quote:
2) 60 Year festivals don't match the 50 year orbit, but do
match a 50 year orbit + 10 year journey time (Sirius is
approx 8.7 light years away).
This objection makes no sense to me. Why would you add the journey time to the duration of the orbit ?
Suppose the position we want occurred in 1800 and that there is a ten-year journey time. It will be visible on Earth in 1810.
With a 50-year orbit the next time that position occurs will be in 1850 and it will be seen in 1860 (1810 + 50 years). And the next one will be visible in 1910 and the next in 1960.
On the other hand the ceremonies with a 60-year cycle would be held in 1870 (10 years late), 1930 (20 years late) and 1990 (30 years late).