Psyche has a nearly circular orbit in the asteroid belt, so it is unlikely to have come close to Earth.
The metallic asteroid Psyche, shown in this artist's concept, may be the exposed iron-nickel core, or a fragment of one, of a larger object in the early stages of the solar system. But it is probably not associated with the object that created Earth's Moon. Credit: Peter Rubin/NASA/JPL-Caltech/ASU
Could Psyche be the nucleus of the planetesimal body that collided with the Earth and led to the formation of the Moon?
Colton Brooks
Virginia Beach, Virginia
Psyche appears to be an iron core, or part of one, produced during the history of collisions experienced by a fairly large asteroid with other large asteroids. The collision or collisions probably occurred between unusually large bodies, as Psyche is a relatively large asteroid (it was only the sixteenth discovered and, due to its size, can reflect a lot of light), with dimensions of approximately 173 by 144 by 102. miles (278 by 232 by 164 kilometers).
However, there seems little reason to associate it with the likely large collision that formed Earth's Moon, because Psyche has a nearly circular orbit in the asteroid belt, so it is unlikely to have come close to Earth. The object responsible for the collision that formed the Moon is believed to have been one of the largest bodies that formed in the inner region of the Earth-Venus solar system, and that it impacted Earth quite late during our planet's growth.
William Hartman
Senior Scientist Emeritus, Planetary Science Institute, Tucson, Arizona