Alexandria] was known by measurement to be 5,000 stades; it followed that the circumference of the earth was 250,000 stades. This is the figure given by Cleomedes, but Theon of Smyrna and Strabo both give it as 252,000 stades. The reason for the discrepancy is not known; it is possible that Eratosthenes corrected 250,000 to 252,000 for some reason, perhaps in order to get a figure divisible by 60 and, incidentally, a round number (700) of stades for one degree. If Pliny is right in saying that Eratosthenes made 40 stades equal to the Egyptian skoinos, then, taking the skoinos at 12,000 Royal cubits of 0.525 metres, we get 300 such cubits, or 157.5 metres, i.e. 516.73 feet, as the length of the stade. On this basis 252,000 stades works out to 24,662 miles, and the diameter of the earth to about 7,850 miles.Source: A History of Greek Mathematics (Heath 1921).
Theon of Smyrna
"Thus the whole diameter of the Earth would be approximately 80,182 stades. For three times this number plus a seventh of it was the perimeter of 252,000 stades."
Quoted from On Mathematics Useful for Understanding of Plato.
Also 7,850 miles.
Claudius Ptolemy
Ptolemy in the Geographia improved on the work of Eratosthenes. He calculated 1 degree as 500 stades, which using Heath's math works out to an Earth diameter of 5,607 miles.
Plus, according to one author, "he tended to overestimate the breadth of the whole known world." (Evans 1998)
Modern Measurements
Modern measurements are all over the place (as usual there is no scientific consensus). See here.
However, The North American Datum of 1983 (NAD83) [Schwarz, Ed., NOAA, 1989] was determined by the NGS to be 12,756.274 km (7926.75 miles) on the major axis (equatorial), and 12,713.504 km (7900.17 miles) on the minor axis (polar), with an average diameter of 12,734.889 km (7913.46 miles).
At least 76.75 miles growth in 2223 years.
-759725.jpg){kind=link}
19 comments:
Hi OIM Off topic, but you might find this of interest with respect to Peak Oil:
Peak oil: postponed
What the oil companies don't tell you
By Andrew Orlowski
Posted in Environment, 17th September 2008 11:05 GMT
Interview
Oil supplies will actually last for far longer than our politicians think, the scaremongers fear, and the oil companies tell us. So says Dr Richard Pike, head of the Royal Society of Chemistry, and someone who isn’t afraid to stir controversy. Whither, then, Peak Oil?
In a wide-ranging interview, Dr Pike talked about energy independence, Peak Oil, and how to educate our scientifically illiterate elites.
http://www.theregister.co.uk/2008/09/17/richard_pike_rcs_interview/
OIM claims: "Modern measurements are all over the place (as usual there is no scientific concensus [sic])."
The difference between the measurements of equatorial diameters you link to is 0.004%. At what level would you not consider it "all over the place"?
Most likely a simple round off error as measurements get more accurate with better methods or by averaging more measurements of the same method, but nothing really precludes the Earth's diameter from changing over time.
In actuality, the Earth and most spinning planets are generally thought to be oblate spheroids because of their angular momentum, and hence they buldge more at the equater than a perfect sphere would.
HOW ACCURATE WERE THE ANCIENTS?
That seems to be the relevant question, but it's a question that can't be answered with any degree of comfort or certainty.
What can be done with a much higher degree of comfort and certainty is to make exacting measurements, now, and then continue taking measurements into the future.
But that also leaves to the future the answer as well.
"Down the road," one theory or the other can be falsified.
BF:
Thanks for the interview.
The Register, September 17, 2008, Peak oil: postponed
This interview is well worth reading -- it rests on conventional "fossil" theory.
So, even with conventional assumptions, "Peak" oil is pushed out beyond 30 years away from today.
Beyond the 30 year economic horizon, it has no economic impact today.
Of course, changing the assumptions based on Abiotic Oil theory pushes "Peak" even further out. How far out, no one knows.
The price of oil today and for the foreseeable future (within the economic horizon) should not have one cent added based on "Peak" oil concerns.
"Peak" oil is a cruel hoax.
BrianR,
I would consider consensus (thx for editing my typos by the way) to be unanimity. There is none.
Unless you want to provide the authentic number for the diameter which so far you have failed to do. Should you find the exact diameter of the Earth I would encourage you to do so in the only way you consider to be valid -- namely publish it in a peer reviewed paper. If you are persuasive, you might be lucky enough to reach a scientific consensus, however since the Earth is growing it will be extremely short lived consensus.
"You only find complete unanimity in a cemetary." -- Abel Aganbegyan, economist, 1987
OIM ... you claimed modern measurements were "all over the place", I demonstrated that they are within 0.004% of each other and you respond by telling me that I have failed to produce an authentic number and I must publish a peer-reviewed paper on the Earth's diameter?
Weird.
I was simply trying to get a handle on your threshold for "all over the place" w/r/t measurement error. Is it safe to assume that regardless of what's being measured that unless multiple measurements are <0.004% then it's "all over the place"?
It's not really that big of a deal, carry on.
You're correct in saying the modern measurements are in the same general/gross range.
I thought it was weird when you told me to demonstrate my thoughts in peer reviewed papers as well...;)
No, you don't have to "demonstrate your thoughts" in peer-review literature, but you should cite it as much as possible for your claims.
I do; see links at left....=)
OIM says: "I do; see links at left"
Yes, a lot of those links do link to peer-reviewed papers (or press releases about peer-reviewed papers) but others link to non-peer-reviewed articles.
For the readers of this blog and others interested it would be nice to see a list of references all in one place ... in a format similar to this:
Author(s), Year, Title: Journal/Book/Proceedings/Special-Pub/Etc, Volume no. (if applicable), Page range (or # of pgs if book), Publisher (if applicable).
And, if a relatively recent pub the DOI # is very useful.
That way, the readers can easily track down the papers themselves in a library. Would be of great value for researchers.
COULDN'T HAPPEN TO A NICER GUY...RIGHT
T. Boone Pickens has been battered out of the market after losing two billion Dollars from his BP fund.
Pickens is an oil cheerleader that has been fanning "Peak" oil fears for years.
The only price direction Pickens was willing to acknowledge was up.
I guess he started believing his own press-clippings and took a sharp stick in the shorts.
Ya, he had the microphone up his ass, all right.
Now, Pickens has a folksy way about him which smooths over his arrogance.
Don't feel sorry for Pickens...feel sorry for all the shareholders who've lost their shirt investing in his fund.
CAN THE INTERNATIONAL ENERGY AGENCY BE TRUSTED?
Just in time to save the oil industry, the Interantional Energy Agency (IEA) has predicted dropping production levels.
Global Oil Production Is Falling Faster Than Expected, FT Says (Bloomberg) October 29, 2008.
"Annual production is set to drop by 9.1 percent in the absence of additional investment, according to the draft of the agency's World Energy Outlook."
But in the previously linked interview: The Register, September 17, 2008, Peak oil: postponed, Dr Richard Pike, head of the Royal Society of Chemistry, who prevously spent twenty five years in the oil industry, stated the oil industry and the agencies that monitor it constantly low ball the production figures for a variety of reasons.
Secrecy is the watchword in the oil industry.
With speculators always hoping to "bounce" another price wave,the oil industry has little incentive to provide robust production figures.
The oil industry benefits from price bounces.
Speculation in oil futures was illegal except for companies like airlines that had a business reason for long term oil contracts up until the late 1990's.
This was a long standing bi-partisan policy agreement.
Policy makers should revisit that policy to take the volatility out of the oil market.
Economies should not be held hostage to speculator's greed.
HALLOWEEN: HOLY, FRANKENSTEIN'S MONSTER.
An electric volcano.
"Igor, it's ALIVE!"
Picture published in the National Geographic Society magazine.
DOES IT TAKE $360 BILLION PER YEAR INVESTMENT TO SUSTAIN AND INCREASE PRODUCTION?
No question, the business of exploring & producing petroleum is expensive.
But is the IEA correct when it forecasts, "...that the rising consumption of China, India and other developing nations requires investments of $360 billion a year until 2030."
That seems like a high number to sustain. Is the IEA offering a justification for high oil prices?
What data does the IEA present to justify their Dollar amount.
What is the total world profits for all oil producers (both private and state owned)?
This IEA report generates more questions than it does answers.
For the oil industry, an old question comes to mind: "Who's watching the watchers?"
Anaconda, those Chetien pictures are absolutely amazing.
The following discovery reinforces the electromagnetic conection between Earth and Sun:
http://science.nasa.gov/headlines/y2008/30oct_ftes.htm?list22718
BF:
Thank you, quite a report.
The story goes a long way to confirm Plasma Universe theory. Science@NASA Magnetic Portals Connect Sun and Earth, October 30, 2008. "During the time it takes you to read this article, something will happen high overhead that until recently many scientists didn't believe in. A magnetic portal will open, linking Earth to the sun 93 million miles away. Tons of high-energy particles may flow through the opening before it closes again, around the time you reach the end of the page.
"It's called a flux transfer event or 'FTE,'" says space physicist David Sibeck of the Goddard Space Flight Center. "Ten years ago I was pretty sure they didn't exist, but now the evidence is incontrovertible."
Wow!
Here's another story (both are well worth linking to read the whole story) to light the Northern sky. Science@NASA Solar Superstorm, October 23, 2003 "Newly uncovered scientific data of recorded history's most massive space storm is helping a NASA scientist investigate its intensity and the probability that what occurred on Earth and in the heavens almost a century-and-a-half ago could happen again.
In scientific circles where solar flares, magnetic storms and other unique solar events are discussed, the occurrences of September 1-2, 1859, are the star stuff of legend. Even 144 years ago, many of Earth's inhabitants realized something momentous had just occurred. Within hours, telegraph wires in both the United States and Europe spontaneously shorted out, causing numerous fires, while the Northern Lights, solar-induced phenomena more closely associated with regions near Earth's North Pole, were documented as far south as Rome, Havana and Hawaii, with similar effects at the South Pole."
For the doubters of Plasma Universe theory, when you put these two stories together it paints a powerful picture.
There is evidence that energy and mass are added to the Earth, which causes some pretty fantastic fireworks. Maybe even expands the planet over time...
BF, Thanks again.
thank you for your blog, it help me with букмекеры and was interestin
Very interesting blog, it really helped me learn a great deal!too many interesting things Dog obedience training
Post a Comment