The long nights are back
It was properly dark by half past seven last night. In June I sit on the back step at eleven and the sky is still blue in the north, so this is the time of year when astronomy stops being a late-night activity and becomes something you can do before dinner. When the clocks go back at the end of the month it will be dark before I have finished washing up.
To mark it I have started a small project that I may or may not keep up. Once a week, on any clear night, I will count the stars I can see inside the square of Ursa Minor, the bowl of the Little Dipper. Same spot on the step, twenty minutes for my eyes to adjust, no optics. The idea is to see whether my sky is getting worse as the town replaces its old orange street lamps with white ones.
First count: six. The street lamp was on, the neighbour's kitchen light was on, and I have no idea whether six is good. I will know in a year.
For comparison, and partly as a consolation, here is a minute of time-lapse from the European Southern Observatory's La Silla site in Chile. Not mine: ESO filmed it, and I have never been anywhere near the southern hemisphere.
The domes turn and open, and the whole sky wheels round the south celestial pole, which has no bright star marking it. The two fuzzy patches that drift through, about half way, are the Large and Small Magellanic Clouds, neighbouring galaxies I will probably never see with my own eyes. The Milky Way in that footage has more structure than I have seen in total from my garden.
It does not make me want to stop counting six stars over a street lamp. It makes me want to go and count them more carefully.