The night sky over Norway was there all summer. You simply could not see it.
The reason we see stars in autumn and almost none in June is not that the stars come back. It is that the darkness does. In southern Norway the night does not get properly dark at all for roughly four months, from late April until around 20 August. The sun sets, but it does not sink far enough. This week, for the first time since spring, true astronomical night has returned over Oslo.
The sky does not fill up
Astronomical night is the part of the day when the sun sits more than 18 degrees below the horizon. Only then is the sky dark enough for the faintest stars to break through. In Oslo that state does not exist at all between roughly 22 April and 20 August. It is the same mechanism that keeps summer nights light.
So when you step outside at eleven o'clock now and count three times as many stars as you did a month ago, the sky has not gained anything. The air above you has stopped shining.
The same reversal applies to the loveliest thing you can see on such a night. A shooting star looks like a star falling. It is not. It is a splinter of rock from space, often the size of a grain of sand, hitting the atmosphere at somewhere between 11 and 72 kilometres per second, around 80 to 120 kilometres above your head.
And it is not the stone that glows. It is the air in front of it.
The speed compresses that air so hard and so fast that it reaches thousands of degrees and shines. The streak you see is a tunnel of glowing air. The grain of sand itself is gone within a second.
This is what makes the sky such a good entry point into STEAM learning: a child observes something ordinary, guesses at the obvious explanation, and finds out it is wrong. Autumn is full of shifts like this — see also the first signs of autumn.
Try it at home: count stars through a cardboard tube
Lie down on a blanket somewhere no lamp points straight at you. Wait ten minutes without looking at a screen — eyes need that time, and one glance at a phone sends you back to the start. Ask the child to guess how many stars will fit inside an empty cardboard tube. Then hold it towards one patch of sky and count. Write down the number and the time, and repeat a week later at the same hour, aimed at the same spot.
Then try this: look straight at the faintest star inside the tube — and then shift your gaze slightly to one side of it. What happens?
Every child is made of good atoms — and the atoms in their body were made inside stars like these, long before the Earth existed.
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