NASA’s mission to a weird metal asteroid has blasted off

NASA’s Psyche mission to a unique, metallic asteroid of the same name launched from Kennedy Space Center’s Launch Complex 39A at 10:20 a.m. Eastern on October 13 via a SpaceX Falcon Heavy rocket.

It was, finally, a smooth exit from Earth for the probe. Psyche had been scheduled to blast off on October 5, the first day of a window that stretches through October 25. But NASA officials announced a delay on September 28, citing issues with the spacecraft’s maneuvering thrusters, which are used to point the vehicle where it needs to go. “The change allows the NASA team to complete verifications of the parameters used to control the Psyche spacecraft’s nitrogen cold gas thrusters,” NASA officials wrote in the announcement. 

That weeklong delay was small, though, compared to the mission’s earlier hold-ups. Psyche was first set to launch in October of 2022, but issues with the navigation software developed by NASA’s Jet Propulsion Laboratory forced the agency to delay the mission by a year. 

This mission should be well worth the wait. It could help uncover details about unusual asteroids and our planet. And the pioneering technology and operations it will demonstrate during its nearly six-year mission will influence the design of future spacecraft. 

Psyche to Psyche

The destination of Psyche (a spacecraft) is 16 Psyche (an asteroid)—an object about 140 miles in diameter in the asteroid belt between Mars and Jupiter. It looks a bit like a cratered potato. 

Remote observations by astronomers have already determined 16 Psyche to be a highly metallic asteroid, rich in iron, and it is believed to be the exposed core of a small planet that never fully formed. Getting up close and personal with 16 Psyche could help scientists better understand Earth’s iron-rich core: It’s easier to send a spacecraft 280 million miles away to study an asteroid than to access Earth’s rocky center, 1,800 miles beneath our feet. Exploring the metallic object in space has implications for our planet’s geomagnetic field, which protects life from space radiation—that field is generated when our planet’s solid inner core spins within liquid metal surroundings. 

Thrusters and lasers

Psyche is one of NASA’s first spacecraft to use solar electric propulsion as its primary means of reaching an asteroid. Rather than relying on traditional chemical rockets, Psyche will use Hall effect thrusters, which use electrostatic fields to accelerate ions—charged particles—and expel them, generating thrust. (These are different machines from the nitrogen thrusters that caused the launch delay.) Such thrusters produce very low thrust—far less than a pound—but do so very efficiently, allowing Psyche to preserve its xenon gas propellant and build up speed over the vast distances it will cover. 

The electric thrusters will use solar power—though the sunlight it absorbs will shrink as Psyche approaches its destination. Still, it’s well prepared. While the spacecraft itself is the size of a large car, its twin solar panels are about the size of tennis courts. They’ll produce 21 kilowatts of energy near Earth and about two kilowatts when at asteroid Psyche. 

[Related on PopSci+: In its visit to Psyche, NASA hopes to glimpse the center of the Earth]

In addition to solar electric propulsion, Psyche will also test a new form of Earth-to-spacecraft transmission system called Deep Space Optical Communication. Deep Space Optical Communication encodes data in infrared lasers, rather than radio waves, and can potentially carry much more information to and from the Psyche spacecraft than can traditional methods. The laser communications are just a demonstration—Psyche will still stay in touch with Earth, and vice versa, using NASA’s radio-based Deep Space Network. 

Research on a metal world

When Psyche arrives at the asteroid 16 Psyche in 2029, it will set to work studying the iron asteroid’s magnetic properties. With the aid of an imager and two kinds of spectrometer, the probe will also use patterns of light absorption to determine what elements and compounds exist on this metal potato. 

But Psyche won’t simply scratch the surface. It will also study the asteroid’s internal structure by measuring the space rock’s gravity field. There’s no specific instrument to pull this off. Instead, scientists on the ground will use radio signals from Psyche to precisely measure the spacecraft’s orbit around the asteroid, measuring any slight perturbations that signal variations in the gravitational field, which in turn can tell scientists about the internal density of 16 Psyche. 

[Related: Smashed asteroid surrounded by a ‘cloud’ of boulders]

And while the Psyche mission has the unique potential to shed light on how planetary bodies are formed and function, it’s also a part of an expanding portfolio of NASA asteroid missions. NASA’s Lucy mission, which launched in 201, is currently on its way to fly by multiple asteroids near Jupiter between 2025 and 2033. NASA’s OSIRIS-REx asteroid sample return mission, meanwhile, just dropped pieces of the asteroid Bennu back on Earth on September 24. It’snow headed to visit the asteroid Apophis; the mission has been renamed to OSIRIS-APEX, or Origins, Spectral Interpretation, Resource Identification, and Security-APophis EXplorer.

Such missions have multiple goals: they help scientists better understand the formation of the early solar system and how planets like Earth, and they can also tell us about the makeup of asteroids that could one day pose a threat—and how to deflect them if necessary. 

Apophis, for instance, was at one time considered a very hazardous asteroid; though it won’t hit Earth, it will pass within 20,000 miles of our planet on April 13, 2029. 

The people of Earth don’t have to worry about any danger from 16 Psyche, though, as it will continue along in its orbit between Mars and Jupiter indefinitely, hundreds of millions of miles from our planet. 

That is, unless humans make changes to the metallic space rock. Mining asteroids is an old idea. But, as spacecraft improve, the estimated $10 quintillion worth of metal ore on Psyche and asteroids like it might begin to look pretty appetizing to companies that want to capitalize on resources in the heavens.

This post has been updated. It was originally published on October 2.