NASA will send a spacecraft to main-belt asteroid Psyche, a so-called metal world that scientists believe is made almost entirely of iron and nickel. The Psyche spacecraft is set for launch in summer of 2022 with arrival planned at the asteroid in 2026. Travel will require the use of solar electric propulsion, which uses electricity generated from solar arrays to ionize atoms of the propellant xenon. These ions are then expelled by a strong electric field out the back of the spacecraft to produce thrust.

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