Starwatch: a reliable show of shooting stars

The Geminids are one of the most reliable meteor showers of the year, with some 75 bright streaks an hour predicted to be visible from a dark site. They will radiate in all directions from the constellation Gemini, from which the shower takes its name. They are distinguished from other meteor showers in that the bright trails can be multicoloured. Although mostly white, yellow is quite common and green, red and blue have been known. It is thought that the colours come from traces of metals in the dust grains that burn up to produce the meteors. Unlike most meteor showers, which come from comets, the Geminids originate from the asteroid 3200 Phaethon. They are also a comparatively young shower, having first been seen in 1862, and there is some evidence that the shower is getting stronger each year. Meteors from the shower are visible between 4–16 December, but the peak occurs this week on the night of 13-14 December. To see them, wrap up warm and head outside. In the northern hemisphere, any time after dark will be good but in the southern hemisphere, Gemini rises later so aim to start looking around midnight.