Aerial photos show the remains of a delta that once fed an ancient lake in Mars’ Jezero Crater. Credit: NASA/JPL-California Institute of Technology/ASU
Ground-penetrating radar reveals environmental changes over the years and offers hope that there are traces of life in soil samples.
- Equipped with underground radar NASA‘s Mars The Perseverance rover has confirmed that Jezero Crater, formed by an ancient meteorite impact just north of Mars’ equator, was once home to a vast lake and river delta.
- Over many years, the deposition and erosion of sediment within the crater formed the geological formations seen on the Earth’s surface today.
- The discovery of lake sediment raises hopes that the soil and rock samples collected by Perseverance may reveal signs of life.
![NASA Mars Perseverance Rover RIMFAX Ground Penetrating Radar](https://scitechdaily.com/images/NASA-Mars-Perseverance-Rover-RIMFAX-Ground-Penetrating-Radar.gif)
An animation showing the RIMFAX instrument aboard NASA’s Mars Perseverance spacecraft taking ground-penetrating radar measurements across the contact between the crater floor and the delta region of Mars’ Jezero Crater. Credit: Euibin Kim, David Paige, UCLA
If life existed on Mars, the Perseverance rover’s examination of lake sediments at the bottom of Jezero Crater raises hopes that traces may be found within the crater.
In a new study published in the journal scientific progressteam led by University of California Los Angeles And that University of Oslo This indicates that at some point the crater filled with water and a layer of sediment was deposited at the bottom of the crater. The lake then shrank, and the sediment carried by the rivers that fed it formed a huge delta. As the lake disappeared over time, the sediment within the crater eroded away, forming the geological features seen on the surface today.
![Mars Perseverance Rover RIMFAX Ground Penetrating Radar Measurement Hawksbill Gap](https://scitechdaily.com/images/Mars-Perseverance-Rover-RIMFAX-Ground-Penetrating-Radar-Measurements-Hawksbill-Gap-777x385.jpg)
Mars Perseverance Rover RIMFAX ground-penetrating radar measurements of the Hawksbill Gap region in the western delta of Jezero Crater on Mars. Hawksbill Gap. Credit: Svein-Erik Hamran, Tor Berger, David Paige, University of Oslo, UCLA, California Institute of Technology Jet Propulsion Laboratory, NASA
Radar shows that the period of deposition and erosion occurred amidst persistent environmental change, confirming that inferences about Jezero Crater’s geological history based on Mars images obtained from space are accurate. It is supported.
“While we can see a variety of mineral deposits from orbit, we cannot know for sure whether we are looking at their original state or whether we are seeing the end of a long geological story. We can’t,” David Page said. Professor of Earth, Planetary, and Space Sciences at the University of California, Los Angeles, and lead author of the paper. “You have to look below the surface to see how these things formed.”
AI-interpolated video from NAVCAM images of the NASA Perseverance rover’s crossing of the Jezero West Delta from Cape Nukshak to the crater floor of Sol 641.Credit: Lior Rubanenko, Emily Cardarelli, Justin Maki, David Paige, UCLA, California Institute of Technology NASA Jet Propulsion Laboratory
The rover, which is about the size of a car and carries seven scientific instruments, has been exploring the 30-mile-wide crater since 2021, studying its geology and atmosphere and collecting samples. Perseverance’s soil and rock samples will be returned to Earth. Future expeditions studied evidence of past life.
Perseverance reached the delta from the crater floor between May and December 2022. The delta region is a vast area of 3 billion-year-old sediments that resembles Earth’s delta region when viewed from orbit.
![Mars Perseverance Rover RIMFAX Ground Penetrating Radar Measurement Hawksbill Gap Region](https://scitechdaily.com/images/Mars-Perseverance-Rover-RIMFAX-Ground-Penetrating-Radar-Measurements-Hawksbill-Gap-Region-777x381.jpg)
Mars Perseverance Rover RIMFAX ground-penetrating radar measurements of the Hawksbill Gap region in the western delta of Jezero Crater on Mars. Credit: Svein-Erik Hamran, Tor Berger, David Paige, University of Oslo, UCLA, California Institute of Technology Jet Propulsion Laboratory, NASA
When the spacecraft enters the delta area, Perseverance’sRadar imager for underground experiments on Mars, RIMFAX fired radar waves downward at 10-centimeter intervals and measured the reflected pulses at a depth of about 20 meters below the surface. Using radar, scientists can peer down to the bottom of the sediment and reveal the top surface of the buried crater floor.
Years of research with ground-penetrating radar and RIMFAX tests on Earth have taught scientists how to read the structure and composition of underground layers from radar reflections. The resulting subsurface image displays rock formations that can be interpreted like highway road cuts.
“Some geologists say that radar’s ability to see below the surface is a form of cheating,” says Page, RIMFAX’s deputy principal investigator.
![Mars Perseverance Rover RIMFAX Ground Penetrating Radar Measurement Cape Nukushaku](https://scitechdaily.com/images/Mars-Perseverance-Rover-RIMFAX-Ground-Penetrating-Radar-Measurements-Cape-Nukshak-777x297.jpg)
Ground-penetrating radar measurements taken by the Mars Perseverance Rover RIMFAX in the Cape Nukushak region of the Jezero Crater West Delta on Mars. Credit: Svein-Erik Hamran, Tor Berger, David Paige, University of Oslo, UCLA, California Institute of Technology Jet Propulsion Laboratory, NASA
RIMFAX imaging revealed two distinct periods of sediment deposition sandwiched between two periods of erosion. UCLA and the University of Oslo report that the crater floor beneath the delta is not uniformly flat, suggesting that a period of erosion occurred before the lake sediments were deposited. Radar images show that the sediment is regular and horizontal, similar to sediment deposited in lakes on Earth. Previous research had suspected the presence of lake sediment, but this study confirmed it.
The second period of deposition occurred when the river deposited a wide delta area due to fluctuations in lake levels. The delta region once extended deep into the lake, but has now eroded back to near the mouth of the river.
“The changes preserved in the rock record are driven by large-scale changes in the Martian environment,” Page said. “It’s great to see so much evidence of change in such a small geographic area and to be able to extend our findings to the scale of the entire crater.”
Reference: “Ground-penetrating radar observations showing contact between Mars’ western delta and the crater floor of Jezero Crater” by David A. Page, Svein Erik Hamran, Hans EF Amundsen, Thor Berger, and Patrick Russell. , Reva Kakaria, Michael T. Mellon, Sigurd Eide, Lin M. Carter, Titus M. Casademont, Daniel C. Nunez, Emily S. Shoemaker, Dirk Pretmeyer, Henning Dypvik, Sanna Holm-Alwmark, Bryony H.N. Hogan, January 26, 2024, scientific progress.
DOI: 10.1126/sciadv.adi8339
This research received funding from NASA, the Norwegian Research Council, and the University of Oslo.