That's the very aircraft - well done tredigraph! Google Maps is great stuff, isn't it?
If you zoom out a bit and look straight to the right, you see the rail track curving gently and intersecting Calle de Estrabón - so you can see one large building that blocks most of the view of the aircraft from the train.
In any case, yes, it does indeed appear to be a DC-8 - thanks a bundle, now I will be able to sleep peacefully tonight!
Though it does appear that this one does indeed have low-bypass engines, not the high-bypass ones I thought it had.
The Aircraft
DC-8 (from Wikipedia)