The Perseverance rover uncovered a rock fragment and found green spots inside.

The crater's name, Jezero, is quite telling, especially for speakers of Slavic languages. It translates to "lake." Planetologists have determined that this 49-kilometer indentation was formed by an asteroid impact approximately 3.8 to 3.9 billion years ago, which is just 700 million years after the formation of Mars and the entire Solar System, and it soon filled with water.

To this day, the crater is adjacent to an entire system of winding, elongated structures, which geologists confidently assert are riverbeds. This is precisely why Jezero was chosen for the Perseverance rover.

Since February 2021, the rover has traveled 30 kilometers. From time to time, it leaves behind capsules containing soil collected with its drill, which penetrates to a depth of about six centimeters. This gives great hope for the search for potential signs of extraterrestrial life: the soil protects against radiation, to which the Martian surface is almost defenseless due to the extremely weak magnetic field of the Red Planet and its sparse atmosphere.

In addition to the drill, Perseverance is equipped with another similar "tool," which does not penetrate deeply but rather scrapes the upper layer of rock. Using this abrasive method, the rover recently interacted with a curious stone located near the mouth of the ancient Neretva River, which flowed into Jezero.

On the surface, as is typical on Mars, it is "rusted" from oxidized iron, but beneath the chipped fragments, areas of several different colors were discovered. At NASA, they admitted that the pale green spots were a particular surprise.

Researchers explained that this is the color of reduced iron. On Earth, this occurs when water seeps through the rock and triggers a reduction reaction. Scientists mentioned that sometimes this reaction involves microbes.

Furthermore, such marks may be traces of the decomposition of organic materials that created conditions for reduction. NASA lamented that they could not properly position the rover's instruments to study these greenish spots, so their composition could not be definitively established.

During the fertile times of this crater "lake," the Martian atmosphere had a density similar to that of Earth, and the air warmed up to 50 degrees Celsius. It is no wonder that scientists are asking whether even the most primitive single-celled life could have formed there. After all, on Earth, traces of life have been found in rocks over four billion years old.