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NRC’s adaptive optics help astronomers see better and farther into space – National Research Council Canada – Conseil national de recherches Canada

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Twinkling stars have enchanted humans since the dawn of time. But they make it hard for astronomers to get clear images of the skies. Great news: advanced technology developed by the National Research Council of Canada (NRC) takes the twinkle out, and changes the game for studying our universe.

Once the light from a star enters the earth’s atmosphere, it passes through several layers of air turbulence that appear to make the light flicker or twinkle. This effect also distorts images taken by telescopes on the ground. Fortunately, scientists can now remove that atmospheric disturbance with adaptive optics, clearing the air for those telescopes to take crisp, pure images.

Researchers at the NRC’s Herzberg Astronomy and Astrophysics Research Centre have developed an experimental adaptive optics system that is undergoing rigorous tests on their 1.2-metre McKellar Telescope in British Columbia. This project—Research, Experiment and Validation of Adaptive Optics with a Legacy Telescope (REVOLT)—uses advanced cameras, high-speed computers and bendable mirrors to correct the effects of atmospheric turbulence. With adaptive optics, the images produced by telescopes on earth can be as high-quality and high-resolution as they would be from telescopes in space above the atmosphere, and cost much less.

According to Dr. Jean-Pierre Véran, Adaptive Optics team leader at the Herzberg Astronomy and Astrophysics Research Centre, REVOLT has immense implications for larger optical telescopes now in place (up to 10 metres) and in development (up to 39 metres). “Time on these big telescopes around the world is in very high demand, so when they acquire new technology, they want proof that it has a very high level of maturity,” he says. “REVOLT serves as a test bench that allows us to validate new technologies on a small telescope in operational conditions.”

Image of the star Alpha Persei with the system off (left) and on (right) shows REVOLT improved the resolution by a factor of 5 and the sensitivity by a factor of almost 500.

He points out that the project, which took about 2 years to complete, was successfully tested on the McKellar Telescope for the first time in August 2022, with more observations planned for September. “This means we can see an object almost 500 times fainter with the same amount of observing time, which is an illustration of one of the key benefits of Adaptive Optics for large research telescopes,” says Dr. Kathryn Jackson, Adaptive Optics scientist at the Herzberg Astronomy and Astrophysics Research Centre. The research showed that REVOLT was able to efficiently correct the atmospheric turbulence, demonstrating that 2 novel technologies performed as expected when tested in operational conditions. These are the Herzberg Extensible Adaptive Real-Time Toolkit (HEART) and a new commercial high-speed camera called C-Blue One.

Real-time control platform and camera

HEART’s first client, the Gemini North Observatory in Hawaii, tasked the researchers to work with the Gemini North Adaptive Optics (GNAO) imager to fix the twinkle for the observatory’s massive telescope.

The instrument’s real-time controller (RTC) is based on HEART, created by the research centre’s multidisciplinary team. HEART’s layout, architecture and tools make it easy to adapt to and drive any adaptive optics system. The GNAO RTC acts as the brain of the system, which processes incoming natural and laser-guide star sensor signals and issues commands to the deformable mirrors.

“This system will be able to capture astronomical images with unprecedented resolution, sensitivity and contrast,” says Jennifer Dunn, head of the research centre’s Software Group. “Once installed, it will significantly increase the scientific productivity of Gemini.” HEART will also be deployed on several adaptive optics systems in observatories around the world.

An integral part of the platform is the new commercial C-Blue One camera by First Light Imaging. The REVOLT experiment was the first time this camera was used in an AO system on a telescope observing real astronomical objects. In REVOLT, this CMOS low-noise digital camera takes 1000 high-resolution images per second.

Putting it all together

The multidisciplinary REVOLT team includes engineers and scientists specializing in adaptive optics, software, high-precision opto-mechanics and electronics. They will also be working with other NRC research centres that will use the test bed starting this fall.

For example, the REVOLT system will be used to feed corrected starlight into an optical fibre, to enable an on-sky demonstration of a novel fibre-fed prototype instrument known as a spectral correlation sensor. This sensor, which was jointly developed by researchers at the Herzberg Astronomy and Astrophysics and Advanced Electronics and Photonics research centres, exploits the advantages of silicon photonics chip technology to produce an ultra-compact, lightweight astronomical instrument that will be used for high-sensitivity, real-time, remote gas detection in stellar and planetary atmospheres. This will be the first field test of this new instrument technology, using real operating conditions at a professional grade telescope.

Furthermore, the NRC’s Nanotechnology Research Centre will test-drive a new generation of low-voltage deformable mirrors (LVDM) on REVOLT. LVDM can correct distorted images from land-based telescopes and ground-to-space communications waves due to turbulence in the atmosphere. LVDM is key to integrate various components of a Micro-Electro-Mechanical System Deformable Mirror, including the mirror face sheet, the electromagnetic actuator, the circuits on a semiconductor wafer and the printed circuit board, all because of low driving voltage utilized by the electromagnetic force (known as the Lorentz force) from a powerful permanent magnet. LVDM is helping to compensate for atmospheric turbulence in real time with incredibly low power consumption, high mirror displacement, high fill factor of the reflective deformable mirror surface, and with a 1 millisecond response time.

REVOLT is instrumental in demonstrating novel technologies that are critical to the advancement of adaptive optics, which is key to progress in astronomy and physics, and in our understanding of how nature works. Adaptive optics also enables disruptive technologies used in many fields, including telecommunications, ophthalmology, microscopy and laser treatment of diseases.

“It has many long-term benefits for Canadians and other citizens of the world, and the faster we are able to develop these new technologies, the sooner we can effect important changes,” concludes Dr. Véran.

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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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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.

The Canadian Press. All rights reserved.

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