Dark skies help us see the starlight

HALLOWE’EN is almost here, a time when long nights and more hours of darkness are ushered in. But, in a world that has become obsessed with light, there are many urban areas where darkness scarcely exists any more and the sight of star-speckled skies is a rarity.

Satellite photographs of Ireland and neighbouring countries at night show that while we still have some of the darkest skies left in Europe, especially along the western seaboard, the situation is changing.

Just consider Dublin and the 47,000 lights it takes to illuminate the city. About 30% of that light is unnecessary and creates “sky glow”, experts say. In Cork, Galway, Dublin and Belfast, it’s harder than ever to spend the night stargazing.