Basic SAR Geometry Question

Hi all,

In the metadata included in S1 L1 products, in each geolocationGridPoint it is included the “azimuthTime”, for each point. How can the azimuthTime be different for each pixel? shouldn’t be the azimuthTime, defined in Sentinel-1 Product Specification as “Zero Doppler azimuth time to which grid point applies [UTC]”, constant for all values in the same line?
As it remarks that it is at “Zero Doppler”, I understand that it refers to the line perpendicular to the antenna at a specific moment, ie azimuthTime, and it should not depend on the pixel. Could anyone spot where is the faulty assumption?

Most probably this is not the place for such a question, if so I kindly ask if anyone could point me in the right direction or appropriate forum.

Thank you very much for your help,

You may want to read on coordinate systems used for SAR SLCs and the zero doppler model specifically that S1 uses:

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