The alpha Monocerotid meteor shower is typically quiet, producing just a few meteors per hour, but a handful of times in the past 100 years, the shower produced hundreds of meteors per hour. Meteor showers occur when Earth passes through the debris field leftover by an asteroid or comet. Don’t be alarmed, the particles from the debris field are only the size of a grain of sand. If the debris field from the comet or asteroid is extremely dense, hundreds or even thousands of meteors per hour will be possible. If this occurs the meteor shower is deemed a meteor storm.