Illustration of NASA's Psyche mission near its target, the asteroid 16 Psyche. This asteroid has a diameter of over 200 kilometres and is one of the largest asteroids in the asteroid belt between Mars and Jupiter. The spacecraft has a distinctive five-panel solar array, as well as power and propulsion systems to travel to, and orbit, the asteroid. The mission plans to launch in October 2023 and arrive at Psyche in 2029. This asteroid is made almost entirely of nickel-iron metal. It should provide evidence about the initial conditions in which Earth and the other rocky planets formed.