NASA's Perseverance Mars rover has now collected two rock samples, giving scientists insight into Mars' history.
The first sample named "Montdenier" was collected on September 6, and a second, "Montagnac", from the same rock on September 8, the US space agency said in a statement.
Analysis of the rocks from which the Montdenier and Montagnac samples were taken show signs that they were in contact with water for a long period of time, boosting the case for ancient life on the Red Planet.
aceIt looks like our first rocks reveal a potentially habitable sustained environment. It's a big deal that the water was there for a long time," said Ken Farley of Caltech, project scientist for the mission, which is led by NASA's Jet Propulsion Laboratory (JPL) in Southern California.
The rock that provided the mission's first core samples is basaltic in composition and may be the product of lava flows. The team also found salts within these rocks.
These salts may have formed when groundwater flowed through and altered the original minerals in the rock, or more likely when liquid water evaporated, leaving the salts.
The salt minerals in these first two rock cores may also have trapped tiny bubbles of ancient Martian water. If present, they could serve as microscopic time capsules, offering clues about the ancient climate and habitability of Mars.
According to the team, the level of alteration seen in the rock that provided the core samples -- as well as in the rock the team targeted on their first sample-acquisition attempt -- suggests that groundwater was present for a long time.
This groundwater could have been related to the lake that was once in Jezero, or it could have traveled through the rocks long after the lake had dried up. Though scientists still can't say whether any of the water that altered these rocks was present for tens of thousands or for millions of years, they feel more certain that it was there for long enough to make the area more welcoming to microscopic life in the past, the team explained.
Perseverance's next likely sample site is just 656 feet (200 meters) away in "South Seitah". a series of ridges covered by sand dunes, boulders, and rock shards that Farley likens to "broken dinner plates".
The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.