Psyche (16 Psyche) is the sixteenth asteroid discovered,
discovered in 1852, which is about the time that astronomers began
to consider asteroids to be something other than regular planets.
It lies in the main asteroid belt, roughly between the orbits of
Mars and Jupiter.
Both its albedo characteristics and mass determinations
through perturbation observations suggest it includes iron
and nickel, its bulk density somewhat greater than that of rock.
Characteristics:
3.8 × 10-6Earth masses (2.29 × 1019 kg or 0.0003 Moon masses).