Exploring the ‘delta front’ of Jezero Crater, NASA’s Perseverance rover has found the strongest signs yet that life once existed on Mars.
Are we alone in the universe? This is one of the most important questions that science has been trying to answer for us. Building on previous discoveries, the Perseverance rover is helping answer that question. If it found evidence that there was once life on Mars, a planet that was once warmer and wetter but is now very inhospitable, there is a good chance that life is abundant throughout the cosmos.
Perseverance is currently roving next to an ancient river delta on Mars, taking samples and using its instruments to scan the various rock deposits. Here on Earth, river deltas are teeming with life. They are also places where the signs of past life — organic compounds — become concentrated in the layers of sediment and rock as they build up over time. So, if life did develop on Mars long ago, a river delta like the one in Jezero crater is just about the best place to look for those same signs of life.
This map of the western edge of Jezero Crater shows the path of the Perseverance rover since its mission began in February 2021 (white line), and the rover’s current location (red star). Credit: NASA
When the rover collected two of its latest samples, from Skinner Ridge and Wildcat Ridge, it sent back some exciting results.
While the rocks appear quite different, they both formed in a habitable environment. That is, the conditions at the time and place where these rock deposits were laid down were friendly to life as we know it. However, the fine-grain structure and lighter colour of the Wildcat Ridge sample made it particularly interesting.
These two abrasion patches show the Skinner Ridge sample rock (left), which is made of larger rounded grains cemented together, and the Wildcat Ridge sample rock (right), which is smooth and fine-grained. Both are exactly the kind of rocks NASA is looking for to find potential biosignatures. Credit: NASA
“In the distant past, the sand, mud, and salts that now make up the Wildcat Ridge sample were deposited under conditions where life could potentially have thrived,” Perseverance project scientist Ken Farley, from Caltech, said in a NASA press release.
Scanning the Wildcat Ridge abrasion patch using SHERLOC, the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals, Perseverance detected a treasure-trove of organic compounds.
“In Wildcat Ridge, we detected signals that we think are from a class of organic matter called aromatics, which are stable molecules made up of carbon, hydrogen, and sometimes other elements, with ring structure,” Sunanda Sharma, the SHERLOC scientist at NASA’s Jet Propulsion Laboratory, said during a press briefing on these results on Thursday.
“These signals were present in nearly every single point, in every scan. They are also some of the brightest that we’ve seen thus far on the mission, and they are about seven times brighter than what we saw at Thorton Gap, which is the abration patch on Skinner Ridge,” Sharma explained.
According to Sharma, these aromatics were found alongside sulphate minerals. Similar conditions have been found here on Earth, where sulphates tend to preserve organic compounds. This suggests that these Martian organics and sulphates were deposited and concentrated in this location of the delta as the lake in Jezero Crater dried up.
“This makes these samples and this set of observations some of the most intriguing that we’ve done so far on the mission, and it fulfills some of the excitement that the team had when we were approaching the delta front,” Sharma said.
This discovery confirms that Perseverance was definitely sent to the right place on Mars, with the right set of tools, to conduct its search for signs of ancient life.
This composite image of the delta front puts the rover’s latest samples into context, showing the locations of the Wildcat Ridge and Skinner Ridge sampling areas. The inset views show mosaic views from the rover of each after a sample was drilled from the rock. Credit: NASA/Scott Sutherland
But what’s the truly exciting part of all this? Perseverance’s SHERLOC instrument picked up signs of organic matter in these rocks. While the rover has already found organic compounds in other areas of the crater, the Wildcat Ridge sample showed the strongest detection of organics so far!
Signs of life? Maybe…
What Perseverance has found here are ‘potential biosignatures’.
Finding organic compounds in the rock samples isn’t a definitive sign of life. Something being an “organic” compound simply means that the molecules contain carbon atoms (and usually hydrogen, oxygen, and other elements like nitrogen, phosphorus and sulphur). While many organic compounds are part of biological life forms or are produced by those life forms, some are formed through geological processes. So, just detecting organics isn’t a definitive sign of life.
To find ‘definitive biosignatures’ — absolutely conclusive proof that life existed on Mars at one time — we’ll need to wait.
“The fact the organic matter was found in such a sedimentary rock — known for preserving fossils of ancient life here on Earth — is important. However, as capable as our instruments aboard Perseverance are, further conclusions regarding what is contained in the Wildcat Ridge sample will have to wait until it’s returned to Earth for in-depth study as part of the agency’s Mars Sample Return campaign,” Farley explained in the NASA press release.
Mars Sample Return
So, how long of a wait do we have?
Lori Glaze, the director of NASA’s Planetary Science Division, laid out the timeline of the Mars Sample Return campaign during Thursday morning’s briefing.
“The Earth Return Orbiter, that will carry the samples back to Earth, is expected to launch in 2027 in our current design,” Glaze said. “The Sample Return Lander will launch a few months later, in the spring of 2028.”
This artist’s conception drawing shows the different elements of the Mars Sample Return campaign, with the lander (bottom right), sample retrieval drone (centre, left), Mars ascent vehicle (top right), and Earth Return Orbiter (top), all cooperating with Perseverance to complete the mission. Credit: NASA/JPL-Caltech
When the Sample Return Lander arrives, it will use two drone helicopters similar to Ingenuity to collect the sample tubes from where Perseverance has dropped them on the surface. Meanwhile, the rover will also drive to the lander’s position to add the rest of its samples to the return payload.
As Glaze explained, those samples will be launched into orbit around Mars sometime in 2030, and they will make the trip on board the Earth Return Orbiter to arrive here on Earth in 2033.
With direct access to those samples and the most advanced laboratories on Earth, scientists can confirm the source of the organic compounds and perhaps bring us one step closer to knowing if alien life really exists.
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.
