The nights that never quite get dark

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At this time of year the Sun sets after half past nine and never sinks far enough below the horizon for the sky to go properly black. Astronomical darkness, the point where the Sun is 18 degrees down and twilight stops interfering, barely arrives here in late June, and on some nights it does not arrive at all. At one in the morning there is still a pale glow along the northern horizon, sliding slowly eastwards, where the Sun is passing not very far beneath it.

Last night I went out at 00:30 anyway. Vega was overhead, Arcturus orange in the west, and the Moon, a waning crescent, not yet up. I could see perhaps four stars inside the square of the Little Dipper's bowl. In January the same patch shows seven or eight. The Milky Way, which on a dark August night runs through Cygnus almost directly over the house, was not there at all.

So, for now, someone else's. The US National Park Service released these few seconds of the Milky Way over a Joshua tree into the public domain:

The Milky Way over a Joshua tree0:06NPS/Glauco Puig-Santana, via Wikimedia Commons. Public domain. Original.

It is very short. Watch the band of light behind the branches rather than the tree, and notice how much structure there is in it: dark lanes, brighter clouds, the whole thing looking more like weather than stars. That is what a desert sky does. Mine will do a weak imitation of it in about six weeks, once the nights lengthen again.

Meanwhile the evenings are for baking and for sitting outside with no particular purpose, which is not the worst arrangement.