A team of scientists in Canada have found a Fast Radio Burst (FRB) that repeats every 16 days. This is in stark contrast to other FRBs, which are more sporadic. Some of those sporadic FRBs occur in clusters, and repeat irregularly, but FRBs with a regular, repeatable occurrence are rare.
A Fast Radio Burst is a pulse of radio emissions that lasts only milliseconds. The first one was discovered in 2007 by astrophysicist Duncan Lorimer and his student David Narkevic, and is called the Lorimer Burst. Since that time, many more have been discovered, but their origin is still unclear, though we know their source is extra-galactic.
The team of scientists have published a paper presenting their findings. It’s titled “Periodic activity from a fast radio burst source.” They’re working with data from CHIME, the Canadian Hydrogen Intensity Mapping Experiment.
CHIME is a radio telescope, but it’s an unusual one. Rather than a dish which can be aimed at targets, CHIME is stationary, and has no moving parts. It consists of four half-cylinders, and each half-cylinder holds 256 dual-polarized receivers. Together that’s 2048 signals received for processing. CHIME watches a vast, moving swathe of sky as the Earth rotates.
CHIME consists of four metal “half-pipes”, each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
The new burst is called FRB 180916.J0158+65, and it represents an unusual opportunity. Since most FRBs don’t repeat, there’s no way to do follow-up observations. But FRB 180916.J0158+65 repeats about every 16 days. There are about 10 other known FRBs that repeat, but they don’t repeat regularly.
In this case, the researchers were studying data from CHIME. Once they spotted this new FRB, they looked at past data, and found 400 observations of the new FRB. They determined that it repeats 16.35 days. The signals arrived about once every hour for a four day period, and then stop. Then about 12 days later they’d start up again.
Astronomers have been able to pinpoint the origin of the new FRB. It’s coming from an active star-forming region in a nearby massive spiral galaxy. It’s one of only four FRBs to have its source pinpointed like this, and of those four, it’s the only repeater.
Since astrophysicists still don’t know what creates FRBs, pinpointing their sources is a key part of understanding them. While this latest FRB is coming from a star-forming region in a spiral galaxy about 500 million light years away, other FRBs appear to have different sources. One, for instance, came from a low-metallicity irregular dwarf galaxy, indicating that there may be more than one source for FRBs.
But nobody really knows yet.
One hypothesized source of Fast Radio Bursts is magnetars, pulsars with extremely strong magnetic fields. In this illustration, magnetar’s crust is rupturing, causing a high-energy eruption. Image Credit: NASA’s Goddard Space Flight Center/S. Wiessinger
There are many theories of what could be creating FRBs, and mostly its speculative. But there are some constraints on those speculations.
Since FRBs only last for a few milliseconds, astrophysicists think there source might be small, something only a few hundred kilometers across. And since we detect them from such distant sources, their sources must be energetic.
Some think the FRBs may be connected to Gamma-Ray Bursts (GRBs). Or they might be created when massive objects collide, like neutron stars and black holes. Another possibility is magnetars, a type of neutron star with an extremely powerful magnetic field. Or maybe stellar flares. Some people, mostly not professionals, think these signals could come from an alien technological civilization.
An artist’s impression of a magnetar. Magnetars are one hypothesized source of Fast Radio Bursts. Credit: ESO/L. Calçada
There are more hypothesized sources, like extremely energetic supernovae, or pulsars collapsing due to dark matter. From there, the hypotheses get more and more exotic, like cosmic strings, explosive decays of axion mini-clusters, and pulsars that venture to close to supermassive black holes.
When there are that many candidate causes for a phenomenon, it means you don’t have much to go on.
Since FRB 180916.J0158+65 repeats, its source could be a stellar body in orbit around another body. In that scenario, the signal would be blocked by the other body in a regular periodic pattern. But that explanation only goes so far, and doesn’t suggest what the source is. In a press release, other possibilities are mentioned, including stellar winds. Those winds could alternately boost and block the signal. Or the source itself is a rotating body. Or some combination of factors could be responsible.
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For now the source is still a mystery. But the source has been located, and if the new FRB maintains its repetitive nature, future telescopes might be able to pinpoint the source with more precision. If and when that happens, we might get our answer.
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.
