How to clear\define the coordinate system of a particular layer in catalog of ArcGIS Pro?
How to clear\define the coordinate system of a particular layer in catalog of ArcGIS Pro?
This option appears to be not available in ArcGIS Pro
This idea is already discussed here
How to define the coordinate system of a layer while working in catalog of ArcGIS Pro,
Yes, I agree, we need to be able to clear the coordinate system of both the map/data frame and the datasets themselves. Please add this functionality back into the Esri software/ArcPro.
Just a couple of examples of how I use it to ensure data quality and correct positioning of datasets. First, when I receive data with an unknown coordinate system (or an incorrect one applied to it), sometimes the person providing the data cannot tell me what the coordinate system is (might be old data and that info is lost to time). Often, I can work out what the coordinate system is by looking at the coordinates it displays as 'unknown units' in an ArcMap data frame/map or ArcCatalog preview that has no coordinate system assigned to it. This can be enough information for me to know which coordinate system it is in because I know the coordinate numbers I expect in different locations, or in the least, I can tell if it is geographics or projected. The unknown units show me this. Then I can test my ideas by defining the projection/coordinate system, seeing how it looks, if not quite right, I can clear that from the dataset and apply a different system. This requires both the ability to view the data in a data frame or Catalog view without a coordinate system set, plus the ability to then clear the coordinate system from the data frame as well as from the dataset after it has been defined.
Another example - sometimes we get CAD data where it doesn't draw in the correct/expected position. It might have the correct projection defined, or might be an unknown coordinate system. Again, I add it to a ArcGIS view that is clear of any coordinate system - and sometimes the unknown units reveal to me that there are just too many numbers in the coordinates - this can mean the CAD data is in millimetres, rather than the metres that the projected coordinate system uses - so then I know I just have to go into the Esri coordinate system and change the scale factor or linear units to get it back to metres.
Only ArcMap has this though - I cannot find this functionality in ArcPro or the ArcCatalog geography preview available in ArcPro (that does not display any coordinates when you hover over the spatial data). Please bring this to ArcPro.
I tried the “unknow” option in ArcGIS Pro 3.4.2 and it appears to work fine.
In the screenshot below:
The coordinate system of the map is “Palestine 1923 Palestine Grid.”
The coordinate system of one of the layers is “Palestine 1923 Palestine Grid,” and the other is “Israel TM Grid.”
Now, in the case where these two layers are added to a map 
If the coordinate system of the map is set to “Unknown,” then the two layers will be displayed using their absolute units.
