Sizzling syzygy

This evening – except for those caught up in a spectacular thunderstorm, who will have their own entertainment – we’ll see the Moon turn to blood just as it heaves its round, full form over the horizon at 8.49pm in London (9.26pm in Glasgow). This is syzygy. Syzygy is a word that generally lives on the Scrabble board. It means a line-up, from an ancient Greek word for “yoking”. The Sun, the Earth and the Moon will be in a straight line. Since the Moon will be in the shadow of the Earth, the only light hitting it will come through the Earth’s atmosphere. Just as delighted shepherds see red skies at night, so the sunset rays penetrating our skin of air will give the Moon a ruddy glow. The end of the show will be after midnight. If it happened every day we’d take it for granted. This one is worth waiting for.