This is another photo from my trip down the river on Thursday 6th May. It is a view from the Queen's House in Greenwich Park, looking up towards the statue of General Wolfe on the left and Flamsteed's old Royal Observatory on the right. This is one of my favourite places in London. There happens to be the very faint image of a monoplane coming out of the cloud at the top right. (Click on the photo and use the magnifier!) I wasn't able to take a tour round the observatory since it was already packed out with visitors.
I did look in the National Maritime Museum and the Queen's House for a while, but the art exhibitions are in such dim lighting now, and I couldn't find the famous portrait of Stoker Martin that I remember seeing there. EDIT: I've added in a link to an article in Life magazine from 1948 which includes a copy of the portrait.