Now You See It, Now You Don’t - The Stones and the Stars: Building Scotland's Newest Megalith - page 23

F IG . 2.5 Galactic coordinates (Drawing by Nick Portwin)
with time. But for astronomical coordinates that are fixed over time
spans longer than human lives, we have to use galactic latitude and
longitude, whose zero point is the galactic center and whose pole lies
on the perpendicular to the plane of the Milky Way (Fig. 2.5 ) . The
Sun takes 200-230 million years to orbit the galactic center, so for all
but the nearest stars, galactic co-ordinates are effectively fixed even
beyond the spans of civilizations. You might suppose that galactic
coordinates could have no part in megalithic astronomy, but even
that seems not to be entirely true - see Chap. 5 .
References
1. Yates FA. (1964) Giordano Bruno and the Hermetic Tradition. Rout-
ledge and Kegan Paul, London
2. Turner, H.H.: A Voyage in Space . Society for Promoting Christian
Knowledge, London (1915). Includes two maps showing the Sun's
position within the cluster from different angles