More than two centuries after asteroid 16 Psyche was first identified, scientists are still trying to determine how it formed.

Located in the main asteroid belt between Mars and Jupiter, Psyche ranks as the 10th-most massive asteroid and the largest known object made primarily of metal, measuring about 140 miles across. NASA's Psyche spacecraft is scheduled to arrive in 2029 with the goal of uncovering its origin. Researchers suspect it could be a remnant of an early planet that was torn apart by massive collisions, or possibly a fragment of a once-layered body that lost its outer rocky shell.

Other ideas suggest Psyche may have formed as a metal-rich object from the start, or that it became a mix of rock and metal after repeated impacts with other asteroids. Each possibility points to a different story about how planets formed in the early Solar System.

>Simulating Craters to Reveal Psyche's Interior>

To explore these possibilities, scientists at the University of Arizona's Lunar and Planetary Laboratory created simulations to understand how a large crater near Psyche's north pole may have formed. Their findings, published in JGR Planets, provide predictions that will help researchers interpret data collected by NASA's Psyche mission when it arrives. By combining these simulations with real observations, scientists hope to finally determine what Psyche is made of.

"Large impact basins or craters excavate deep into the asteroid, which gives clues about what its interior is made of," said Namya Baijal, a doctoral candidate at the LPL and first author of the paper. "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."

Although metal-rich asteroids make up less than 10% of the main belt, Psyche is the largest among them. Still, researchers will need direct spacecraft measurements to understand how that metal is distributed throughout its interior.