Rocks on Mars may hold clues to ancient life on the planet. NASA hopes to return the samples as early as 2033.
A team of scientists from NASA ‘s Perseverance mission has collected the first samples of water-altered Martian rocks that could be transported to Earth, providing the first step toward learning whether the Red Planet once harbored life.
As published in the journal ‘ Science ‘, the rock samples come from the floor of the Jezero crater , which was chosen as the study site because it has a large river delta that once flowed into an ancient lake.
The theory behind Jezero
Scientists believe that an aquatic Mars could have supported life billions of years ago. “These types of environments on Earth are places where life thrives. The goal of exploring the Jezero delta and crater is to search these once-inhabitable environments for rocks that may contain evidence of ancient life,” explains the astrobiologist and professor of University of Florida geologist Amy Williams, one of the long-term planners for NASA’s Perseverance mission, helps decide where to send the rover and what tests and samples to prioritize.
The rover is exploring the river delta to collect more rock samples for the Mars Sample Return mission . Directed for the mission by NASA ‘s Jet Propulsion Laboratory , Perseverance touched down at the bottom of Jezero Crater in February 2021. Since then, scientists have explored the geological composition of the crater floor using a suite of tools aboard the rover that can take photos and analyze the chemical composition of rocks, as well as see their structure underground.
The science team found that the crater floor had eroded more than expected. The erosion uncovered a crater composed of rocks formed by lava and magma, known as igneous rocks. Scientists originally expected that sedimentary rocks from lakes or deltas would lie on top of these igneous rocks. It is likely that the softer sedimentary rocks were worn down over the centuries, leaving behind the stronger igneous rocks.
The rocks that scientists analyzed and stored to return to Earth have been altered by water, further evidence of an aquatic past on Mars. “We have organisms on Earth that live in very similar rock types,” recalls Williams. “And aqueous alteration of minerals has the potential to record biosignatures.”
NASA and the European Space Agency plan to return the rock samples to Earth around 2033. The ambitious plan calls for building the first vehicle that can launch from the surface of Mars and rendezvous with an orbiter to transport the samples back. to the earth.
The reward for this task will be very detailed studies of the rock samples that cannot be carried out on the rover. These studies include measuring the age of rocks and looking for signs of ancient life. Since the rock samples taken from the bottom of the crater probably predate the river delta, dating these rocks will provide important information about the age of the lake. “I’m excited about what comes next,” says Williams.
( EuropaPress )