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Radio telescopes still operate under wartime conditions | Life | pentictonherald.ca – pentictonherald.ca

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Three times a day a measurement is transmitted from the National Research Council’s Dominion Radio Astrophysical Observatory to a list of recipients around the world.

Some use it directly; others archive it and make it available on their websites, along with other data.

The measurements are made using two small radio telescopes, referred to as “flux monitors.” The data consists of measurements of the intensity of solar radio emission at a wavelength at 10.7 centimetres. It is used by those involved in activities where, one way or another, they are affected by what the sun is up to. These include communications services, space mission managers and various infrastructural services.

The data are known as “The 10.7 cm solar radio flux”, or simply, “F10.7.” This service has its roots in the Second World War.

In 1942, anti-aircraft radars which were sweeping the sky over Britain, searching for raiders, suddenly became unusable. Huge signals swamped any potential echoes. The display screens, which should have shown radar echoes, were filled with random dots and speckles.

This stuff is now referred to as “snow.” The radars were being jammed. The first fear was that Britain’s anti-aircraft defences were being affected by some secret weapon.

Then, one of the engineers shut off the transmitter on one of the radars, and waved the antenna around while looking at the display screen. Those jamming signals were coming from the sun. It was a relief to know that no secret weapon was involved, but since every time the sun did whatever it was doing, air defences were degraded; information about solar “attacks” was kept secret until after the war.

During that same war, warships at sea used their radars to sweep the horizon for any possible enemy ships. The operators soon noticed that when the radar antenna was pointed at the rising or setting sun, any echoes from that direction were swamped by the same sort of “snow.”

Since this phenomenon could be used by potential attackers, this too was kept as quiet as possible.

The Second World War was a high-tech war. It saw an explosion in the use of radar systems and advanced communication devices, along with efforts at making equipment to jam or spoof the enemy’s radars and communication devices.

When the war ended there were piles of this advanced electronics that were no longer needed.

Naturally occurring radio emissions from the Milky Way had been discovered in the 1930s, launching the embryo science of radio astronomy. The availability of unwanted military antennas and receiving systems provided a gold mine for making radio telescopes.

During the war, the National Research Council was a centre for the development of radar systems. After hostilities ended, the NRC scientists used bits of those radar systems to make Canada’s first radio telescope. They pointed the instrument at various objects in the sky, but the only thing they could detect was the sun, so they decided to accurately measure these solar radio emissions and how they varied.

Early in the war, Britain shared its military secrets with the United States and Canada. These included the resonant cavity magnetron. This device could generate high transmitter powers at centimetre wavelengths.

This was particularly needed for airborne radar systems; short wavelengths mean smaller antennas can be used. It is hard to accommodate large antennas on planes. The magnetrons operated at a wavelength of around 10.7 cm, so the radars did too.

So therefore did the NRC’s radio telescope. It turned out that measurements of solar radio emissions at this wavelength were a good indicator of the whole range of solar activity,

Which is why this service has continued to the present day.

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Venus is low in the dawn glow. To its right, lie Mars and Jupiter, close together, then Saturn. The moon will reach first quarter on Tuesday, and be full on June 14.

Ken Tapping is an astronomer with the National Research Council’s Dominion Radio Astrophysical Observatory, near Penticton

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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.”

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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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