Webb Telescope Brings a Star Into Focus as It Completes ‘Image Stacking’ Alignment Phase - Gizmodo | Canada News Media
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Webb Telescope Brings a Star Into Focus as It Completes ‘Image Stacking’ Alignment Phase – Gizmodo

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This simple composite image of a distant star represents a big step in Webb’s alignment process.
Image: NASA/STScI

The Webb telescope has completed the third stage in aligning its mirrors, a crucial process for getting state-of-the-art imagery out of this $10 billion space telescope. The feat comes right on time as the telescope heads into the second month of its three-month alignment period.

Since Webb arrived at its observation point in space, a place called L2, NASA team members have worked furiously to get the telescope ready to start doing science. That process has meant using one star, HD 84406, as a guidepost for aligning the 18 primary mirrors.

Engineers have brought 18 dots of starlight into a coherent pattern.
Image: NASA/STScI/J. DePasquale

The telescope fully deployed its mirrors in late January, saw its first light on February 4, and even snapped a sort-of selfie on February 11. The ultimate goal is to get the mirrors to match each other to about 50 nanometers, or 50 billionths of a meter. As Alise Fisher put it in a recent NASA blog, “if the Webb primary mirror were the size of the United States, each segment would be the size of Texas, and the team would need to line the height of those Texas-sized segments up with each other to an accuracy of about 1.5 inches.” Tweaks to the mirrors’ orientations are being made by humans here on Earth, a million miles from the telescope.

On February 18, the mirrors aligned enough to organize the 18 dots of light picked up by each of the 18 primary mirrors. The next step was to focus those 18 views of the same star into one point—literally by stacking the images on top of one another. That’s now done, as the image stacking alignment phase was completed February 25, three days ahead of schedule. HD 84406 as seen by Webb is now a single point of light, as it should be.

“We still have work to do, but we are increasingly pleased with the results we’re seeing,” said Lee Feinberg, optical telescope element manager for Webb at NASA’s Goddard Space Flight Center, in an agency release. “Years of planning and testing are paying dividends, and the team could not be more excited to see what the next few weeks and months bring.”

An artist’s illustration of the Webb telescope in space; its primary mirror is the gold disk.
Illustration: NASA GSFC/CIL/Adriana Manrique Gutierrez

The mirrors are still functioning as single instruments, though, rather than one big telescope they need to be. Fine-tuning alignments are necessary. The fourth phase of mirror alignment, called coarse phasing, will now begin. That process involves pairing 20 different mirror segments to take in light together; the team can use those results to detect where differences in the segments’ heights are reducing the image sharpness.

Coarse phasing will take place in the next several weeks, after which will come fine phasing, telescope alignment across the rest of Webb’s instruments (right now the team is just tinkering with the primary mirror) and, at last, final corrections. More details of the alignment phases can be read about here.

Webb will expand our knowledge of the early universe, galaxies, and exoplanets, as well as some objects within our solar system. The telescope is not replacing the veteran Hubble Space Telescope; it will observe in the infrared and near-infrared wavelengths, while Hubble primarily works in ultraviolet and visible light.

But Hubble launched back in 1990. Webb will peer into the cosmos alongside its predecessor, but it will look further back in time than any device before it, with technology that wasn’t possible 30 years ago.

A fully aligned, scientifically operational Webb is still some ways away—the ballpark estimate is mid-summer 2022—but the fact that nothing has gone wrong yet is a testament to the hours and effort invested by the scientists and engineers eager to give the world a whole new look at the ancient universe.

More: Webb Space Telescope Captures Selfie as It Aligns Its Gold Mirrors

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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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.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

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.

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.

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