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What causes a meteor shower?

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Meteor and meteoroid The Cabin Creek meteorite, an iron (nickel-iron alloy) meteorite that was observed to fall in northwestern Arkansas on March 27, 1886. Its characteristic pattern of “thumbprint” dimples, or regmaglypts, is the result of melting and consequent ablation of its surface as it traveled through the atmosphere. The meteorite is likely a fragment of one of the M class asteroids, which show significant nickel-iron in their surface material.

A meteor shower is a temporary increase in the rate of meteor sightings, occurring when Earth passes through a stream of debris left behind by a comet as it orbits the Sun.1234

As a comet travels near the Sun, solar heating causes its ices to vaporize, releasing dust and larger grains of material. These particles, known as meteoroids, remain in the comet's orbital path, forming a meteor stream. When Earth’s orbit intersects these streams, the meteoroids enter the atmosphere at high velocities. The resulting frictional heating causes the particles to vaporize, creating the luminous streaks of light known as meteors.24356

Because these meteoroids travel in parallel paths within the stream, they appear to originate from a single point in the sky, called the radiant. While most showers are associated with active or defunct comets, some are linked to objects that appear to be asteroids, which researchers often suspect are the remnants of "burned-out" comets.34