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==Explanation==
 
==Explanation==
Cueball and Megan have found a {{w|survey marker}} on the ground. Survey markers such as these are used as reference points for the {{w|North American Datum|NAD 83 and NAVD 88}} geodetic reference systems, and the {{w|U.S. National Geodetic Survey}} has a database storing the coordinates of these markers. However, those two systems are being replaced by the {{w|National Spatial Reference System#Datum of 2022|New Datums of 2022}} (delayed to 2024-2025), which is primarily based on satellite systems and gravimetric models.
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{{incomplete|Created by a GUIDED MISSILE THAT MISSED THE TARGET DUE TO COORDINATE DRIFT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
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Cueball and Megan have found a {{w|survey marker}} on the ground. Survey markers such as these are used as reference points for the {{w|North_American_Datum|NAD 83 and NAVD 88}} geodetic reference systems, and the {{w|U.S. National Geodetic Survey}} has a database storing the coordinates of these markers. However, those two systems are being replaced by the {{w|National_Spatial_Reference_System#Datum_of_2022|New Datums of 2022}} (delayed to 2024-2025), which is primarily based on satellite systems and gravimetric models.
  
When they update the database in the comic, Cueball's position, both horizontal and vertical, changes to compensate, leaving him panicking in mid-air. In reality, updating a database to change the coordinates of a location would not physically move items at the location.{{Citation needed}} Arguably, if they did, no one would notice much, since everything surrounding them should similarly move simultaneously to its corrected position as well. On the other hand, if the markers were updated and moved relative to each other, and (as the comic suggests) items shifted based to match the new markers, this could mean that objects would be stretched or compressed depending on whether the new markers were closer or further away from each other from their previous positions. However, in the comic, the only things whose position is 'known' (and can therefore be 'corrected') are those that are directly on a marker, hence why this shifting does not seem to apply to Megan (or her phone).
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When they update the database, in the comic Cueball's position changes to compensate. In reality, updating a database to change the coordinates of a location would not physically move items at the location. Arguably, if they did, no-one would much notice, since everything surrounding them should similarly move simultaneously to its corrected position as well. However, this shifting does not seem to apply to Megan, still standing next to the survey marker.
  
The title text refers to NAD 83 being around 7 feet off. This probably refers to the difference of {{w|North American Datum#Comparing NAD 83 to WGS 84|about 7.2 feet (2.2 m)}} in the positioning of the centers of the notional Earth ellipsoids used as the basis for NAD 83 and {{w|World Geodetic System|WGS 84}}. This is also one of [[Randall]]'s [[:Category:Fun fact|fun facts]].
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The title text refers to NAD 83 being around 7 feet off. This is in reference to both WGS84 and presumably the New Datum.
  
 
Absurd outcomes from differing survey standards was also the topic of [[2888: US Survey Foot]].
 
Absurd outcomes from differing survey standards was also the topic of [[2888: US Survey Foot]].
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:Cueball (off-panel): I love finding these survey markers. It's somehow reassuring.
 
:Cueball (off-panel): I love finding these survey markers. It's somehow reassuring.
  
:[Cueball and Megan are shown as they look down on the marker. Cueball has one leg on either side of the marker and Megan stands to the right.]  
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:[Cueball and Megan are show as they look down on the marker. Cueball has one leg on either side of the marker and Megan stands to the right.]  
 
:Cueball: I like that someone, somewhere, knows where this spot is.
 
:Cueball: I like that someone, somewhere, knows where this spot is.
 
:Cueball: If I stand on it, they know where '''''I''''' am.
 
:Cueball: If I stand on it, they know where '''''I''''' am.
  
:[Cueball and Megan look up at each other.]
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:[Cueball and Megan looks up at each other.]
 
:Megan: But the NAD83 and NAVD88 datums are getting replaced soon. That marker's coordinates could shift by like 5 feet.
 
:Megan: But the NAD83 and NAVD88 datums are getting replaced soon. That marker's coordinates could shift by like 5 feet.
  
:[Megan is looking down at her phone in her hand, standing in the same place in relation to the marker. Cueball is now floating in the air behind her about 5 feet above the ground, while flailing with his arms and legs (as shown with three small curved lines at the end of either arm and above and below him).]
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:[Megan is looking down at her phone in her hand, standing in the same place in relation to the marker. Cueball is now floating in the air behind her 5 feet above the ground, while flailing with his arms and legs (as shown with three small curved lines at the end of either arm and above and below him.)]
 
:Megan: Oh look, it just got updated.
 
:Megan: Oh look, it just got updated.
 
:Cueball: '''''Hey! Put me back!'''''
 
:Cueball: '''''Hey! Put me back!'''''
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[[Category:Comics featuring Megan]]
 
[[Category:Comics featuring Megan]]
 
[[Category:Geography]]
 
[[Category:Geography]]
[[Category:Fun fact]]
 

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