Cleaning the observatory

Usually I am not in the observatory when I take pictures. All the more I noticed on the weekend how much dirt has accumulated in the observatory and on the dome over the winter. So give me the cleaning bucket!

 The weekend before Easter was supposed to be the first with warm temperatures, at night it was even starry - but the moon in the lion was too disturbing to take pictures at night. So I spent some time during the day in the observatory and used the nice weather to clean everything and prepare it for the spring season.
In the Internet there are some descriptions of the construction of a roof observatory, but you find very little about maintenance and care. Therefore, I simply describe how I keep my observatory in good shape, even if it might seem a little trivial.
Of course, I do not clean my optical surfaces with this method!
The floor is cleaned with a hand vacuum cleaner, the walls made of OSB boards are only wiped dry, all plastic surfaces I wipe with a microfibre cloth, which I moistened with lukewarm water with dishwashing soap. Cleanin the inner surface of the observatory dome takes lot of time and care, but after about an hour the dome is clean again and looks like new.
So I can still enjoy a roof observatory years after the construction, which looks like new.