Saturn’s rings are one of the most well-known features throughout astronomy. While much is known about them, they still make headlines from time to time. This includes a recent study involving an international team of researchers that could help paint a clearer picture of the interaction between the gas giant and the massive ring system that encircles it.
For the study, the researchers used a combination of data gathered between 1980 and 2017 from both active and retired space missions to examine ultraviolet (UV) observations of atomic hydrogen emissions within the upper atmosphere of Saturn that appear as a spectral line of hot hydrogen.
What they discovered was a first-of-its-kind view of Saturn and indications that its massive ring system is responsible for heating the gas giant’s atmosphere. In this case, icy particles from the rings rain down from a combination of Saturn’s immense gravity and other possibilities, including solar ultraviolet radiation, micrometeorite impacts, electromagnetic forces, and bombardment from the solar wind. In fact, NASA’s Cassini confirmed the raining of particles from the rings during its atmospheric plunge into Saturn, also known as the “Grand Finale”, in 2017.
“Though the slow disintegration of the rings is well known, its influence on the atomic hydrogen of the planet is a surprise. From the Cassini probe, we already knew about the rings’ influence. However, we knew nothing about the atomic hydrogen content,” said Dr. Lotfi Ben-Jaffel of the Institute of Astrophysics in Paris and the Lunar & Planetary Laboratory at the University of Arizona, and lead author of the study. “Everything is driven by ring particles cascading into the atmosphere at specific latitudes. They modify the upper atmosphere, changing the composition. And then you also have collisional processes with atmospheric gases that are probably heating the atmosphere at a specific altitude.” The ring disintegration on Saturn that Dr. Ben-Jaffel mentions likely comes from a 2018 study that confirmed Saturn could lose all its rings within the next 100 million years, which builds off previous observations from NASA’s Voyager 1 and 2.
The space missions that contributed the UV data used for this study came from NASA’s Hubble Space Telescope, NASA’s retired Cassini spacecraft, the European Space Agency’s retired International Ultraviolet Explorer mission, and NASA’s Voyager 1 and 2 spacecraft when they flew through the Saturn system in 1980 and 1981, respectively. This means the researchers used data from between 1980 and 2017, with scientists initially overlooking data exhibiting atmospheric UV surplus measured by Voyager 1 and 2, having interpreted it as noise, and with similar data being gathered by all the missions over the next 37 years.
The longstanding conundrum was trying to determine whether all this data from five space missions over the course of almost 40 years was accurate or deceptive, but Dr. Ben-Jaffel stepped up to the task and decided to use Hubble’s Space Telescope Imaging Spectrograph (STIS) to collect UV data from Saturn in 2017 and calibrate it against all the data back to 1980.
Composite image from three individual images of Saturn taken by Voyager 2 on July 12, 1981 through ultraviolet, violet, and green filters. (Credit: NASA/JPL)
Saturn’s southern hemisphere and bottom face of the rings taken by NASA’s Hubble in 2003. (Credit: NASA and E. Karkoschka (University of Arizona))
“When everything was calibrated, we saw clearly that the spectra are consistent across all the missions. This was possible because we have the same reference point, from Hubble, on the rate of transfer of energy from the atmosphere as measured over decades,” said Dr. Ben-Jaffel. “It was really a surprise for me. I just plotted the different light distribution data together, and then I realized, wow – it’s the same.”
In the end, Dr. Ben-Jaffel found the same level of UV radiation from all the data between all the space missions. This finding was assisted by examining our Sun’s seasonal effects on Saturn from the various solar cycles over the almost 40 years of data, as well.
“At any time, at any position on the planet, we can follow the UV level of radiation,” said Dr. Ben-Jaffel. “This points to the steady ‘ice rain’ from Saturn’s rings as the best explanation. We are just at the beginning of this ring characterization effect on the upper atmosphere of a planet. We eventually want to have a global approach that would yield a real signature about the atmospheres on distant worlds. One of the goals of this study is to see how we can apply it to planets orbiting other stars. Call it the search for ‘exo-rings.’”
What new discoveries will scientists make about Saturn’s rings in the coming years and decades, and could this be used to hunt for “exo-rings”? Only time will tell, and this is why we science!
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.
