Phaethon
3200 Phaethon is a near-Earth asteroid that is the parent of the Geminid meteor shower.
3200 Phaethon is a near-Earth asteroid about 5 to 6 kilometres across, discovered in 1983 by the Infrared Astronomical Satellite. It was the first asteroid found by a spacecraft. It is named after the son of the Sun god Helios in Greek myth, who drove his father's chariot too close to the Earth.
Phaethon has an unusual orbit that takes it closer to the Sun than Mercury, to about 0.14 astronomical units. Soon after discovery, astronomers noticed its orbit matched that of the Geminid meteor shower, which peaks around 14 December. This made Phaethon the first asteroid linked to a major meteor shower.
Most showers come from comets, so how Phaethon produces so much debris is a puzzle. It may be a dead comet, or its surface may crack and shed dust when scorched near the Sun. Japan's DESTINY+ mission is planned to fly past it later this decade.
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