The search for habitable conditions beyond Earth has just become more interesting with the discovery of biologically available phosphorus from one of Saturn’s moons. Phosphorus is the most elusive of the six crucial elements needed for life.
In research published today in Nature, data from the Cassini spacecraft were used to find phosphorus compounds called phosphates in Saturn’s E ring – one of the fainter outer rings of the planet.
These compounds likely came from the ice volcano (cryovolcano) plumes from the sub-surface liquid water ocean on Saturn’s moon Enceladus.
A famous moon
Enceladus seemed like a typical moon of Saturn until the Cassini spacecraft came to take a closer look. Arriving at Saturn in 2005, Cassini has been making discovery after discovery that have catapulted Enceladus to one of the top places to look for life beyond Earth.
In particular, we learned Enceladus has a liquid water ocean beneath its icy surface, heated by gravitational tidal forcing – the kind of forcing that produces ocean tides on Earth.
The process of organic compounds making their way onto ice grains emitted in plumes from Saturn’s moon Enceladus, where they were detected by NASA’s Cassini spacecraft. NASA/JPL-Caltech
This environment is tantalisingly similar to the hydrothermal vents thought by some to be the place where life may have originated on Earth. Such vents certainly host life on Earth today.
Most life on Earth ultimately relies on photosynthesis – generating energy from sunlight. Meanwhile, the ultimate energy source for any life on Enceladus would be the gravity of Saturn producing tides far stronger than the Moon produces on Earth, allowing a liquid water ocean despite the very cold -200℃ ice crust surface.
Easy sampling
The Enceladus plumes have been called a “gimme” for efforts to sample the oceans of alien worlds. One wouldn’t need to land to collect a sample, nor to then launch to return it for analysis.
An obvious approach to sampling an ice volcano is to simply fly through it. However, this is difficult because the speed at which a space probe would encounter the plume would likely kill most organics.
Instead, the easiest approach is to examine the accumulation of ejected material from Enceladus in Saturn’s E ring, which is what the team did in this latest study.
Using this approach, researchers have previously discovered complex organic moleculescoming from Enceladus. These findings confirmed that the watery environment on Enceladus supports complex chemistry involving nitrogen and oxygen.
However, until now we didn’t know about the availability of phosphorus on Enceladus; in many environments this element is locked in rocks.
A crucial element
The discovery of phosphates in Saturn’s E ring suggests phosphates could be available within the oceans of Enceladus at a concentration 100 times higher than in Earth’s oceans.
Phosphorus is crucial for life as we know it, partly because it is a key building block of DNA and RNA, molecules essential to all life on Earth. Phosphate is also vital for a number of other metabolic processes in all life.
Many of the essential components necessary for the emergence of life as we know it have thus been discovered on Enceladus. This puts it at or near the top of lists of places to search for life beyond Earth in our Solar System.
Nevertheless, this discovery is only the start of the story. For phosphate to form bonds with carbon – this type of bond is found in the backbone of DNA – we need specialised chemistry that’s very dependent on the environment.
We’ll need further study of the chemistry in and under the crust of Enceladus. But a future detection of organic phosphate compounds would be particularly interesting for the potential for life in the moon’s oceans.
However, the detection method is quite different. On Venus the presence of phosphine was proposed by observing the atmosphere from Earth. The phosphates in this study were detected using an instrument orbiting Saturn called a mass spectrometer, which measured the mass of individual compounds found in the ice of the E ring.
To verify the analysis, the authors created a water solution on Earth very similar to the predicted Enceladus ocean.
That said, both detection methods carry a risk of misidentification, where a different molecule that’s not phosphine is actually responsible for the result.
It would be great to have a “smoking gun” for life beyond Earth, but realistically it will instead be a trickle of evidence that grows as we discover more about these environments.
The study published today is one more piece of evidence supporting the fact that Enceladus may be a great location in our search for extraterrestrial life.
Acknowledgements: We thank Prof Steve Benner from The Foundation For Applied Molecular Evolution for his insight and contributions to this article.
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.
