The Perseverance rover is scheduled to take-off on Thursday, July 30 , aboard a United Launch Alliance Atlas V rocket. In addition to a five-jointed robotic arm, aluminum wheels, and a sampling system, the Mars-bound vehicle will also be carrying 23 cameras .

The Mars Descent Imager, or "MARDI," will guide the rover as it lands. Engineering cameras like the Navcam and the Hazcam will help Perseverance to "nav"-igate the planet and avoid "haz"-ardous objects.

These Mars 2020 navigation camera, or Navcam, images show a pile of rocks taken from a distance of about 50 feet in the "Mars Yard" testing area at Jet Propulsion Laboratory in Pasadena, CA. The camera data, shown at right, reveal the contours of a target from a distance. Such measurements give the rover the data required to plan precise travel and arm movements. (Image Credit: mars.nasa.gov)

Science cameras, including Mastcam-Z , SuperCam , PIXL , SHERLOC , WATSON , will support the search for signs of life on Mars. The suite of scientific instruments will use lasers, imagery, and video to find Martian mineral targets to study.

Scooping up soil on a dusty planet like Mars, however, is a dirty job. What happens if the cameras are covered in debris?

In a live Tech Briefs webinar, a reader asked Roger Wiens, lead investigator of the Perseverance SuperCam: "How do you keep the lenses clean?"

Read Wiens's edited response below.

Roger Wiens, Principal Investigator, SuperCAM: That’s a great question. It turns out that the main concern that one would have on Mars is dust. There’s no fogging from moisture. The real issue is whether we bring any contamination from Earth, which we certainly hope we do not.

The other issue is whether we get dust on the lenses or in the mechanisms. Cameras deal with dust in different ways. The cameras that are near the surface of Mars, like WATSON, have a cover. That cover is keeping the lens clean from any blowing dust — except for when it is being used. And so its predecessor MAHLI (the Mars Hand Lens Imager ), which is on the arm of Curiosity, has done very well that way.

The Mars Hand Lens Imager, called MAHLI, acts as a kind of magnifying hand lens for the Mars rover. (Image Credit: mars.nasa.gov)

On the mast, we don’t actually use lens covers. With the mast cameras, there is still some concern for dust, but the cameras are almost two meters up off the ground, so there’s less blowing dust that would hit it. The mast of the rover, however, is tilted down straight down when the rover "sleeps ."

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The rover is almost anthropomorphic. It sleeps with its head down. When the rover is doing anything with the arm that might cause dust, especially drilling and scooping, then the mast actually turns away from the work area. It’s almost like somebody is getting a whole bunch of dust when they’re sanding, and they’re actually turning their face away from what they’re doing so they don’t get dirt in their eyes. That's what we do with the rover.

What do you think? Share your questions and comments below.

Want to learn more about the SuperCam? Listen to our interview with Rogers Wiens.

For more information about the Mars 2020 mission, read our special report: Mars 2020 — Perseverance to the Red Planet.