The northern lowlands and sedimentary regions of Mars are dotted with curious formations. Tens of thousands of conical hills, many topped with small craters, and surrounded by deep channels scoured from the surface by flowing liquid.
That sounds a lot like volcanoes found here on Earth – but on a planet like Mars, where we can’t easily go and look, and where conditions can be so very different from Earth’s, you have to be wary of making assumptions.
The features on Mars may resemble Earth’s lava flows, but there’s also a type of volcano on Earth that spews up something completely different – sludgy, oozy mud.
And scientists have just found that, under the very low atmospheric pressure and temperature conditions found on Mars, mud can flow very differently from Earth’s mud volcanoes. In fact, it can look a heck of a lot like lava.
“We performed experiments in a vacuum chamber to simulate the release of mud on Mars,” said planetary scientist Lionel Wilson of Lancaster University in the UK.
“This is of interest because we see many flow-like features on Mars in spacecraft images, but they have not yet been visited by any of the roving vehicles on the surface and there is some ambiguity about whether they are flows of lava or mud.”
(NASA/JPL-Caltech/University of Arizona)
Scientists have long thought that large amounts of water once flowed freely on the Martian surface, released for a very short period of time and eroding the landscape before drying up, or being covered by volcanic activity and sediments deposited by the wind.
But soggy sediments trapped under the surface could have later been pushed up and out by underground pressure, creating mud volcanoes. This is what the researchers wanted to figure out.
Their experimental set-up consisted of a low-pressure cylindrical chamber 90 centimetres in diameter and 180 centimetres in length (35 to 70 inches). This was carefully pressurised at 7 millibars to simulate Mars atmospheric pressure for 15 experiments, and 1,000 millibars to simulate Earth atmospheric pressure at sea level for 6 experiments.
In both sets, mud was poured over sand cooled to a temperature consistent with the surface temperature of Mars, -20 degrees Celsius. The researchers then studied and characterised the way the mud flowed across that surface.
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In terrestrial conditions, the mud flows didn’t expand, form an icy crust, or create lava-like flows. But the mud flows under Martian conditions did – because of the lower atmospheric pressure.
When atmospheric pressure lowers, so too does the boiling point of water. That’s why water boils at a lower temperature at higher altitudes; if you were to find yourself floating in space without protective gear, saliva would boil right off your tongue (among other, more fatal things).
The effect on mud flows in simulated Martian conditions is fascinating. The water in the mud begins to boil and evaporate, and that process absorbs the latent heat from the vapour. This cools the mud, and a crust freezes on its surface.
“Of course, we already know that liquid water begins to boil sooner under low pressure,” said planetary scientist Ernst Hauber of the DLR Institute of Planetary Research in Germany.
“However, the impact of this familiar effect on mud has never been investigated in an experiment before. Once again, it turns out that different physical conditions must always be taken into account when looking at apparently simple surface features on other planets. We now know that we need to consider both mud and lava when analysing certain flow phenomena.”
What happens after the crust freezes is where it gets really good. The mud flow behaves like the pahoehoe lava flows seen in Hawaii and Iceland. The mud still pushing up from underneath erupts through the icy crust, oozing out and refreezing into a new flow lobe. But, while the process is similar, the shape of the mud flows is different, the researchers found.
While there are limitations to the study – Martian gravity couldn’t be replicated, for instance – the research does show that mud volcanism wouldn’t be impossible on the Red Planet after all. And the research has important implications for other kinds of volcanism in the Solar System, such as the ice volcanoes thought to exist on far objects such as Titan and Pluto.
It shows that, even though we may think we understand what’s going on, there could be environmental conditions that change the processes in fundamental ways.
As geophysicist Petr Brož of the Czech Academy of Sciences said, “our experiments show that even a process as apparently simple as the flow of mud – something that many of us have experienced for ourselves since we were children – would be very different on Mars.”
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.
