This graphic depicts Perseverance’s entry into “Séítah” from both an orbital and subsurface perspective. The lower image is a subsurface “radargram” from the rover’s RIMFAX instrument; the red lines indicate link subsurface features to erosion-resistant rocky outcrops visible above the surface. Credit: NASA/JPL-Caltech/University of Arizona/USGS/FFI
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. The discovery has implications for understanding and accurately dating critical events in the history of Jezero Crater—as well as the rest of the planet.
The team has also concluded that rocks in the crater have interacted with water multiple times over the eons and that some contain organic molecules.
These and other findings were presented today during a news briefing at the American Geophysical Union fall science meeting in New Orleans.
Even before Perseverance touched down on Mars, the mission’s science team had wondered about the origin of the rocks in the area. Were they sedimentary—the compressed accumulation of mineral particles possibly carried to the location by an ancient river system? Or where they igneous, possibly born in lava flows rising to the surface from a now long-extinct Martian volcano?
“I was beginning to despair we would never find the answer,” said Perseverance Project Scientist Ken Farley of Caltech in Pasadena. “But then our PIXL instrument got a good look at the abraded patch of a rock from the area nicknamed “South Séítah,” and it all became clear: The crystals within the rock provided the smoking gun.”
The drill at the end of Perseverance’s robotic arm can abrade, or grind, rock surfaces to allow other instruments such as PIXL to study them. Short for Planetary Instrument for X-ray Lithochemistry, PIXL uses X-ray fluorescence to map the elemental composition of rocks. On Nov. 12, PIXL analyzed a South Séítah rock the science team had chosen to take a core sample from using the rover’s drill. The PIXL data showed the rock, nicknamed “Brac,” 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 Farley. “The rock was then altered by water several times, making it a treasure trove that will allow future scientists to date events in Jezero, better understand the period in which water was more common on its surface, and reveal the early history of the planet. Mars Sample Return is going to have great stuff to choose from.”
The multi-mission Mars Sample Return campaign began with Perseverance, which is collecting Martian rock samples in search of ancient microscopic life. 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.
Still to be determined is whether the olivine-rich rock formed in a thick lava lake cooling on the surface or in a subterranean chamber that was later exposed by erosion.
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Taken by Perseverance’s Mastcam-Z instrument, this video features an enhanced-color composite image that pans across Jezero Crater’s delta on Mars. The delta formed billions of years ago from sediment an ancient river carried to the mouth of a lake that once existed in the crater. Credit: NASA/JPL-Caltech/ASU/MSSS
Organic molecules
Also great news for Mars Sample Return is the discovery of organic compounds by the SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) instrument. The carbon-containing molecules are not only in the interiors of abraded rocks SHERLOC analyzed, but in the dust on non-abraded rock.
Confirmation of organics is not a confirmation that life once existed in Jezero and left telltale signs (biosignatures). There are both biological and non-biological mechanisms that create organics.
“Curiosity also discovered organics at its landing site within Gale Crater,” said Luther Beegle, SHERLOC principal investigator at NASA’s Jet Propulsion Laboratory in Southern California. “What SHERLOC adds to the story is its capability to map the spatial distribution of organics inside rocks and relate those organics to minerals found there. 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 does mean that potential biosignatures (signs of life, whether past or present) could be preserved, too. “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,” Beegle said.
Six facsimile sample tubes hang on the sample tube board. Credit: NASA/JPL-Caltech
‘Radargram’
Along with its rock-core sampling capabilities, Perseverance has brought the first ground-penetrating radar to the surface of Mars. RIMFAX (Radar Imager for Mars’ Subsurface Experiment) creates a “radargram” of subsurface features up to about 33 feet (10 meters) deep. Data for this first released radargram was collected as the rover drove across a ridgeline from the “Crater Floor Fractured Rough” geologic unit into the Séítah geologic unit.
The ridgeline has multiple rock formations with a visible downward tilt. With RIMFAX data, Perseverance scientists now know that these angled rock layers continue at the same angle well below the surface. The radargram also shows the Séítah rock layers project below those of Crater Floor Fractured Rough. The results further confirm the science team’s belief that the creation of Séítah preceded Crater Floor Fractured Rough. The ability to observe geologic features even below the surface adds a new dimension to the team’s geologic mapping capabilities at Mars.
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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
