Researchers from across the country, including at Yale, are currently working with NASA to send a spacecraft to an entirely metal asteroid.
The launch of the spacecraft Psyche should take place around 2023 and will reach the asteroid around 2030. The asteroid, named 16 Psyche, is believed to be made almost entirely of nickel and iron alloy that scientists predict could be the frozen core of an early planet. The researchers hope to learn through investigating Psyche about the core of other planets, including Earth’s, and about planet formation and collisions.
“Humankind has never seen a metal world before,” said Linda Elkins-Tanton, a professor at the School of Earth and Space Exploration at Arizona State University and the mission’s principal investigator. “We’ve been to places made of rock and ice and gas but never metal. And it turns out there is just this one fairly large, fairly spherical metal body in our whole solar system.”
Elkins-Tanton hypothesized that this asteroid could actually be the remnants of an early dwarf planet whose rocky exterior was knocked off during a collision with another planet, leaving behind a metal core. If this hypothesis turns out to be true, Psyche could be a great opportunity to learn about the core of other space bodies, such as Earth or the moon, she said.
The researchers plan to look at what the core is really made of, whether or not it has a magnetic field and if there are patches of rock left over on the surface from the original mantle — the layer of the planet surrounding the core. They hope to use this information to learn more about the formation of planets in general.
“We’ll learn about what’s inside planets today and we’ll learn about how they were formed back in the early solar system,” Elkins-Tanton said. “Or maybe we’ll discover that it’s not a planetary core, that it’s maybe something even more exciting.”
David Bercovici, a Geology and Geophysics professor at Yale and a co-investigator for the project, said he is excited to look at Psyche’s shape and magnetic field in order to learn more about how cores will evolve after losing their mantles.
The shape and makeup of the asteroid will give researchers information about what happens when a core freezes. Bercovici hopes to figure out whether the core “flash froze” and how much of the magnetic field was locked into the metal alloy.
“While it was freezing and cooling, [Psyche] might have generated its own magnetic field, and that’s something we’d like to see,” Bercovici said.
Bercovici added he hopes to look at the impact of collisions on planets. He is among the researchers who predict that the mantle was blown off during a collision with another planet. The gravity of the core was then probably unable to attract the mantle back to the original planet, and once exposed, the core froze, Bercovici said.
While the researchers are currently just making predictions, the next 13 years leading up to the arrival at Psyche will be filled with preparations for analyzing the data to be sent back by the spacecraft.
“I think that space exploration actually has a much bigger purpose than just understanding the science,” said Elkins-Tanton. “Really, it’s for inspiration. It’s to make people think that they could do something bigger; they could do something bolder. They don’t have to be tied up with the frustrations and the frictions of the everyday because they could be looking outward toward bigger goals.”
Psyche is part of NASA’s Discovery Program, a national competition in which scientists propose missions to NASA in order to test a scientific hypothesis.