The Perseverance rover, part of NASA’s Mars 2020 mission, is on the brink of a transformative exploration phase that could significantly deepen our understanding of the red planet. As it prepares to emerge from the Jezero Crater, planetary scientist Briony Horgan from Purdue University eagerly anticipates the revelations that await just beyond the crater’s rim.
Horgan, who serves as a co-investigator and long-term planner for the mission, likens the crater’s edge to a cliff that opens up into an entirely new world. “We’re going to be getting our first views of some of the oldest rocks we’re going to see on the mission,” she remarked. These rocks, dating back over 4 billion years, hold the potential to unlock secrets about Mars’ geological history and its environmental conditions during a time long before it became the arid landscape we see today.
At the heart of the exploration lies an important question: Could Mars have once harbored microbial life? Horgan views every Martian rock as a time capsule, possibly containing evidence from a period when the planet was more hospitable. She emphasizes, “Finding evidence of microbial life, even from billions of years ago, would open the door to new research in understanding how common simple life forms are in the universe.” The implications of such a discovery could resonate through the scientific community, prompting further investigations into the potential for life on other celestial bodies.
The journey of Perseverance began with a launch in July 2020, covering a staggering distance of 300 million miles before landing in Jezero Crater in February 2021. This crater, once a lake, serves as a prime location for exploring the history of water on Mars. Horgan, prior to the rover’s launch, played a pivotal role in the selection of Jezero Crater by studying its mineralogy, which revealed its suitability for in-depth research.
As Perseverance ascends the crater rim—approximately half a mile vertically from its landing site—it is set to roll into the Isidis Planitia basin. This ancient watershed, formed by a significant impact nearly 4 billion years ago, is interlaced with riverbeds that once fed the lake within Jezero Crater. “Rocks that are this old are very rare on Earth,” Horgan explains, noting that they have typically been eroded or destroyed through geological processes. The opportunity to study such ancient materials is unparalleled and could yield insights into the building blocks of Earth-like planets.
Emerging from the crater also provides an opportunity to investigate hydrothermal environments potentially created by the impacts that formed Jezero and Isidis. Horgan posits that these environments may have offered warm water circulating through cracks in the rocks, creating habitable conditions if life had ever emerged on Mars.
As the mission progresses, Horgan emphasizes the unpredictability of the rover’s journey post-crater. “It’s a moving target,” she comments, as the mission team weighs the next steps based on the samples already collected. The rover has gathered a wealth of data, including 25 rock samples and one atmospheric sample, all of which could shed light on how water interacted with various rocks and minerals—essential in understanding the potential biosignatures of ancient Martian life.
The discovery of diverse geological features on Mars has already begun to challenge the traditional view of the planet as merely a dusty red sphere. Recently, Perseverance found a field of blue-colored volcanic basalt stones and an intriguing black-and-white zebra-striped rock, exemplifying the planet’s complex geological history and variety.
In the coming weeks, as the Perseverance rover traverses the crater rim, scientists around the world will be watching closely. The insights gained from this new terrain could not only illuminate the history of Mars but could also offer clues about the formation of planets and the conditions necessary for life throughout the universe.
