The event (which I shall call X) occurred on July 21st. A Guildford man (who I shall call Y) made an observation of X on that day, and this was reported in a major scientific journal a few days later. Y was a pillar of the local establishment and a well-respected amateur astronomer. In the years that followed there were other X events but the only one of relevance to this cache is the one first observed by Y.
The X events have had a large cultural impact - inspiring writers, film-makers, artists and musicians. However, the public's interest in X has waned over the years. Rather than attracting serious researchers like Y, it now seems that only hopeless romantics or conspiracy theorists are drawn to this subject. Some disbelieve Y's evidence entirely and claim that X was a hoax.
When you have identified X and Y you should be able to work out some numbers:
The year that X happened (ABCD)
The year that Y was born (EFGH)
The year that Y died (JKLM)
The day of the year this (his death) was (NPQ)
Age when he died (RS)
Letters in his middle name (T)
Letters in his surname (U)
The cache is hidden near to where the observation of X was made.
To find its co-ordinates start from those given above
Then to the Northing add P.GDU and subtract J.HTM
and to the Westing add T.CQN and subtract N.QDR
You can check your answers for this puzzle on Geochecker.com.
The cache is a 670ml clip-top plastic container. It contains a hint for my puzzle cache "Edwards Invisible Sundial" GC1V77A. ( visit link )
Good luck, and please don't leave any spoilers in your log.