If you’ve been following our news on Martian exploration, you’ll know that scientists are waiting for the day they’ll be able to exclaim “Eureka! There’s life on this dead, floating space rock!” Luckily, a 2,260-pound robot geologist, living in Mars’ Jezero Crater, named Perseverance (or affectionally, “Percy,” for short), is helping them get a bit closer to this goal. 

One of Perseverance’s goals has been to aid in humankind’s search for ancient life on the red planet. Unlike its preceding rover siblings, Percy’s superpower lies in its capability to store samples of rocks that geologists deem interesting enough for it to cache for possible return to Earth. This is very similar to how Wall-E collects trash in his robot tummy; however, Percy doesn’t crush and compact the materials inside (that would lead to some pretty angry scientists, we imagine). 

The rocks that are captured may be retrieved by a future mission, then transported to Earth for detailed study. Perseverance has a whole suite of high-tech equipment on board, including sensors and tools that allow for analytical investigations of rocks on the go, informing decisions regarding sample acquisition. 

Would you like to imagine what the sample gathering will be like? Check out this animation and get excited about it with us. 

When asked of the importance of Martian roving missions, Dr. Ken Herkenhoff, scientist emeritus, highlighted the sample return’s prominence in the mind of scientists. “Returning samples from Mars has long been a goal of the planetary science community,” he mused. An expert on the subject, Dr. Herkenhoff has been in the planetary science realm for more than 25 years, playing a part in too many critical missions over the years to name- and was most recently a member of the team that chose which of Percy’s samples would be saved for the return mission to Earth. 

What is Percy really looking for in these rocks though, and how did scientists like Dr. Herkenhoff determine where to look for samples? Potential biosignatures, or markers of life, such as specific ions, elements, and isotopes, are the most critical information scientists can glean from the rocks Percy observes. While we won’t drone on about the chemistry involved, just know that if a biosignature is found both on another planet and on the Earth, it’s a large indicator that life as we know it may have existed (or still does) in some capacity on that planet. For example, this is why the existence of water on other planets is such a big deal to planetary scientists- it suggests that perhaps the rivers, lakes, or seas on those planets harbored microbial life, much like they currently do on earth. 

Jezero Crater, the place where Perseverance was sent to explore, is an area that could potentially be rich for finding biosignatures, as it was believed to have been a river delta back in its heyday (a cool 3.5 billion years ago), flowing into the now-dry Lake Jezero. 

Then, in May of 2023, Percy investigated a rock, dubbed “Ozuel Falls,” that turned out to definitely be worth celebrating. According to NASA, the rock’s analysis by Percy came back with a reading that was rich in the biosignature phosphate. 

The figure below shows Ouzel Falls with a list of materials identified within it, including large, millimeter-scale regions rich in phosphate. Data from PIXL is laid over the image. Colored squares show different areas where PIXL’s X-ray beam scanned the rock’s surface. Find NASA’s full discovery here.

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While perhaps not as exciting to non-scientists as the idea of Percy running into a little green man, rest assured, this is a big deal. Phosphorus is an element considered to be a cornerstone to the formation of life as we know it. It’s found in the DNA and cell membranes of all earthly life, and serves as a way to store and transfer energy within living things. 

Scientists at the USGS, like Dr. Ryan Anderson, Dr. Paul Giessler, and Dr. Lauren Edgar are currently members on the team helping Percy to explore geology, and are confident that this find is one of the first of many “Eureka!” moments that will be celebrated from this mission.

Knowing that we can obtain images of Mars with high resolution, obtain sample analysis that supports the argument for life on Mars, and get a helicopter to fly around in the thin atmosphere of the planet, we’re already impressed with the accomplishments on Mars being garnered. Despite that, we’re patiently waiting to see what we’ll find when humans finally make the trek to the fourth planet from the Sun, and are thrilled that the upcoming Artemis missions to the Moon will kick-off the advancement of human space exploration deeper into our solar system. 

If you want to make one of your resolutions this year staying up to date on the latest in planetary science, stay connected with our news and social media pages.