NASA’s Psyche spacecraft successfully completed a gravity-assist maneuver at Mars on May 15, 2026, using the planet’s gravitational pull to gain a 1,000-mph boost in speed and tilt its trajectory toward its 2029 asteroid target. The flyby, which brought the probe within 2,864 miles (4,609 kilometers) of the surface, allowed engineers to calibrate scientific instruments and capture a rare timelapse of the Red Planet as it swelled from a crescent into a cratered world.
Mars Flyby Mechanics and Trajectory Adjustments
The encounter served as a critical navigational milestone for the mission, which launched in October 2023. By passing close to Mars, the spacecraft adjusted its flight path, a maneuver necessary to reach the metal-rich asteroid 16 Psyche, located in the main asteroid belt between Mars and Jupiter. The mission is scheduled to reach its destination in the summer of 2029.
This gravity assist was years in the making, and the navigation team nailed it — Psyche flew by Mars on exactly the trajectory we needed to set us on a path to rendezvous with the asteroid in the summer of 2029,
said Bob Mase, Psyche’s project manager at NASA’s Jet Propulsion Laboratory in California.
While reports vary slightly on the exact proximity, the maneuver brought the spacecraft within the range of 2,864 miles (4,609 kilometers) to 3,500 kilometers of the planet, providing a unique opportunity for instrument calibration against a well-studied body.
Instrument Calibration and Scientific Data Collection
Mission teams utilized the encounter to test the spacecraft’s scientific payload, ensuring all systems are prepared for the 2029 arrival. The suite of instruments—including the multispectral cameras, magnetometer, and gamma-ray and neutron spectrometer—operated under dynamic conditions during the flyby, with all three performing as expected.
The mission’s magnetometer, which will search for evidence that asteroid Psyche is the metallic core of an early planetesimal, recorded its first magnetic signature from a planetary body since the 2023 launch. Ben Weiss, Psyche’s deputy principal investigator and the magnetometry investigation lead at MIT, stated that the instrument detected an intense uptick in the magnetic field corresponding to the bow shock region, where the solar wind slams into Mars’ magnetic environment. The magnetometer utilizes a gradiometer system—a pair of sensors mounted on a 2.15-meter boom—which allows the team to separate the spacecraft’s own small magnetic field from that of its target.
Additionally, the mission’s twin multispectral cameras passed calibration tests, capturing frames for the time-lapse while spotting Mars’ tiny moons, Phobos and Deimos. Spotting the moons served as a practice for the satellite search that we'll use at the asteroid Psyche to look for any moonlets there,
said Jim Bell, a planetary scientist at Arizona State University who leads the multispectral imager instrument team.
The gamma-ray and neutron spectrometer, designed to determine the asteroid’s elemental makeup, also confirmed its operational readiness by detecting the predicted surge of escaping neutrons during the closest approach.
Visualizing the Encounter: The NASA Timelapse
NASA released a new timelapse video, stitched together from images taken throughout May, documenting the probe’s transition as it approached and departed the planet. Hannah Zigo, a Psyche team member at Arizona State University, explained that the spacecraft approached from a “high phase” angle relative to the sun. This perspective initially captured Mars as a slender crescent with only 4 percent of its disk illuminated, with the planet’s thin atmosphere glowing in scattered sunlight. As the spacecraft closed in, the video revealed the ancient double-ringed Huygens crater and the south polar ice cap.
Despite the high quality of the imagery, researchers emphasized that the flyby was not intended for new planetary discovery. We didn’t anticipate big discoveries, given how extensively the planet has been studied,
said Lindy Elkins-Tanton, the mission’s principal investigator at the University of California, Berkeley. But we did complement Mars science with the data we collected through Psyche’s unique perspective.
Status of the Solar-Electric Propulsion System
With the Mars encounter complete and instruments fully vetted, the spacecraft remains locked on course. Mission managers report that the hardware is in great shape as it continues its journey through the solar system. The spacecraft is in great shape, and we're on schedule to resume sustained thrusting with the solar-electric propulsion system later this fall,
Mase said.
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