Why are all points displaying in the ocean near Africa?

[MartinMccloud]

Creating centroids from a world country polygon layer. After displaying the XY Data all points show up in the ocean near Africa? I verified all geographic and projected coordinate systems are the same. See full workflow above. 

[DanPatterson_Retired]

The coordinates are being treated as planar values.

When you created the event layer, you should have defined its coordinate system as a Geographic Coordinate System, most likely a GCS WGS84.  Without the definition of what it is, it won't be projected to what you want it to do.  I would also suggest that you move on from an event layer and save/export it to either a geodatabase featureclass or shapefile.  

As a side note, make sure that you get the centroidX and centroidY the rightway around (X is longitude and Y is latitude... not quite sure how the centroid values were created)

[MartinMccloud]

Thanks for the quick response Dan! 

[JayantaPoddar · Accepted solution]

Rightly pointed by Dan, it's an issue with the Coordinate System - Coordinate Values mismatch.

WGS_84_Web_Mercator (Auxiliary Sphere) is a Projected Coordinate System. Thus, its units are in Meters. When you add the values (in Decimal Degrees) using Web_Mercator, it considers the units to be in Meters, instead of Decimal Degrees.

Here is what you need to do (choose any one of the following).

1. While using Calculate Geometry for calculating Centroid, you can keep the default units, i.e., don't change the units to decimal degrees. Then the values will be correct when you add data in WGS_84_Web_Mercator (Auxiliary Sphere).

2. If you want the XY values in Decimal Degrees (Calculate Geometry), then choose the Spatial Reference as GCS_WGS_1984 while Adding XY Data (as pointed by Dan).

3. If you have ArcGIS Desktop Advanced License, you could use Feature To Point—Help | ArcGIS Desktop. 

[MartinMccloud]

Thank you for the detailed response! I am a novice user so providing the steps I needed to fix the issue was awesome!

[MichaelTomiak_Quercus]

I found the above didn't quite apply to my situation, as I alreayd had  X and Y coordinates captured as part of a photo image layer.
An alternative is to simply 'Redefine' the projection to the GCS WGS 1984 (using the 'Define Projection' tool). 

A temp error came up saying "this layer already has a projection defined (the Webmercator PCS -WKID 3857) - but just accpet it and override it. 

Tip: if 'Define Projection' is greyed out when you first try on your (imported) layer, right-click the layer and 'Export To Features' to create a copied editable layer to then redefine the projection.