Illustration of the Andromedid, or Bielid, meteor shower of 27th November 1872. Meteor showers, or shooting stars, are dust grains that enter the Earth's atmosphere and glow as they are heated up by air resistance. Although today's Andromedids are very weak (less than three meteors per hour) the shower of 1872 displayed several thousand per hour. The showers occur when the Earth crosses the orbit of debris produced by the comet Biela. Illustration by Fouche.