- Jonathan Amos
- BBC science correspondent
23 minutes ago
NASA’s Perseverance rover is nearing completion of its first goals for Mars exploration.
NASA’s robotic rover has collected various rock samples that will soon be placed on the surface of Mars by the rover, waiting for future Mars missions to bring the samples back to Earth.
Seventeen months ago, the rover was hoisted into the area known as the “Jezero Crater”.
What Perseverance’s footage has seen since then has confirmed to scientists that the rover has been sent to the best place to search for life on Mars.
The rover is not looking for any living organisms; the chances of an organism surviving in the harsh environment of Mars are slim to none. The probe is looking for traces of life left over billions of years ago, when Jezero Crater was a water-filled lake.
Scientists say the ‘amazing’ rock samples collected can record far back in history. The rock samples will be placed in a “storage site” on Mars in the coming months.
“If[ancient Jezero]conditions had been similar to those on Earth at any point in the past 2.5 billion years,” said Perseverance researcher David Shuster of the University of California, Berkeley, I think we can pretty much say — at least hypothesize — that biological activity leaves marks on rocks that we can observe.”
NASA and the European Space Agency are working together on plans to retrieve rock samples from Mars. The plan is bold and will use another Mars landing system, as well as helicopters, a Mars rocket and an interplanetary cargo spacecraft.
The goal is to ship rock samples back to Earth in 2023.
The rock samples include igneous, or volcanic, rocks that Perseverance drilled beneath the surface of Jezero Crater. These rocks can provide clues to the conditions before the crater formed the lake.
Crucially, the ages of these rock samples can be determined. The geological age on Mars can only be speculated indirectly at present.
Another rock sample is sedimentary rocks that Perseverance has collected in recent months from the delta there, west of the 45-kilometer-wide Jezero Crater.
As rivers flow into wider bodies of water, their flow slows, and silt and sand settle on the riverbed, creating raised areas called deltas. Such geological formations may retain traces of microbes that have existed in the past.
Satellite images show a huge raised surface formed by sediments west of Jezero Crater, a depression near Mars’ equator that has long been suspected to be a delta.
The Mars rover took samples of sedimentary rock from a rock known as Wildcat Ridge, which is formed when sediment was deposited in a crater lake and the lake’s water evaporated. Rocks are very salty. But the probe’s instruments showed that the Wildcat Ridge rock also contained enough organic or carbon-rich compounds.
This observation is significant but needs to be treated with caution.
“All known life is made of organic matter,” said Sunanda Sharma, a planetary scientist at NASA’s Jet Propulsion Laboratory. “But importantly, organic matter is also in a chemical process unrelated to life. formed in; for example, water and rock interactions. Organics are also found in interstellar dust.”
For the past four months, the Perseverance rover has been working on the 40-meter-high rock surface on the edge of the delta.
Soon the probe will leave the slope to the flat surface beneath a nearby crater, where it will place a rock sample outside in a titanium tube.
“We’re looking at the possibility of putting 10-11 rock samples on the surface of Mars,” said Rick Welch, a project engineer for Perseverance at NASA’s Jet Propulsion Laboratory.
“It may take about two months to get these rocks out and carefully record their locations so that future (going to Mars) projects can find these rock samples.”
NASA engineers have been rehearsing how to pop a titanium tube in the belly of the Perseverance rover. They have an exact replica of the rover at the Jet Propulsion Laboratory, and they do simulation exercises on it before they can go to Mars on a mission and actually complete the plan.
The final decision on whether to go to Mars is expected to be made at a NASA meeting on October 19.
Perhaps it was an insurance plan for the Perseverance rover to release the first rock samples, that is, if a catastrophic accident occurs during the subsequent mission of the rover, the stored rock samples can still be collected by later Mars rovers. sent back to earth.
The researchers hope to collect more samples of Martian rocks, so plans to sample from Mars focus on where the robotic probes will go in the future.
The final decision will be influenced by how activity on Mars progresses.
Lori Glaze, head of NASA’s planetary science division, praised the achievements of the Perseverance Mars rover team so far.
“Not only did we go to the right place, but we sent the right spacecraft with the right scientific instruments to explore the amazing ancient face of Mars,” she told reporters.