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NASA Funds 2 Asteroid Missions With Arizona Ties
NASA’s Discovery Program has selected two projects, both with Arizona ties, to delve into the ancient history of the solar system.
One craft, Psyche, will head to the asteroid belt between Mars and Jupiter. The other, Lucy, will explore six asteroids that share an orbit with Jupiter. Scientists believe that the targets embody different aspects of early solar system history.
Led by Lindy Elkins-Tanton, director of Arizona State University’s School of Earth and Space Exploration, Psyche will be the first NASA survey mission run by a team from that university. Following its October 2023 launch and 2030 arrival, the robotic craft will orbit and study 16 Psyche, the solar system’s only known iron-nickel asteroid, for 20 months.
Visiting 16 Psyche could help explain how planets formed, including Earth, where a blend of depth, heat and pressure make study of our core impossible. Not so with 16 Psyche.
“We think that’s the core of an early planet that didn’t survive in our solar system, but instead was battered so that all of the rock fell off the outside of it, and what’s left is the core. So this is the only core that we can ever visit, because we’re never going to visit ours, and there’s no other object like it in the whole solar system.”
Using instruments built by ASU, Applied Physics Laboratory, a consortium between MIT and UCLA and others, the Psyche craft will map the asteroid’s features, structure, composition and magnetic field.
Elkins-Tanton said that no one knows for sure what a metal asteroid will look like. So far, the best image we have shown a mere point of light.
“It’s not going to look like the rocky surface of Mars or the moon. I mean, it’s not going to look like the icy surface of Ceres. It’s going to be something we’ve never seen before," Elkins-Tanton said.
NASA’s other selection, the Lucy mission, is named for the famous australopithecine skeleton that anthropologists consider one of humanity’s earliest ancestors. A team from Southwest Research Institute in Boulder, Colorado, led by principal investigator Harold F. Levison, will run the mission. It is scheduled to depart in 2021.
After a 2025 stop off at a main-belt asteroid, Lucy will spend 2027 to 2033 exploring six of Jupiter’s Trojan asteroids — figurative “fossils” gathered by gravitational forces during the solar system’s early days. Trapped in gravitational dead zones called Lagrangian points, Trojan asteroids lead and follow the gas giant in its orbit.
Lucy will use an ASU-built thermal emission spectrometer to measure asteroid surface temperatures. The university furnished similar instruments to the Mars Global Surveyor and OSIRIS-Rex missions. The latter launched Sept. 8, 2016, to explore the asteroid Bennu — also in hopes of finding clues to our solar system’s past.
Thomas Prettyman, a senior scientist at Tucson’s Planetary Science Institute (PSI), will serve as part of the Psyche mission’s Gamma Ray and Neutron Spectrometer team. Prettyman made news recently when his instrument aboard the Dawn explorer found large amounts of water on Ceres via related methods.
“That instrument is a different technology, but it measures the same types of signatures,” said Prettyman.
PSI also took part in a few runner-up missions, including the Near Earth Object Camera (NEOCam), which would survey potential asteroids threats as they swing through our terrestrial neighborhood. Though NASA did not select the project, the agency did extend its funding for an additional year.
NASA launched the Discovery Program in 1992 as a way to broaden its research through cheaper, faster missions proposed and led by outside teams of scientists and engineers.
Previous winners include: Mars Pathfinder, the first rover to visit the red planet; MESSENGER, Mercury’s first orbital survey mission; and the Kepler space telescope, which has added thousands of exoplanets to our stellar atlas.