NASA's Perseverance Rover Captures Phobos Transit on Mars

NASA's Perseverance rover captured a solar eclipse on the Martian surface on August 13, 2026. The celestial event occurred just one day after a total solar eclipse was visible from Earth on August 12, marking a rare coincidence of solar alignments across two planets.

Using its Mastcam-Z camera system, positioned high on the rover's mast, Perseverance recorded the Martian moon Phobos as it passed directly in front of the Sun. Unlike the total eclipses experienced on Earth, where the moon can completely obscure the solar disc, this event was a transit. Because Phobos is significantly smaller than Earth's moon, it appears as a dark silhouette moving across the face of the Sun rather than creating a total blackout.

The Nature of Martian Eclipses

Solar eclipses on Mars differ fundamentally from those on Earth due to the size and orbit of the Martian moons, Phobos and Deimos. Neither moon is large enough to fully cover the Sun's disc from the perspective of the surface. Consequently, these events are characterized as transits. Perseverance has captured several of these occurrences since it began its mission in the Jezero Crater in February 2021, providing a consistent record of the Martian sky.

Scientific Significance

These observations are more than mere visual spectacles; they provide critical high-resolution data on the orbital dynamics of Phobos. By tracking the moon's precise path and timing during a transit, scientists can refine their models of how Phobos moves around Mars. Furthermore, these events allow researchers to study the Martian atmosphere by analyzing the behavior of light as it passes through the moon's silhouette, offering insights into the composition and density of the thin Martian air.

Future Observations

As Perseverance continues its exploration of the Jezero Crater, NASA expects to capture further transits. These recurring events will continue to contribute to a broader understanding of the Martian system's gravitational and atmospheric properties. While the August 13 event provided a striking visual parallel to Earth's own solar activity, the long-term value lies in the precise orbital data gathered by the Mastcam-Z system.