Why did Psyche slingshot around Mars?

Psyche uses a close Mars flyby to gain speed

NASA’s Psyche spacecraft is set to pass Mars extremely close as part of its route to a distant asteroid named Psyche. The mission design uses the gravity of Mars as a slingshot, boosting the spacecraft’s trajectory without needing additional, large propulsion burns.

Why this matters

Deep-space missions have limited fuel, so planners must “spend” momentum carefully. A gravity assist lets a spacecraft change its speed and direction using planetary motion, helping reach a target that would otherwise require more fuel or a longer, less efficient cruise.

The flyby is also framed as a test of mission operations: approaching a planet closely means the spacecraft must precisely manage navigation, thermal loads, communications, and pointing. That matters because Psyche is traveling to one of the solar system’s most unusual targets—an asteroid that, by its nature and composition, is expected to reveal something fundamentally different about planet formation.

What to watch next

• The spacecraft’s passage time and how closely it comes to Mars.
• Whether navigation and trajectory control remain on plan as the probe transitions from the Mars encounter toward its next phase.
• How engineers interpret performance data collected during the flyby to improve confidence in the long cruise ahead.

Overall, the close approach is a momentum and operations milestone: it’s how NASA turns planetary gravity into the extra reach needed for a mission destined for a scientifically high-value asteroid.