Metis is the innermost known moon of Jupiter, orbiting within the planet’s main ring system. It has a very short orbital period, completing a full orbit in just about 7 hours. Because it is so close to Jupiter, Metis is tidally locked, meaning the same side of the moon always faces the planet. Its long axis points toward Jupiter, a result of the intense gravitational forces at play.

Metis, along with the nearby moon Adrastea, is believed to contribute material to Jupiter’s main ring. Micrometeoroid impacts on their surfaces eject dust and debris, which then become part of the ring. These moons are crucial in maintaining the structure and visibility of the faint ring system.

Due to its close orbit, tidal forces are gradually pulling Metis inward. Its orbit is decaying, increasing the likelihood that it will eventually spiral into Jupiter and be destroyed. This slow inward drift is a result of gravitational interactions between the moon and the planet’s strong tidal field.

Metis was discovered in 1979 by Stephen P. Synnott using images captured by the Voyager 1 spacecraft. It remains a key object of interest in studies of planetary rings and close-orbiting moons.