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Why does Earth experience the Eta Aquarid meteor shower each May?
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Small body
Asteroid Ida and its satellite, Dactyl, photographed by the Galileo spacecraft on August 28, 1993, from a distance of about 10,870 km (6,750 miles). Ida is about 56 km (35 miles) long and shows the irregular shape and impact craters characteristic of many asteroids. The Galileo image revealed that Ida is accompanied by a tiny companion about 1.5 km (1 mile) wide, the first proof that some asteroids have natural satellites.
Earth experiences the Eta Aquarid meteor shower each May because it passes through a stream of debris left behind by Halley’s Comet.21
As Halley’s Comet travels near the Sun, it is heated, causing its volatile ices to vaporize and release dust and larger grains along its orbit. This debris forms a meteor stream that Earth intersects annually. When Earth moves through this stream, the particles enter the atmosphere and burn up, creating the meteor shower observed from the ground. The Eta Aquarids are specifically associated with the debris shed from Halley’s Comet over millennia of the comet's disintegration.2341