NASA’s Perseverance Rover Spots Phobos Crossing the Sun
Sci.News · 2026-08-24
NASA's Perseverance rover recently captured a transit video of Phobos, one of Mars's moons, sweeping across the Sun from Jezero crater. The rover's Mastcam-Z camera recorded the event on August 12, 2026, the 1,948th Martian day of its mission. Phobos, discovered on August 17, 1877, is the larger and innermost of Mars's two moons, measuring approximately 26 x 22 x 18 km (16.2 x 13.7 x 11.2 miles) with a distinctively lumpy appearance. It orbits Mars at just 6,000 km (3,700 miles) from the surface, completing an orbit in a mere 7 hours and 39 minutes, which is about three times faster than Mars's rotation. This unique orbital characteristic causes Phobos to rise in the west and set in the east from the Martian surface. Unlike Earth’s Moon, Phobos is too small and close to fully block the Sun, resulting in a partial transit rather than a full eclipse. Scientists are using these recordings to refine their understanding of the moon's changing orbit, noting that Phobos is expected to eventually spiral toward the Red Planet's surface in the distant future.
*The full article also explores the visual simulation of the transit for a human observer on Mars.*