Nasa's Psyche spacecraft gets Mars gravity assist on journey to metal-rich asteroid

At a glance:

• NASA's Psyche spacecraft performed a gravity assist flyby of Mars on May 15, 2026, passing within 2,800 miles of the planet's surface
• The maneuver provided a speed boost to the spacecraft, which uses xenon gas propellant and solar-electric ion thruster technology
• Psyche is on a six-year, 2.2-billion-mile journey to explore the metallic asteroid 16 Psyche, with arrival expected in July 2029

What happened

NASA's Psyche spacecraft has successfully completed a critical flyby of Mars, coming closer to the red planet than its own moons. This planned maneuver was designed to utilize Mars' gravitational field to provide a speed boost and adjust the spacecraft's trajectory toward its ultimate destination: the metallic asteroid 16 Psyche. During its closest approach at approximately half past 3 PM Eastern time on May 15, 2026, Psyche passed within just 2,800 miles of Mars while traveling at a speed of 12,300 mph.

The flyby was executed precisely as mission planners had calculated, with the spacecraft using the red planet's gravity to conserve fuel—specifically the xenon gas propellant that powers its innovative solar-electric ion thruster system. This gravity assist maneuver will help Psyche align with its target asteroid's orbit around the sun, setting the stage for the remainder of its multi-year journey. The spacecraft has been approaching Mars since early May and has been capturing images of the planet during its approach, with the planet appearing as a bright, thin crescent from the spacecraft's vantage point.

The mission's scientific goals

Psyche represents one of NASA's most ambitious deep space missions, aiming to unlock the secrets of our solar system's formation by studying a unique metallic asteroid. The spacecraft began its six-year, 2.2-billion-mile journey toward its namesake asteroid in late 2023 and is expected to reach its destination in July 2029. Once there, it will spend approximately two years orbiting the asteroid to conduct comprehensive scientific operations, including taking detailed pictures, mapping the entire surface, and collecting data to determine Psyche's composition.

The scientific community is particularly interested in 16 Psyche because it is the largest known metallic asteroid in our solar system. Scientists theorize that this celestial body could be the exposed iron-rich core of a planetesimal—a solid building block of planets that formed during the early days of our solar system. By studying Psyche up close, researchers hope to gain unprecedented insights into the cores of rocky planets like our own Earth, which we cannot directly observe. "We can't bore a path to Earth's metal core—or the cores of the other rocky planets—so visiting Psyche could provide a one-of-a-kind window into the violent history of collisions and accumulation of matter that created planets like our own," NASA explained.

Why this matters

The successful Mars flyby represents a crucial milestone in the Psyche mission, demonstrating the effectiveness of gravity assist maneuvers for deep space exploration. These techniques allow spacecraft to achieve the necessary velocity and trajectory adjustments without carrying excessive amounts of fuel, which would otherwise make missions prohibitively expensive and technically challenging. Psyche's use of xenon gas propellant with solar-electric ion thruster technology represents a cutting-edge approach to propulsion that could influence future interplanetary missions.

The mission's significance extends beyond technological achievements, offering potential insights into planetary formation processes that have shaped our solar system. By examining what may be a primordial planetary core, scientists hope to understand how terrestrial planets like Earth, Mars, and Venus formed and evolved. This knowledge could also inform our understanding of exoplanets and the potential for metal-rich worlds elsewhere in the universe. As Psyche continues its journey, the images and data it gathers during the Mars flyby will be transmitted back to Earth via NASA's Deep Space Network antennas, with mission updates and findings being shared through the official Psyche mission webpage.