David O'Keefe wrote (in part):
>It seems to me that these designs refer to the
>Northern Lights, perhaps dancing about a center polar point, whose coming
>signalled the return of all vegetative and animal life below.
Without wishing to sound rude, one thing needs to be straightened out.
The Northern Lighs are not centered over the geographic north pole but
rather over the magnetic north pole which lies (on a map) in northwest
Canada. This is why one can regularly see them from the nothern US.
Yes, Ireland is located at a higher latitude than the contiguous US but, if
one were to redraw
the latitudinal lines, centering the meridians on the magnetic pole, you
would then see ireland to be signifigantly _lower_ than say ,Michigan.
The magnetic poles do move somewhat but, on a human timescale, they have
not varied much (polarity does shift relatively more frequently though).
Solar anomalies can, periodically, make the "Northern Lights" visable in
the most unnorthern regions of the hemisphere, but this is rare.
At least one person from Europe (Northern Ireland) has written in
to say that he has rarely seen them. I can second this, having spent six
years in northern Germany and "vacationing" along the North Sea, I have
never seen them at all.