I'll have to guess here
..... the domed building next to the WTC (Deutche Bank?) hadn't yet been built?
You are the man TB! Great eye!
As a matter of fact I am pretty sure that in 1979 the entire waterfront area, across from the WTC, along the river, which is now called The World Financial Center / Battery City, was still just wetlands that consisted of weeds and high grass. I don't believe that it started to be developed until the very early eighties.