NASA's Psyche Spacecraft Heads to Cape Canaveral

In 2011, Lindy Elkins-Tanton and a couple of colleagues wrote a paper exploring ideas about how tiny would-be planets called planetesimals might have formed billions of years ago, and speculated about whether their remnants might still orbit in the asteroid belt. Afterward, officials at NASA’s Jet Propulsion Laboratory in Pasadena, California, approached her. “Would you like to propose a mission to test your hypothesis?” they asked. “My response was, ‘What?’ because it had never occurred to me to do that,” she says. But 11 years later, her work has led to a new asteroid-bound spacecraft that is headed to the launchpad.

Elkins-Tanton, a planetary scientist at Arizona State University in Phoenix, now leads NASA’s new Psyche mission—named after both the probe and the asteroid, which was itself named after the Greek goddess of the soul. The probe will visit the asteroid to study what it’s made of and figure out how it formed, looking for clues about how the solar system’s rocky planets themselves may have assembled. Engineers finished up their tests on the Psyche spacecraft at JPL this week and are shipping it by truck and plane to Cape Canaveral, Florida, where it will arrive on Friday. There, the team will fit it and its solar panels atop a SpaceX Falcon Heavy rocket and prepare it for launch, scheduled for August 1.

Building operations for the craft have been underway for over a year in the High Bay 1 clean room within JPL’s Spacecraft Assembly Facility, where Elkins-Tanton and her team have been tweaking and testing its instruments, including subjecting the spacecraft to rigorous electromagnetic, thermal-vacuum, vibration, shock, and acoustic testing to make sure it can withstand the vigorous shaking involved in the launch. The room is designed to ensure no dust or fingerprints disturb the functioning of the sensitive instruments and that no contaminants from Earth end up being transported to other worlds. Just to enter the room, one has to don a sterile “bunny suit,” which includes hair and shoe coverings, a smock, and gloves, then walk across sticky floor mats that trap loose dirt and through a phone booth-sized room with air jets that blow away any additional particles that might be hiding on clothing.

The probe is boxy, and about the size of a car, topped by a big saucer-shaped high-gain antenna, which will be used to send and receive signals from home. When WIRED visited the clean room in April, those tests were still in progress. A handful of stanchions and a sign that read “Psyche: Journey to a Metal World” kept visitors at a distance from the black and gray craft, where a technician was working on a tube-like transceiver on the bottom. Holes could be seen along the sides, where two arrays—each made of four solar panels—will later be attached. Most of Psyche will be flown within an environmentally controlled container on a direct flight to Cape Canaveral aboard a bulbous C-17 transport aircraft, but these sets of solar panels will be shipped separately and will rejoin the spacecraft closer to launch.

Psyche, the asteroid, makes a unique target. It’s a 140-mile-wide, potato-shaped object mostly made of metals, rather than rock and ice, circling the sun between the orbits of Mars and Jupiter. “It’s the largest metallic asteroid in the solar system. It’s been studied extensively from Earth, but we don’t know how it was born and evolved to its current state,” says Juan Sanchez, an astronomer at the Planetary Science Institute in Tucson, Arizona, who researches Psyche but is not involved in the mission.

That composition means Psyche might not simply be a world with a unique combination of metals—it might be part of the core of a baby planet, left behind after massive impacts with other asteroids smashed up its outer layers during the solar system’s tumultuous early eons. In fact, if Psyche is a planetesimal’s core, it might resemble the metallic innards of the rocky planets that exist today. “It would be cool to see a core. We can’t go to Earth’s core—outside science fiction—so this is our chance to study what is inside these objects,” says Vishnu Reddy, an astronomer at the University of Arizona in Tucson who has worked with other asteroid missions, but not Psyche.

Elkins-Tanton is pretty sure Psyche is made up of an alloy of metals like iron and nickel, the same elements found in the cores of the inner planets, including Earth. It also likely holds tiny amounts of copper, and more lucrative metals like platinum, that might one day interest space mining companies.

The plan is to steer the Psyche craft into orbit around the asteroid in January 2026 and keep it there for at least 21 months, letting it map the object, snap photos, and probe its inner structure remotely. While orbiting, the spacecraft will employ its magnetometer, developed by scientists at the Technical University of Denmark and MIT, to measure whether the asteroid retains a relic magnetic field, which would count as evidence of it being a baby planet’s core. The craft also comes with imagers made by the San Diego-based company Malin Space Science Systems. Pictures taken by the spacecraft will be piped down to Earth via the Deep Space Network, an international system of giant antennas managed by JPL. Because of the distance between Earth and the asteroid belt, they won’t arrive in real time, but they’ll be released to the public within 30 minutes of their arrival. “We’re not going to edit them. We’re not going to censor them. Everyone in the world can be looking at them and wondering what they are at the same time because space missions are for everyone,” Elkins-Tanton says.

The spacecraft also comes with a gamma-ray and neutron detection instrument made at the Johns Hopkins University Applied Physics Laboratory. That will allow scientists to determine how much iron, nickel, and other elements can be seen on the asteroid’s surface. Finally, the radio telecom system can also be used to make gravity measurements. Since metal is twice as dense as rock, those can be used to determine whether Psyche is indeed a mostly metal world or there’s more rock mixed in than previously thought.

For the body of the Psyche spacecraft, on which all the instruments are mounted, NASA partnered with Maxar Technologies, based in Westminster, Colorado, marking the company’s first time working on a deep space mission and reducing costs by adapting an off-the-shelf communication satellite chassis. The company also built the big, cross-shaped solar arrays, which, when unfurled in space, will make the spacecraft extend the length of a tennis court. While those solar panels will collect 20 kilowatts of energy from the sun near the Earth, that will drop to around 2 kilowatts when the spacecraft reaches Psyche.

The spacecraft also includes a technology demonstration of something called Deep Space Optical Communications (DSOC). While all deep-space missions past the moon, including Psyche, rely on radio waves to communicate, it’s possible to encode more information with lasers—a first step toward improving communications for future missions to Mars, and even enabling video streaming.

Psyche is the latest in a series of close-up comet and asteroid investigators tasked with expanding our understanding of the materials that helped form the solar system. The European Space Agency’s Rosetta spacecraft flew by the metallic asteroid Lutetia before its lander successfully alighted on a comet in 2014, but Psyche will be the object of more focused study. NASA’s Dawn spacecraft traveled to Vesta, the largest asteroid in the solar system, and the dwarf planet Ceres in the asteroid belt in 2015, while Japan’s Hayabusa2 and NASA’s OSIRIS-REx visited carbon-dominated near-Earth asteroids Ryugu and Bennu in 2018 and took samples of each. (The former has already delivered a sample back to Earth.) Last year NASA also launched Lucy, a probe that will fly by the Trojan asteroids, which are gravitationally trapped in the same orbit around the sun as Jupiter.

But for now, NASA’s main task is getting Psyche to Florida and then unpacking it and readying it for launch. Once Psyche arrives at Cape Canaveral, the team will work for three months setting up ground support equipment, running tests to make sure everything shipped properly, and finalizing the hardware, says Henry Stone, the Psyche program manager at JPL. They will also test the telecom system for sending commands and receiving data via the Deep Space Network. With so much work culminating at once, Stone says he is both excited and anxious. “This is the point of the project where all the nerves are coming,” he says.

Elkins-Tanton feels they’ve tested everything they can in a clean room—now the real test will happen in space. “I’ve spent years feeling nervous about the instruments, and now I’m really confident about them,” she says. “I’m not even very worried about the launch. I’m more worried about surprises we don’t anticipate. It’s a very complicated system.”

NASA's Psyche Spacecraft Heads to Cape Canaveral

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