Editing 2170: Coordinate Precision

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This cartoon gives increasingly precise latitude and longitude coordinates for a location on the planet Earth. However, a given pair of coordinates covers a trapezoidal region of land, and thus leaves some ambiguity; therefore, greater precision requires an increasing count of decimal places in your coordinates. This comic uses this information to roughly identify how precise a given coordinate length might be.
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This cartoon gives increasingly precise latitude and longitude coordinates for a location on the planet Earth. However, a given coordinate covers a rectangular region of land, and thus leaves some ambiguity; thus, greater precision requires an increasing count of decimal points in your coordinates. This comic uses this information to roughly identify how precise a given coordinate length might be.
  
 
The increasing precision of coordinates in this cartoon are similar to the increasing magnification in the short documentary {{w|Powers of Ten (film)|"Powers of 10,"}} which can be found [http://www.youtube.com/watch?v=0fKBhvDjuy0 here].  (Also parodied in [[271|#271:Powers of One]]).
 
The increasing precision of coordinates in this cartoon are similar to the increasing magnification in the short documentary {{w|Powers of Ten (film)|"Powers of 10,"}} which can be found [http://www.youtube.com/watch?v=0fKBhvDjuy0 here].  (Also parodied in [[271|#271:Powers of One]]).
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The coordinates at [https://tools.wmflabs.org/geohack/geohack.php?pagename=Cape_Canaveral&params=28.52345_N_80.68309_W_type:landmark_region:US-FL_scale:10000 28.52345°N, 80.68309°W] (in {{w|decimal degrees}} form; in {{w|geographic coordinate system}} form using degrees, minutes, and seconds, 28° 31′ 24.4″N, 80° 40′ 59.1″W) are pointing to the {{w|Rocket Garden}} at the {{w|Kennedy Space Center}} in {{w|Merritt Island, Florida}} —specifically, the tip of the [https://www.kennedyspacecenter.com/-/media/DNC/KSCVC/Blog-Images/Rocket-Garden/rocket-garden-with-labels.ashx?h=860&w=1173&la=en&hash=7B9ADC7AFF5370E462AC98D9651945B806B77B2C Delta] rocket.
 
The coordinates at [https://tools.wmflabs.org/geohack/geohack.php?pagename=Cape_Canaveral&params=28.52345_N_80.68309_W_type:landmark_region:US-FL_scale:10000 28.52345°N, 80.68309°W] (in {{w|decimal degrees}} form; in {{w|geographic coordinate system}} form using degrees, minutes, and seconds, 28° 31′ 24.4″N, 80° 40′ 59.1″W) are pointing to the {{w|Rocket Garden}} at the {{w|Kennedy Space Center}} in {{w|Merritt Island, Florida}} —specifically, the tip of the [https://www.kennedyspacecenter.com/-/media/DNC/KSCVC/Blog-Images/Rocket-Garden/rocket-garden-with-labels.ashx?h=860&w=1173&la=en&hash=7B9ADC7AFF5370E462AC98D9651945B806B77B2C Delta] rocket.
  
The sixth entry in the table, with seven digits of precision, includes the caveat that, while your coordinates map to areas small enough on the Earth's surface to indicate pointing to a specific person in a room, "since you didn't include datum information, we can't tell who". This is a reference to the ''{{w|geodetic datum}}'' or ''geodetic system'' — different ways of dealing with the fact that the Earth is neither perfectly spherical nor perfectly an oblong ellipsoid. The various datums do not make much difference at six digits of precision, but at seven, there is enough skew depending on which system is in use that the person in a room you are referring to with the coordinates is ambiguous. It is unstated, but the remaining lines in the table with ever-greater precision suffer from this same issue and are equally ambiguous without datum information.
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The sixth entry in the table, with seven digits of precision, includes the caveat that, while your coordinates map to areas small enough on the Earth's surface to indicate pointing to a specific person in a room, "since you didn't include datum information, we can't tell who". This is a reference to the ''{{w|geodetic datum}}'' or ''geodetic system'' — different ways of dealing with the fact that the earth is neither perfectly spherical nor perfectly an oblong ellipsoid. The various datums do not make much difference at six digits of precision, but at seven, there is enough skew depending on which system is in use that the person in a room you are referring to with the coordinates is ambiguous. It is unstated, but the remaining lines in the table with ever-greater precision suffer from this same issue and are equally ambiguous without datum information.
  
 
The final entry, with seventeen digits of precision, suggests that either the user is referring to individual atoms in the much-larger-scale whole-Earth coordinate system, or (perhaps more likely) has not bothered to format the values from the GPS module for viewing in the software UI in any way whatsoever, resulting in a value that is {{w|False precision|meaninglessly precise}} because the measurement wasn't that {{w|Accuracy and precision|accurate}} to begin with. See [[2696: Precision vs Accuracy]]. Even if the value is accurate, locating individual atoms by coordinates is not actually useful in most cases, and the motions of multiple systems within our physical world (continental drift, subtle vibrations, {{w|Brownian motion}}, etc.) would render the precise value obsolete rather quickly.
 
The final entry, with seventeen digits of precision, suggests that either the user is referring to individual atoms in the much-larger-scale whole-Earth coordinate system, or (perhaps more likely) has not bothered to format the values from the GPS module for viewing in the software UI in any way whatsoever, resulting in a value that is {{w|False precision|meaninglessly precise}} because the measurement wasn't that {{w|Accuracy and precision|accurate}} to begin with. See [[2696: Precision vs Accuracy]]. Even if the value is accurate, locating individual atoms by coordinates is not actually useful in most cases, and the motions of multiple systems within our physical world (continental drift, subtle vibrations, {{w|Brownian motion}}, etc.) would render the precise value obsolete rather quickly.

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