Scientists are mapping out a mission to the metallic asteroid Psyche, which is thought to be the exposed iron core of a protoplanet. The proposed mission would reveal insights about planet formation and afford the first-ever good look at a metal world.
Discovered in 1852, the main-belt asteroid Psyche is unique in that it is believed to be the exposed core of an ancient protoplanet that never completely formed, or whose rocky outer layers were destroyed. It is the most massive known M-type (metallic) asteroid, with a composition of 90-percent iron and nickel, and 10-percent silicate rock — similar to Earth's core.
The Earth's nickel-iron core is a dynamo that creates a massive magnetic field around the planet. Scientists believe Psyche also generates a magnetic field, perhaps nearly as strong as that of Earth.
Psyche is an irregularly-shaped asteroid measuring about 150 miles (240 kilometers) along its largest side. This makes it the 10th or 11th largest known asteroid (sizes are not known precisely, preventing exact rankings). The largest asteroids, including Ceres and Vesta, are protoplanets – survivors from the early formation of the solar system.