“After midnight, we’re gonna let it all hang out…”
The Perseids: this shower of “shooting stars” does not peak until 12 August, activity is already underway. And it is a great year to observe the Perseids because moonlight will not interfere to drown them out.
As with all meteor showers, the meteors are produced when the Earth ploughs through a stream of dust left by a comet orbiting the Sun and they flare in our atmosphere.
They are called Perseids because, if you trace their streaks backwards, they appear to radiate from a point in the constellation of Perseus. This is an effect of perspective, like straight rail tracks converging to a distant point, and in fact the meteors are travelling on parallel paths.
The comet responsible for the Perseids was Swift-Tuttle. The dust particles in space, called meteoroids, and about the size of grains of sand, are now spread right along the swarm’s orbit. This means we see Perseids every August. They are a reliable shower, always rich in activity, although the numbers vary according to how dense the orbiting stream is at the point where we intersect.
The stream is broad too, with the first Perseids appearing in our skies in late July and the final stragglers falling well into the second half of August.
Where to look? The whole sky. The shooting stars will seem to come from the constellation Perseus, in the northeastern sky. But they may appear anywhere as quick streaks of light.
Where not to look? Do not look at the moon or anything bright. Your eyes need to get used to the dark. The full moon will cut down the number of meteors likely to be seen see. By dawn the moon will be low in the western sky so look east.
Where should I go? Anywhere dark with a nice expanse of open sky. Leave the cities if you can.
When to watch? Meteor showers are best after always best after midnight but because of the full moon it’s best to try the hour or two before dawn.