Hampstead Observatory, the 100-year old telescope observatory in North London is open to the general public for free during the winter months – but has to close for summer due to the annoyance of a lack of darkness in the evenings.
This Saturday (15th May 2010) marks the final evening of operations until the evenings start to get dark enough again in September.
Saturn is currently the best sight in the night sky for visitors, and the observatory will be open 8pm-10pm on Friday and Saturday evenings.
The observatory is only open if the sky is clear enough to see anything, and weather forecasts suggest that Friday will be a write-off, with partial cloud on Saturday – so it could be working that night.
Will also open 11am-1pm on Sunday, but obviously not possible to use the telescope.
Web site of the HSS Observatory