Perseverance Captures Earth Vanishing Behind Phobos

NASA’s Perseverance rover has recorded the first observation from the surface of another planet of Earth disappearing behind another celestial object. The rover’s Mastcam-Z camera system captured Earth passing behind the Martian moon Phobos on July 2, 2026, the 1,907th Martian day, or sol, of the mission.

Astronomers call this kind of event an occultation, when a larger-appearing body completely blocks a smaller one from the viewer’s vantage point. The observation was planned and assembled into a composite image by Mark Lemmon, a Mastcam-Z co-investigator at the Space Science Institute in Boulder, Colorado.

What Perseverance saw

The image sequence was taken at about 7 p.m. local solar time, the Martian evening, from the rover’s position on the rim of Jezero Crater. In the composite, Earth travels from the upper left of the frame toward the lower right while Phobos, moving from lower left to upper right, sweeps across its path. In the third frame of the sequence, the two meet and Earth winks out behind the little moon’s shadowed edge.

“The composite image makes for a unique Earth self-portrait, taken from the surface of another planet, with a Phobos photobomb,” said Justin Maki, the Mastcam-Z deputy principal investigator and imaging scientist for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California.

A study in contrasts

From Perseverance’s vantage point, the two objects could hardly look more different. Phobos is a lumpy, potato-shaped moon about 17 miles (27 kilometers) across at its widest point, and it orbits so close to Mars, just 4,850 miles (7,800 kilometers) away, that it appeared roughly one-third the width of Earth’s Moon as seen from our own planet. Earth itself, some 195 million miles (314 million kilometers) away at the time, was reduced to a single, pixel-size dot of light.

“Phobos crosses the Martian sky three times a day, and Earth is visible for months at a stretch, but catching one directly behind the other takes planning and a little luck,” Lemmon said.

Occultations, eclipses, and transits

The Phobos-Earth event is distinct from other sky phenomena Perseverance has documented. An eclipse occurs when one object moves into the shadow cast by another, as when the Moon passes through Earth’s shadow during a lunar eclipse. A transit describes the reverse geometry of an occultation: a smaller-looking object crossing the face of a larger one, such as when Phobos or Deimos crosses the disk of the Sun as seen from Mars, an event sometimes called informally a “Martian solar eclipse.” Perseverance has observed transits before. The July 2 sequence marks the first time an occultation of Earth has been documented from a planetary surface other than our own.

Why the timing mattered

Assembling the sequence required more than luck. Lemmon had to calculate, in advance, exactly when Phobos’s rapid orbit, it circles Mars roughly three times a day, would carry the moon directly across Earth’s position in the Martian sky as seen from Jezero Crater. Mastcam-Z then captured nine separate frames over the several seconds the occultation lasted, which the team stitched into the annotated sequence and a cleaned-up, black-background composite of seven frames showing Earth’s point of light approaching, vanishing, and reappearing at Phobos’s edge.

Who built and operates the mission

NASA’s Jet Propulsion Laboratory in Southern California, managed by Caltech, built Perseverance and operates the rover on behalf of the agency’s Science Mission Directorate as part of the Mars Exploration Program. Arizona State University leads operations of the Mastcam-Z instrument, working with Malin Space Science Systems in San Diego on the design, fabrication, testing, and operation of the camera system. JPL published the observation on August 5, 2026.

Perseverance has spent more than five Martian years studying Jezero Crater’s ancient lakebed and delta deposits, collecting rock cores for eventual return to Earth while also serving as a platform for atmospheric and orbital-mechanics observations like this one. The Earth-Phobos occultation adds little to the rover’s core science return, but it offers a rare, quantifiable data point on the geometry linking Mars, its inner moon, and the home planet, information that mission planners use to refine orbital models for Phobos and to time future imaging campaigns.

Source: NASA, Jet Propulsion Laboratory / Mars 2020 Perseverance mission. Primary source: https://www.jpl.nasa.gov/news/nasas-perseverance-rover-watches-earth-vanish-behind-martian-moon/.