The cosmos is the stage for a variety of giant explosions. These include stellar flares, where stars suddenly release magnetic energy; and neutron star mergers, where two dense stars collide together. But one class of explosions outshines the rest: gamma ray bursts are the most energetic explosions seen in the universe.
Gamma rays are one of the most energetic forms of light, and gamma ray bursts release almost unimaginable quantities of them. First discovered during the cold war—by military satellites searching for the signs of nuclear tests in the upper atmosphere—gamma ray bursts are now thought to be caused by massive stars undergoing huge explosions when they run out of fuel. These events are rare, but so energetic they can be seen in galaxies many billions of light years away.
Recently, astronomers thought they had seen evidence for one of these explosions from the most distant galaxy every seen. But a recently published paper casts doubt on these claims, suggesting it might have been caused by a more mundane source much closer to home.
Gamma ray bursts
No gamma ray bursts have been documented in our galaxy yet, which may not be a bad thing. A gamma ray burst pointed directly at the Earth would probably lead to a mass extinction event, and the end of civilisation as we know it. Undocumented events may in fact already have caused mass extinction events in Earth’s history.
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Gamma ray bursts have been seen far away, however. The paper suggesting researchers had discovered a new gamma ray burst in the most distant known galaxy was published in 2020. Using the Keck telescope on Mauna Kea, Hawaii, the researchers observed strips of the sky, and happened to see a bright flash, just a few seconds long, in one of their exposures.
By modeling the duration and brightness of the flash, they ruled out the possibility that it was a natural or human-made satellite close to home. They also ruled out a number of other astronomical explanations, and concluded that the most likely explanation was, indeed, a gamma ray burst.
What was so unique about this discovery was that the team pinpointed the direction of the event and found it was coming from the same area as a galaxy known as GN-z11, which just so happens to be the most distant and oldest galaxy we’ve yet discovered.
Was this an incredible cosmic coincidence? Or was this a sign that gamma ray bursts were more common in the very early universe, just 400 million years after the big bang? The latter conclusion would have big implications for our understanding of how stars and galaxies form in the early universe, and led to a lot of excitement among astronomers.
But unease about the conclusions of the group surfaced, with some arguing it was much more likely that the flash was from an object within our solar system, which could be a natural (such as a moon) or artificial satellite. In another paper, a different team suggested the most likely explanation was a reflection from a human-made satellite. The original authors followed up on these claims, doubling down on their gamma ray burst interpretation, but the chorus of doubters was only getting louder.
The Roman Baranowski Telescope/Poznań Spectroscopic Telescope used to confirm the man-made nature of the flash, and the position of GN-z11. Credit: Krzysztof Kamiński, Adam Mickiewicz University in Poznań
Space junk
Now, the controversy has taken another turn, with a new paper recently published in Nature. The authors of this paper suggest the purported gamma-ray burst was in fact a flash caused by a human-made satellite after all. The researchers used a public space-track website to search for possible human satellite interference in the direction and at the time of the flash detection.
Around the time that the original team were studying the sky, a Russian proton rocket reached low Earth orbit and released its upper stages (dubbed Breeze-M), which then became space junk, orbiting the Earth. By looking at the orbit of the space debris and matching with the observations taken in the original study, the new team found the flash could be simply explained by the upper stage falling past the part of the sky the telescope was observing.
The proton rocket has been in operation since the 1960s, and it’s not the only time one of its Breeze-M upper stages has been in the news. In 2013 an explosion scattered huge amounts of debris into near Earth orbit, and left NASA scrambling to assess whether it would pose a danger to the International Space Station.
While this particular incident was perhaps particularly unlucky, with increasing amounts of junk in space, and the launching of large constellations of satellites by the private company SpaceX and others in the coming years, it highlights the increasing difficulties astronomers face observing from the Earth’s surface.
Better databases of satellites and space debris will help avoid these kinds of misidentifications. But the increasing light pollution from satellite constellations threatens the ability of telescopes on the ground to even see clearly enough to do world-leading science.
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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.
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.
