Psyche Spacecraft’s Mars Flyby: 1,000 mph Boost and Instrument Test

On May 15, 2026, NASA's Psyche spacecraft passed within 2,864 miles of Mars and left the planet with a 1,000 mph boost. Analysis of radio signals between the spacecraft and NASA's Deep Space Network let the flight team confirm that the gravity assist also shifted its orbital plane relative to the Sun by more than 3°. That put the spacecraft almost perfectly on its planned trajectory to reach the metal-rich asteroid Psyche in the summer of 2029.

A calibration opportunity

The close approach let the team power up the imagers, the magnetometer, and the gamma ray and neutron spectrometer. They compared the measurements with surface and atmospheric data from several other Mars missions.

The spectrometer measured neutrons coming from the planet's surface, something it will do at asteroid Psyche to better understand what that body is made of. The magnetometer detected Mars' magnetic field interacting with the Sun's plasma as the spacecraft passed through the planet's bow shock, a trial run for measuring the asteroid's magnetism.

Imaging Mars

The multispectral imager was especially active. Planning relied on a system called Cosmographia, used to simulate the encounter in advance. The team needed to decide how close images had to be taken to overlap enough to build a large mosaic.

The spacecraft also saw Mars from a rare perspective: in a high-phase crescent, only 4% of the planet was illuminated, and the atmosphere could be seen glowing around it. One team member's favorite image looks like an eye. It starts with Mars as a tiny crescent that grows slightly each day until 14 images are stacked, conveying the speed at which the spacecraft travels.

Team members singled out the southern polar cap, Huygens crater and wind-streaked terrain, which they said shows active processes on Mars.

What comes next

With Mars behind it, Psyche will soon resume thrusting with its solar electric propulsion system, heading for the asteroid belt.