Oddly, although before I made this reply the front page of the website said the latest reply was from Duncan, and the total number of replies before this one was given as 23 with the last made by Duncan 5 hrs 57 mins ago (at time of typing), the number of actual posts was shown as only 22 with nothing visible from Duncan. An aborted reply, or a glitch somewhere?
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Supporting amateur astronomers since 1890