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How Far is One Degree


chacam
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I just tried using Google Earth to see the difference in longitude vs. latitude at my latitude (42˚ N) and up by Hudson Bay (60˚ N). I set three place marks at each location; two 1˚ of latitude apart while at the same longitude and one at the same latitude but separated by 1˚ longitude. There is definitely a difference, even at my latitude.

Edited by Iowa Tom
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degree (° or deg) [2]

a unit of distance sometimes used at sea, equal to 60 nautical miles, approximately 69.05 statute miles, or 111.12 kilometers. This distance is the average length of one degree of latitude (that is, the average distance between two lines of latitude 1° degree apart). Because the Earth is not exactly spherical, a degree of latitude actually varies from about 68.7 miles at the Equator to 69.4 miles at the poles. One degree of longitude is about 69.17 miles at the Equator (shrinking to nothing at the poles!).

 

from http://www.unc.edu/~rowlett/units/dictD.html

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(knocks the rust off the calculator, checks trig functions)

 

at equator, one degree is really close to one nautical mile, 68 or 69 statute miles or so.

 

The distance between two longitudes one degree apart varies by the cosine of the latitude, so

 

69*cos(29) gives 60.3 statue miles

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Longitude and Latitude are different in 1*.

 

You can use your GPS to determine this in any given degree.

Just make a waypoint at 1 degree apart and hit go to.

 

Any way here it is 69.2.... N-S and 55.4... E-W miles respectively.

 

That is why the BLM and others use what is called the Rectangular System of Measure the PLSS.

 

And at the Poles it is 0....miles.

The meridians converge at the poles.

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Latitudes ALWAYS stay equidistant: 69.047 statute miles (111.12)

 

Longitudes (as people have mentioned) converge at the poles.

 

One degree of Longitude at N 01° is 69.036 miles (111.103 km)

One degree of Longitude at N 25° is 62.577 miles (100.709 km)

One degree of Longitude at N 86° is 04.816 miles (007.751 km)

One degree of Longitude at N 89° is 01.205 miles (001.939 km)

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For what it's worth, my favorite place for all this great math stuff is Dr. Math at http://mathforum.org/dr.math/. And specifically this question: http://mathforum.org/library/drmath/view/61561.html.

 

Note this applies only for the folks who want to understand the math behind the answer, if you just want the easy answer without having to work for it, well there are the links posted above. <_<

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At 29 deg N Lat, what is the distance of one degree of Longitude? Is there a formula to determine measurements of this type for various degrees of Lat? My math is a bit rusty.

  Plugging the coordinates N 29° W 0° and N 29° W 1° into my Great Circle program for the HP48G, I get a range of 60.3894830926 statute miles — a bit more than the 60.3 miles that seems otherwise to be the most credible answer previously posted.

 

  It occurs to me that the exact answer that you're looking for would be along a “line” that stays at the same latitude while traveling a degree of longitude, and that this “line” would actually curve slightly, and thus be a bit longer than the straight line calculated by my Great Circle program.

 

The distance between two longitudes one degree apart varies by the cosine of the latitude, so

 

69*cos(29) gives 60.3 statue miles

  You ought to get an answer that is slightly longer than mine, and you got instead an answer that is shorter.  Let's see what I get when I duplicate your calculations:

«29_° COS 60_nmi *» gives me 52.4771824283_nmi  Converting to statute miles gives me 60.3896630287_mi, which is slightly longer than my Great Circle result (Very tiny difference — less than a foot).  Looks like your error was to round it off incorrectly.  You ought to have rounded it up to 60.4 rather than down to 60.3.

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That is why the BLM and others use what is called the Rectangular System of Measure the PLSS.

 

 

PLSS is the Public Land Survey System. Some people know it as Township, Range, and Section. It is based on a flat Earth, so every 4 townships there is (supposed to be) a correction factor. In the mountainous terrain of the western U.S. the surveying errors accumulated, so you see some bizzare shapes to some sections, which are supposed to be exactly 1 mile square. The notes of the surveyors (some dating from the 1850's in my area) make some real interesting reading. They describe encounters with grizzly bears, surveying right through Indian villages, forest fires, having their equipment damaged by floods, etc.

 

You may have heard of the fellow that first thought up this method of land surveying and mapping. His name was Thomas Jefferson (yes... THAT Thomas Jefferson).

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That is why the BLM and others use what is called the Rectangular System of Measure the PLSS.

 

 

PLSS is the Public Land Survey System. Some people know it as Township, Range, and Section. It is based on a flat Earth, so every 4 townships there is (supposed to be) a correction factor. In the mountainous terrain of the western U.S. the surveying errors accumulated, so you see some bizzare shapes to some sections, which are supposed to be exactly 1 mile square. The notes of the surveyors (some dating from the 1850's in my area) make some real interesting reading. They describe encounters with grizzly bears, surveying right through Indian villages, forest fires, having their equipment damaged by floods, etc.

 

You may have heard of the fellow that first thought up this method of land surveying and mapping. His name was Thomas Jefferson (yes... THAT Thomas Jefferson).

 

We try to use geocaching to help promote the profession of Land Surveying and this topic really insterested me. Some very good points are being made. Regarding the correction lines, see our cache Correction Survey Lines (GC122YE)

 

Or for some information about the PLSS see Correction The Survey Meridian (GC12F3R)

 

Burk

OSLS

Edited by BurkC
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By definition 1 degree is 1 nautical mile (about 6080 feet or 1.15 regular miles). Of course that's 1 degree north/south. If youre wanting to know east/west then you have to multiply by the cosine of your latitude. And if youre wanting to know at a random direction then Pathagoreas is necessary.

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By definition 1 degree is 1 nautical mile (about 6080 feet or 1.15 regular miles). Of course that's 1 degree north/south. If youre wanting to know east/west then you have to multiply by the cosine of your latitude. And if youre wanting to know at a random direction then Pathagoreas is necessary.

 

I really hate to nitpick, but if this were the case that would mean the distance from the north to south poles along the curve of the earth at sea level would be 180nm. One minute of latitude is one nm. With 60 minutes in one degree, that places the distance travelled between poles along the curve of the earth at sea level at a far more respectable 10,800nm.

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One degree of latitude is the same length (approx. 69 miles) everywhere on the globe, but the length of one degree on longitude varies depending upon where you are. One degree of longitude will vary from 0 feet at the poles to 69 miles at the equator.

 

Since a degree of latitude is approximately 69 miles, and a minute of latitude is approximately 1.15 miles. A second of latitude is approximately 0.02 miles, or just over 100 feet.

 

The longitude will vary by the cosine of the latitude.

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By definition 1 degree is 1 nautical mile (about 6080 feet or 1.15 regular miles). Of course that's 1 degree north/south. If youre wanting to know east/west then you have to multiply by the cosine of your latitude. And if youre wanting to know at a random direction then Pathagoreas is necessary.

 

Actually, I believe it's 1 minute (of latitude) that is equal to 1 nautical mile. One degree would be 60 nautical miles.

Edited by MtnGoat50
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