Astronomers Just Found an Extremely Rare 'Ring of Fire' Galaxy in The Early Universe - ScienceAlert | Canada News Media
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Astronomers Just Found an Extremely Rare 'Ring of Fire' Galaxy in The Early Universe – ScienceAlert

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In the early days of the Universe, 10.8 billion years ago, astronomers have just found a galaxy wearing the battlescars of a cosmic brawl. It’s not a blob or disc of stars, like most galaxies, but a giant doughnut – with a huge hole punched right through its centre.

This classifies it as a rare type of galaxy known as a ring galaxy, and it’s rare even among that type – its shape forged not by internal processes, but a collision that saw its core stripped away as the other galaxy passed through.

The galaxy is called R5519, and it’s the first collisional ring galaxy ever found more than a few hundred light-years away – which makes it the only known such object in the early Universe.

“It is a very curious object that we’ve never seen before,” said astronomer Tiantian Yuan of the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) in Australia.

“It looks strange and familiar at the same time.”

The outer edge of R5519’s ring is pretty large, around 42,400 light-years across (on average). The hole punched through the middle is about 17,612 light-years across, with no detectable trace of the star-packed bulge that normally fills a galactic centre.

And there are clues that hint at a violent past.

Some ring galaxies seem to have had relatively peaceful formations, produced by such processes as orbital resonance or the accretion of material from another nearby galaxy.

But the former usually occurs in barred galaxies, and no such bar was observed in R5519; the accretion process shouldn’t disrupt the core, as seen in galaxies such as NGC 7742 and Hoag’s Object.

In addition, R5519 exhibits a high rate of star formation in its ring – around 80 solar masses’ worth of new stars are born every year. This is suggestive of a gravitational disruption – by, say, another galaxy punching through R5519, sending density waves propagating radially outwards.

As these waves push and condense the gas and dust in the galaxy, it triggers star formation by facilitating the gravitational collapse of clumps of dust that turn into baby stars.

(James Josephides/Swinburne Astronomy Productions)

In the local Universe, ring galaxies of this type are extremely rare – 1,000 times rarer than ring galaxies formed by less violent processes. The discovery of R5519 suggests, the researchers said, that collisional ring galaxies were as rare in the early Universe as they are in later times.

But it also offers an opportunity to study the formation of disc galaxies like the Milky Way – because in order to form a ring, simulations suggest the galaxy needed to be a thin disc before being punched through.

We didn’t think thin disc galaxies formed in the early Universe – most of the galaxies we’ve found are disordered hot messes, with blobby shapes and stars orbiting in all directions. Nice, orderly discs don’t start appearing until around 4 to 6 billion years after the Big Bang, which took place around 13.8 billion years ago.

Last week, astronomers revealed they’d identified a disc galaxy 12.5 billion light-years away, which was pretty mind-blowing. Now the discovery of R5519 10.8 billion light-years away seems to support the idea that discs weren’t that rare in the early Universe after all.

“The thin disc is the defining component of spiral galaxies: before it assembled, the galaxies were in a disorderly state, not yet recognisable as spiral galaxies,” said astronomer Kenneth Freeman of the Australian National University in Australia.

“In the case of this ring galaxy, we are looking back into the early Universe by 11 billion years, into a time when thin disks were only just assembling. For comparison, the thin disc of our Milky Way began to come together only about 9 billion years ago.

This discovery is an indication that disc assembly in spiral galaxies occurred over a more extended period than previously thought.”

The research has been published in Nature Astronomy.

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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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.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

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.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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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.”

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B.C. sets up a panel on bear deaths, will review conservation officer training

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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.

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