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Astronomers detect another form of mysterious, repeating radio burst — it's probably not aliens – CBC.ca

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A team of scientists has discovered another piece of the puzzle that might shed more light on a mysterious astronomical phenomenon. 

Fast radio bursts, or FRBs, are powerful flashes of radio waves, lasting only a few milliseconds, that traverse the vast distance of space. The first one was discovered in 2007 after astronomers went through data collected in 2001. 

At first, most were one-offs — a flash and then they were gone. But in 2015 Paul Scholz, then an astronomer at McGill University, found one that repeated, though not with any regularity.

Now, a new discovery by a team of astronomers using the Canadian Hydrogen Intensity Mapping Experiment telescope (CHIME) at the Dominion Radio Astrophysical Observatory in Okanagan Falls, B.C., has made the first discovery of an FRB that repeats on a regular basis. It’s relatively close to Earth in astronomical terms: just 500 million light years away.

The discovery might help astronomers reveal what is exactly causing these immensely powerful bursts to help scientists better understand how the universe works. 

This new FRB, designated FRB180916.J0158+65, is the first to produce a periodic pattern. It begins to produce bursts within a four-day window followed by 12 days of silence, for a total period of 16 days. 

“We’ve been watching this thing for 500 days, so we’ve seen 20 or 30 cycles actually of the 16-day period, and it really is like clockwork,” said Canadian Kiyoshi Masui, an assistant professor of physics at MIT’s Kavli Institute for Astrophysics and Space Research and co-author of the paper published in Nature this week. We only see bursts when we expect to see a burst.”

Watch: New radio telescope unveiled in B.C.

Scientists hope CHIME, Canada’s largest radio telescope, will be a major step forward in uncovering the secrets of the universe 2:04

Masui said several hundred FRBs have been observed by radio telescopes since the first discovery in 2007, with roughly 20 repeating sources. But until now, there’s never been a pattern to any of them. And that limits astronomers’ understanding of what is actually causing them.

And yes, there’s even been speculation that these signals could be coming from an alien civilization, though others believe it’s unlikely

The leading hypothesis is that they’re being created by a magnetar, an extremely dense star with a magnetic field that is trillions of times more powerful than that of the sun.

A galactic explosion

Before the new discovery, all the FRBs that have been detected have come from galaxies billions of light years away. But recent bursts from a magnetar in our own galaxy is strengthening the case for FRBs originating from these small but incredibly dense stars. 

In a paper published on the pre-print site arXiv.org in May, astronomers reported a strong radio outburst coming from a magnetar called SGR 1935+2154.

Astronomers are, however, hesitant to say that this burst is definitive proof of the FRB source theory.

“One thing that makes the burst from the galactic magnetar different is that it’s still not as bright  as the faintest FRBs we detect,” said Scholz, co-author of the Nature paper, who is now an astronomer at the University of Toronto’s Dunlap Institute for Astronomy and Astrophysics. “It’s about 10 to 100 times fainter or less energetic than the FRBs we get … It’s getting close, so it’s tempting to connect these two phenomena together.”

The CHIME/FRB Collaboration, which involves astronomers from around the world though most are Canadian, is constantly searching for these FRBs using the telescope. Since its “first light” on Sept. 7, 2017 — which you can think of as a newborn baby opening his or her eyes for the first time — the telescope has already detected hundreds of FRBs, though astronomers won’t say exactly how many are discovered on a daily basis. 

The CHIME telescope, which looks more like a half-pipe than a traditional telescope, is able to search the entire sky for these FRBs, increasing the chances of detection. 

Astronomers using the CHIME telescope in B.C., seen here, have tracked two repeating fast radio bursts to different galaxies outside the Milky Way. (CHIME)

While finding only one periodic FRB may seem like an anomaly, Masui said that, when it comes to astrophysics, most things are periodic.

“We see stars orbiting black holes; we see all kinds of things that have periodic behaviour in astrophysics,” he said. “People have been looking for exactly this phenomena ever since FRBs were discovered. We had to wait until now until we had a source that was bright enough and prolific enough to actually see it.”

Astronomers are hopeful that more of these periodic bursts will be found with the collaboration.

Masui is particularly interested in what these bursts can also reveal when it comes to the bigger picture, as the radio waves travel through intergalactic gas and dust.

“It’s not only the astrophysics of this phenomenon, but what they can tell us about the universe as a whole,” Masui said.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

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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