We revisited the 3 amazing stone circles above Boot for the Equinox. I noticed going home that the Sun still had a while to set and it was beyond 6pm. Now on Equinox, logic would say to me that sunrise should be 6am and sunset 6pm. That got me thinking. It probably works at sea level on the Greenwich Meridian in this country. Sunset is always later here on the west coast than in London. Today we are 15 minutes later than in London but that doesn't account for all of the time difference I noticed. This article explains about which part of the Sun the measurement is taken from and also about equilux day.