When you’re out trick-or-treating this Halloween, keep an eye on the sky for an unusual cosmic treat – brilliant shooting stars called fireballs. They may represent the afterlife of a huge comet that died 20,000 years ago.
Every year, we experience regular showers of shooting stars, when the Earth ploughs into trails of dust shed by comets as they tramp around the solar system. This month, for instance, we’ll enjoy a display of Orionid meteors on the night of 21 October: these are fragments littering the orbit of Halley’s comet, that burn up in the Earth’s atmosphere way over our heads and seem to stream outwards from the constellation Orion.
