Perseverance has caught a fabulous solar eclipse on Mars as the funky-shaped moon Phobos passes the Sun. The dramatic footage shows Phobos in all its potato-esque glory as it cuts a speedy swathe across our star.
Rovers on Mars have watched many eclipses by both Phobos and Mars’s other moon, Deimos – but thanks to Percy’s snazzy cameras, NASA says this is the most zoomed-in Phobos eclipse ever snapped from the surface of Mars, at the highest frame-rate yet.
“I knew it was going to be good, but I didn’t expect it to be this amazing,” said Rachel Howson of Malin Space Science Systems in San Diego, one of the Mastcam-Z team members who operates the camera, in a statement.
Taken on April 2, Perseverance's 397th sol, the whole thing only took 40 seconds – much shorter than on Earth, where solar eclipses average 2.5-3 minutes – but then Phobos is 157 times smaller than our Moon (and Deimos is even smaller).
Phobos is just 22.2 kilometers (13.8 miles) across and is unusual for a multitude of reasons. It's the closest orbiting moon in the Solar System, completing an orbit of Mars in just seven hours at a distance of just 9,000 kilometers (5,600 miles). It has one giant crater and a strange chain of craters across its surface, and, along with Deimos, may have been part of a larger moon – or a chunk of the Red Planet itself.
Perseverance's Mastcam-Z camera is the next generation from Curiosity's, having a solar filter and being highly zoomable – perfect for photographing eclipses as the filter acts like sunglasses, reducing the intensity of the sunlight.
“You can see details in the shape of Phobos’ shadow, like ridges and bumps on the moon’s landscape,” said Mark Lemmon, who has orchestrated most of the Phobos observations by Mars rovers. “You can also see sunspots. And it’s cool that you can see this eclipse exactly as the rover saw it from Mars.”
The detail captured will help scientists better understand the moon's orbit and how its gravity affects the interior of Mars. The moon's tidal forces pull on the interior of the planet and its crust and mantle, and each time an eclipse is observed, it helps scientists record the subtle shift in Phobos's orbit over time.
Phobos is actually on a slow path to destruction, set to collide with Mars in tens of millions of years. Recording the subtle shift in Phobos's orbit allows astronomers to refine predictions of when this may be. Until then, it has plenty more mesmerizing eclipses in it, ones that we will hopefully be able to capture in better and better detail.