“Mars once was wet and fertile. It’s now bone dry,” said Cosmos host, Neil deGrasse Tyson, “Something bad happened on Mars. I want to know what happened on Mars so that we may prevent it from happening here on Earth.”
Mars is crisscrossed with distinctive tracks of big, long-dead rivers but scientists still don’t know what kind of weather fed them, because their understanding of the Martian climate billions of years ago remains incomplete. It remains a puzzle why ancient Mars had liquid water. Early in the planet’s history, Mars only receiving a third of the sunlight of present-day Earth, which shouldn’t be enough heat to maintain liquid water. But that is but one of a myriad of unsolved mysteries about the Red Planet.
Today, Mars is a frigid, barren land unchanged for hundreds of millions of years, motionless except for the scattering of red dust by a faint breeze, or the slow hum of a “curious” alien rover. In 2013, planetary scientists at the European Space Agency released 3D images of the “striking upper part of the Reull Vallis region of Mars,” which revealed a huge, 932-mile-long (1500 kilometer) river running from the Promethei Terra Highlands to the vast Hellas basin. The image data from ESA’s Mars Express spacecraft shows that, at some points, the riverbed is 4.3 miles (7 kilometers) wide and 984 feet (300 meters) deep. The stereo cameras onboard the satellite also revealed “numerous tributaries” that fed the gigantic river.
Later, a 2019 study by University of Chicago scientists concluded that significant river runoff persisted on Mars later into its history than previously thought. According to the study, published in Science Advances, the runoff was intense—rivers on Mars were wider than those on Earth today—and occurred at hundreds of locations on the red planet.
Challenge to “Warm and Wet Ancient Mars”
Now, according to according to new University of British Columbia research published in Nature Geoscience, a large number of the valley networks scarring Mars’s surface were carved by water melting beneath glacial ice, not by free-flowing rivers as previously thought. The findings challenge the dominant “warm and wet ancient Mars” hypothesis, which postulates that rivers, rainfall and oceans once existed on the red planet.
To reach this conclusion, lead author Anna Grau Galofre at the department of earth, ocean and atmospheric sciences, developed and used new techniques to examine thousands of Martian valleys. She and her co-authors also compared the Martian valleys to the subglacial channels in the Canadian Arctic Archipelago and uncovered striking similarities.
“For the last 40 years, since Mars’s valleys were first discovered, the assumption was that rivers once flowed on Mars, eroding and originating all of these valleys,” says Grau Galofre. “But there are hundreds of valleys on Mars, and they look very different from each other. If you look at Earth from a satellite you see a lot of valleys: some of them made by rivers, some made by glaciers, some made by other processes, and each type has a distinctive shape. Mars is similar, in that valleys look very different from each other, suggesting that many processes were at play to carve them.”
The similarity between many Martian valleys and the subglacial channels on Devon Island in the Canadian Arctic (above) motivated the authors to conduct their comparative study. “Devon Island is one of the best analogues we have for Mars here on Earth–it is a cold, dry, polar desert, and the glaciation is largely cold-based,” says co-author Gordon Osinski, professor in Western University’s department of earth sciences and Institute for Earth and Space Exploration.
Collage above shows Mars’s Maumee valleys (top half) superimposed with channels on Devon Island in Nunavut (bottom half). The shape of the channels, as well as the overall network, appears almost identical. (Cal-Tech CTX mosaic and MAXAR/Esri).
10,000 Martian Valleys Analyzed
In total, the researchers analyzed more than 10,000 Martian valleys, using a novel algorithm to infer their underlying erosion processes. “These results are the first evidence for extensive subglacial erosion driven by channelized meltwater drainage beneath an ancient ice sheet on Mars,” says co-author Mark Jellinek, professor in UBC’s department of earth, ocean and atmospheric sciences. “The findings demonstrate that only a fraction of valley networks match patterns typical of surface water erosion, which is in marked contrast to the conventional view. Using the geomorphology of Mars’ surface to rigorously reconstruct the character and evolution of the planet in a statistically meaningful way is, frankly, revolutionary.”
Grau Galofre’s theory also helps explain how the valleys would have formed 3.8 billion years ago on a planet that is further away from the sun than Earth, during a time when the sun was less intense. “Climate modelling predicts that Mars’ ancient climate was much cooler during the time of valley network formation,” says Grau Galofre, currently a SESE Exploration Post-doctoral Fellow at Arizona State University. “We tried to put everything together and bring up a hypothesis that hadn’t really been considered: that channels and valleys networks can form under ice sheets, as part of the drainage system that forms naturally under an ice sheet when there’s water accumulated at the base.”
Better Survival Conditions for Early Life
These environments would also support better survival conditions for possible ancient life on Mars. A sheet of ice would lend more protection and stability of underlying water, as well as providing shelter from solar radiation in the absence of a magnetic field–something Mars once had, but which disappeared billions of years ago.
While Grau Galofre’s research was focused on Mars, the analytical tools she developed for this work can be applied to uncover more about the early history of our own planet. Jellinek says he intends to use these new algorithms to analyze and explore erosion features left over from very early Earth history.
“Currently we can reconstruct rigorously the history of global glaciation on Earth going back about a million to five million years,” says Jellinek. “Anna’s work will enable us to explore the advance and retreat of ice sheets back to at least 35 million years ago–to the beginnings of Antarctica, or earlier–back in time well before the age of our oldest ice cores. These are very elegant analytical tools.”
Tools that may provide Neil deGrasse Tyson with his long sought answer.
Image credit top of page: ESA & MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA, CC BY-SA IGO 3.0 True color image of Mars taken by the OSIRIS instrument on the ESA Rosetta spacecraft during its February 2007 flyby of the planet.
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.
