The Perseverance Mars rover captured a very unusual sight without analogs on our Earth: an “eye” that seems to be looking at the Red Planet from space.
In fact, Perseverance photographed an eclipse caused by the passage of Mars’ largest moon, Phobos, across the solar disk. It took place on September 30, 2024, on the 1285th sol of the Perseverance mission. Solar eclipses on Mars look very different from those on Earth. The orbit of Phobos passes at a distance of only 6,000 km from the planet’s surface. For comparison, the average distance between the Earth and the Moon is 384,000 km.
But the point is that Phobos is a very small celestial body. It resembles a potato in shape, at its widest point its cross-section is only 27 km (the Moon’s diameter is 3,474 km). Therefore, Phobos can only cover up to half of the solar disk.
Another important difference between Earth and Martian eclipses is that Phobos’ orbit coincides almost perfectly with the Martian equator. Therefore, its passages across the Sun’s disk can be observed during most days of the Martian year. But as Phobos moves very fast (the moon needs only 7.6 hours to complete a full orbit around Mars), its transit usually lasts about 30 seconds.
It is worth noting that this is not the first time that NASA’s rover has managed to see a solar eclipse. Since landing in the Jezero crater in February 2021, Perseverance has captured several transits of Phobos. Curiosity made the video in 2019. And Opportunity took the photo back in 2004.
Provided by NASA
