I've always said that we all have pieces to the puzzle Shan, and you've provided a very good one indeed. Can you provide a link to the NASA Scientist, Friedemann Freund, paper?

In regards to your theory, Photon's are charged particles, and a charged particle can be influenced by an electromagnetic field. The magnetosphere and ionosphere fit into this catagory. I'm not sure how photons are affected however.

We also know that mass bends light, as shown from our recent studies of light from stars bending around planets. Perhaps the shifting mass of our planet causes a slight variation in the path.

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