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Meteorite gouged huge Greenland crater 58 million years ago, study finds – Euronews

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By Will Dunham

WASHINGTON – An immense crater in northwestern Greenland, buried under a thick sheet of ice and first spotted in 2015, is much older than previously suspected – formed by a meteorite impact 58 million years ago, rather than 13,000 years ago as had been proposed.

Scientists said on Wednesday they used two different dating methods on sand and rock left over from the impact to determine when the crater – about 19 miles (31 km) wide – was formed. They found that the meteorite – roughly one to 1.25 miles (1.5-2 km) in diameter – struck Greenland about 8 million years after a larger asteroid impact at Mexico’s Yucatan Peninsula wiped out the dinosaurs.

The crater lies beneath Greenland’s Hiawatha Glacier, covered by an ice sheet six tenths of a mile (1 km) deep. It had remained undetected until airborne ice-penetrating radar data tipped off scientists about its existence.

It is one of Earth’s 25 largest-known impact craters. Over the eons, Earth has been hit by space rocks innumerable times, though gradual changes in the planet’s surface have erased or obscured many of the craters.

Greenland at the time – during the Paleocene Epoch – was not the icy place it is today, and instead was covered with temperate rain forests populated by a variety of trees and inhabited by some of the mammals that became Earth’s dominant land animals after the dinosaurs – aside from their bird descendants – went extinct.

The meteorite released millions of times more energy than an atomic bomb, leaving a crater big enough to swallow the city of Washington.

“The impact would have devastated the local region,” said Swedish Museum of Natural History geologist Gavin Kenny, lead author of the research published in the journal Science Advances http://www.science.org/doi/10.1126/sciadv.abm2434.

“The air blast from the impact would have knocked down most trees within tens to hundreds of kilometers, and the thermal blast from the impact would have ignited trees up to hundreds of kilometers from the site of impact, starting enormous forest fires,” Kenny added.

The impact also would have triggered regional seismic shaking while ash from the forest fires and dust and molten rock that had been violently ejected into the atmosphere would have rained down, yielding a thick blanket of debris, Kenny said.

As bad as it was, it did not approach the scale of calamity wrought by the asteroid – estimated at 7.5 miles (12 km) wide – that struck 66 million years ago, erasing three quarters of Earth’s species and initiating a global climate catastrophe.

“Whether the impact had a long-lasting effect on the global climate is currently unclear, but unlikely in my opinion,” said geology professor and study co-author Michael Storey of the Natural History Museum of Denmark. 

Some scientists had hypothesized that the impact occurred after the Greenland Ice Sheet formed 2.6 million years ago and perhaps even as recently as about 13,000 years ago to initiate a documented cold period.

The researchers used two dating methods based on radioactive decay – the transformation of atoms of one element into atoms of another element. Because the ice-encased crater is inaccessible, they tested sand from rocks superheated by the impact and minerals called shocked zircons contained in pebbles – all scooped up from a river carrying material from the crater out of the glacier. Both methods yielded the same age results.

“Thus, the impact did not happen – or cause a climate-change event – in the time of humans as had been proposed and speculated previously,” Kenny said.

“Impacts of this size occur only every few million years so we don’t need to be very worried about such an impact happening anytime soon,” Kenny added.

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A good day to die: doom for the dinosaurs came in springtime

Scientists count the world’s tree species (spoiler: it’s a bunch)

Older date for Ethiopian fossils sheds light on rise of Homo sapiens

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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.”

The Canadian Press. All rights reserved.

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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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