Craters Reveal Asteroid 16 Psyche's Origins

Simulations help predict what NASA's Psyche mission may find when it arrives in 2029.

Mar. 17, 2026 at 8:24am

Got story updates? Submit your updates here. ›

Even 200 years after asteroid 16 Psyche was discovered, astronomers continue to puzzle over its formation. Psyche is the 10th-most massive asteroid in the main belt between Mars and Jupiter, and the largest known metallic asteroid, at 140 miles in diameter. NASA's Psyche mission will arrive in 2029 to determine its origin. Researchers at the University of Arizona's Lunar and Planetary Laboratory ran simulations to predict how a large crater near Psyche's north pole could have formed under different hypotheses about its composition, in order to help interpret the data the mission will collect.

Why it matters

Psyche may be a leftover building block of an early planet, shredded by violent collisions, or a planetary fragment that once separated into layers before losing its rocky outer mantle. Understanding Psyche's origins could provide insights into the early formation of planets in our solar system.

The details

The researchers used the best shape model of Psyche, derived from telescope observations, to create a 3D target. They reproduced the formation of a specific concavity in the model, about 30 miles across by three miles deep, as a simulated impact in which Psyche was hit at speeds typical of asteroid belt collisions – about three miles per second. The team varied the size of the virtual impactors and tested two models of Psyche's interior structure: a layered structure with a metallic core and a thin, rocky mantle, and a uniform mixture of metal and silicate. They found that an impactor about three miles across would create a crater of the right dimensions, and the crater's formation is consistent with both scenarios of Psyche's makeup.

  • Psyche was discovered over 200 years ago.
  • NASA's Psyche mission will arrive at the asteroid in 2029.

The players

Namya Baijal

A doctoral candidate at the University of Arizona's Lunar and Planetary Laboratory and first author of the study.

Erik Asphaug

A professor at the University of Arizona's Lunar and Planetary Laboratory and co-author of the study.

Adeene Denton

A postdoctoral researcher and co-author of the study.

Lindy Elkins-Tanton

The principal investigator of the Psyche mission at the University of California, Berkeley.

NASA's Jet Propulsion Laboratory

The division of Caltech in Pasadena, California, responsible for the Psyche mission's overall management, system engineering, integration and test, and mission operations.

Got photos? Submit your photos here. ›

What they’re saying

“Large impact basins or craters excavate deep into the asteroid, which gives clues about what its interior is made of. By simulating the formation of one of its largest craters, we were able to make testable predictions for Psyche's overall composition when the spacecraft arrives.”

— Namya Baijal, doctoral candidate (JGR Planets)

“One of our main findings was that the porosity – the amount of empty space inside the asteroid – plays a significant role in how these craters form. Porosity is often ignored because it's difficult to include in models, but our simulations show it can strongly affect the impact process and shape of craters left behind.”

— Namya Baijal, doctoral candidate (JGR Planets)

“By rigorously treating Psyche's shape, porosity and composition, this work represents a true watershed moment for our capacity to realistically simulate impacts into unique types of asteroids.”

— Adeene Denton, postdoctoral researcher (JGR Planets)

What’s next

When the Psyche spacecraft arrives at the asteroid in 2029, scientists will be able to compare the observed crater shapes and other features with the predictions from these simulations in order to determine the asteroid's internal structure and composition.

The takeaway

Understanding the origins of the metallic asteroid Psyche could provide valuable insights into the early formation of planets in our solar system. The simulations conducted by researchers at the University of Arizona will help guide the interpretation of data collected by NASA's Psyche mission, which is scheduled to arrive at the asteroid in 2029.