ASU scientist and Mastcam-Z leader Jim Bell discusses the rover's latest surprising discoveries
You’re on vacation, driving around on the Red Planet. What catches your eye? What’s worthy of a photo?
NASA’s Mars 2020 Perseverance rover has snapped over 200,000 images since it landed on Mars in February 2021. The rover is equipped with 23 cameras, and two of the largest and most capable are the Mastcam-Z cameras.
Arizona State University Professor Jim Bell is NASA’s principal investigator for Mastcam-Z. Its two cameras are inside the box that looks like a rectangular crow’s nest atop the rover’s pivoting mast.
Learning by looking
Perseverance has now traveled more than 8 miles on Mars. Like any good adventure, it has served up some surprises.
Its Jezero Crater landing site was chosen because it’s on an ancient lake bed — the kind of place where you would expect to find lake bed sediments.
“And what we found is a lot of textures that match what we see when we go look at volcanic terrains on the Earth, lava flows or places where lava has come out of the ground or been erupted,” Bell says. “We see, for example, textures that look like pahoehoe lava flows on the island of Hawaii or Iceland. We see places where it looks like the flows have banded around obstacles and swerved almost in a fluid-dynamic kind of way.”
Bell is a planetary scientist who teaches in the School of Earth and Space Exploration.
“And this was cool to geologists to see volcanic kinds of features,” Bell says. “Most of us were expecting to see lake bed sediments, and they're probably there, maybe buried under these volcanic rocks. Maybe the volcanic rocks came later. We know that there's lake sediments there because there's a giant delta right next to us that we've also taken spectacular images of. But still, you know, a bit surprising to not get exactly what we're expecting to see.”
Video by Stephen Filmer
Pictures pick what’s worth bringing back
One goal for Perseverance is to look for possible signs of past life on Mars. To do that, scientists need to look close.
Mastcam-Z has two cameras, which can zoom in and out and be used to create three-dimensional stereo images. This is a first for cameras on Mars, and it is a significant help in understanding rocks, dust and other geological and meteorological features on the surface.
One of the most important roles for the Mastcam-Z team is to create images that help NASA make choices about which core samples will be worth bringing back to Earth.
“We know that some of the samples we'll be bringing back are likely volcanic rocks, which means we can take them into laboratories like the labs here in SESE and do absolute age dating and other, all kinds of detailed geochemistry on them,” Bell says. “So, unexpected, but exciting results.”
Those samples are part of Mars Sample Return (MSR), which will involve a separate lander-and-launcher to bring them to Earth. School of Earth and Space Director Meenakshi Wadhwa is the program scientist for MSR. NASA and the European Space Agency are planning technology that is expected to collect and transport the samples in the early 2030s.
To get ready for sample return, Mastcam-Z’s next role will be helping locate and create a contingency sample site.
“Sometime in the next month or so, we will take roughly half of the samples that we've collected so far and place them in a pretty boring flat area right in front of the delta,” Bell says.
This site is a "just-in-case" backup plan by NASA, in the event the rover doesn’t survive as long as hoped.
“And they'll be there for the sample return lander and the fetch helicopters that land to pick up and put into the rocket, which will go into Mars orbit, catch up with the orbiter and bring back to the Earth,” Bell says.
After that, it’s on the road again for Mastcam-Z. The 2023 travel calendar for Perseverance is to drive to the top of the delta above Jezero Crater. Expect the spectacular — and maybe a few new surprises.
An earlier version of this story had an incorrect month for the Perseverance rover's landing. It launched in July 2020 and landed in February 2021.
Top image: NASA’s Perseverance Mars rover took this selfie over a rock nicknamed "Rochette" on Sept. 10, 2021. Photo by NASA/JPL-Caltech/MSSS