Extract from ABC News
NASA's Perseverance Rover discovers Mars bedrock formed from magma, rocks interacted with water.
Scientists with NASA's Perseverance Mars rover mission have discovered that the bedrock their six-wheeled explorer has been driving on since landing in February likely formed from red-hot magma.
Key points:
- Rocks in a Mars crater have interacted with water and contain organic molecules
- Researchers say more analysis needs to be done to determine the method which produced the organics
- The rover landed on Mars in March with the main goal of searching for signs of life on the planet
The team has also concluded that rocks in the Jezero crater have interacted with water multiple times over the eons and that some contain organic molecules.
Even before Perseverance touched down on Mars, the mission's science team had wondered about the origin of the rocks in the area.
"I was beginning to despair we would never find the answer," said Perseverance Project Scientist Ken Farley.
"But then our PIXL instrument got a good look at the abraded patch of a rock from the area nicknamed 'South Seitah,' and it all became clear.
PIXL, the Planetary Instrument for X-ray Lithochemistry, uses an X-ray spectrometer to identify chemical elements.
The drill at the end of Perseverance's robotic arm can grind rock surfaces to allow instruments such as PIXL to study them.
In November, Perseverance used its robotic arm to analyse a South Seitah rock nicknamed "Brac".
The data showed the rock to be composed of an unusual abundance of large olivine crystals engulfed in pyroxene crystals.
"A good geology student will tell you that such a texture indicates the rock formed when crystals grew and settled in a slowly cooling magma — for example, a thick lava flow, lava lake, or magma chamber," said Mr Farley.
Still to be determined is whether the olivine-rich rock formed in a thick lava lake cooling on the surface or in an underground burial chamber of lava that was later exposed by erosion.
Dr David Flannery from The Queensland University of Technology has been working very closely with NASA on the Perseverance Rover project.
He was a part of the team in Australia that helped with the science and built the data analysis software that led to NASA's latest discovery.
They were all very surprised and excited about what the rover found.
"We can get the date of the surface of Mars for the first time.
Dr Flannery said the operation is still in the early stages and is expected to continue for many years.
"We need another mission to collect more rocks from Mars," he said.
"We intended to drive this rover across the entire crater, but we are in the early stage of this mission."
Rover's search for life
The rover landed on Mars on February 2021 with its main goal to search for signs of life on Mars.
Perseverance, about the size of a car, gathers samples and either analyses the samples with its on-board laboratory or it can save them for return to Earth by future missions.
NASA hopes the rover can characterise the planet's geology and past climate to help pave the way for human exploration of the Red Planet.
Of Perseverance's 43 sample tubes, six have been sealed to date — four with rock cores, one with Martian atmosphere, and one that contained "witness" material to observe any contamination the rover might have brought from Earth.
Mars Sample Return seeks to bring select tubes back to Earth, where generations of scientists will be able to study them with powerful lab equipment far too large to send to Mars.
More 'exciting' discoveries
The multi-mission Mars Sample Return campaign began with Perseverance, but involves NASA's SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) instrument.
SHERLOC found carbon-containing molecules are not only in the interiors of abraded rocks but also in the dust on non-abraded rock.
Confirmation of organics does not mean that life once existed in Jezero crater.
There are both biological and non-biological mechanisms that create organics — a term that simply refers to carbon chemistry, not the chemistry of organic processes.
"Curiosity also discovered organics at its landing site within Gale Crater," said Luther Beegle, SHERLOC principal investigator at NASA's Jet Propulsion Laboratory.
"This helps us understand the environment in which the organics formed.
"More analysis needs to be done to determine the method of production for the identified organics."
The preservation of organics inside ancient rocks — regardless of origin — at both Gale and Jezero Craters on Mars does mean that signs of life, whether past or present, could be preserved.
"This is a question that may not be solved until the samples are returned to Earth, but the preservation of organics is very exciting.
"When these samples are returned to Earth, they will be a source of scientific inquiry and discovery for many years," Mr Beegle said.
Reuters/ABC
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