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Potential satellite collision shows need for active debris removal – SpaceNews

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WASHINGTON — Two decades-old defunct spacecraft are in danger of colliding Jan. 29, an event experts argue is more evidence of the need to clean up low Earth orbit.

LeoLabs, a California company that operates a network of ground-based radars that track objects in orbit, announced Jan. 27 that it had identified a potential conjunction, or close approach, between the Infrared Astronomical Satellite (IRAS) and the Gravity Gradient Stabilization Experiment (GGSE) 4 satellite in LEO. The company said there was an approximately 1-in-100 chance that the two satellites would collide at 6:39 p.m. Eastern Jan. 29 an altitude of about 900 kilometers, almost directly above the city of Pittsburgh.

LeoLabs, in an update Jan. 28, revised the probability of a collision downward, to about 1 in 1,000, estimating that the two spacecraft will pass between 13 and 87 meters of each other. Other sources have estimated similar probabilities of a collision between the two objects using other data, such as that from the catalog maintained by the U.S. Air Force.

Neither IRAS, launched in 1983, nor GGSE-4, launched in 1967, are operational today and have the ability to maneuver. While close approaches between debris are not uncommon, the circumstances of this event make it unusual and, to some orbital debris experts, worrying.

“This is a little bit unusual,” said Dan Oltrogge, director of the Center for Space Standards and Innovation at Analytical Graphics, Inc., in a Jan. 28 interview. The two spacecraft are in “counterrotating” orbits, meaning a collision would effectively be head-on, at an estimated relative velocity of 14.9 kilometers per second. That would maximize the energy of any collision.

Moreover, IRAS is a large satellite, with a mass of more than 1,000 kilograms. GGSE-4 — also known as POPPY-5B, a signals intelligence satellite — is much smaller, at 85 kilograms. However, it has a boom 18 meters long that will be perpendicular to the direction of motion. “In this case, that tends to maximize the collision potential,” Oltrogge said.

It may not be clear for hours after closest approach if the two satellites avoided a collision, depending on what assets are available to track them. Even if they miss, though, he said the conjunction should serve as a reminder of the hazards that other large objects, both satellites and upper stages, pose in Earth orbit, and the need to remove them.

“Even if these don’t hit, there will be others that will,” he said. “I think this can serve as a wakeup call for us to look at not only avoiding collisions with active satellites, but also remediating, figuring out how to remove debris in orbit.”

A paper that Oltrogge and others presented at the International Astronautical Congress in October 2019 discussed the risks of such collisions. They modeled the collision of two upper stages in orbit at 981 kilometers, concluding it could create between 3,375 and 12,860 objects at least 5 to 10 centimeters in size, as well as more than 200,000 additional debris objects at least 1 centimeter across dubbed “lethal nontrackable” because they are large enough to damage or destroy a satellite but too small to be tracked.

Another co-author of that paper was Darren McKnight of Centauri, who made similar arguments in a presentation at the Advanced Maui Optical and Space Surveillance Technologies conference in September. He noted that, in May, two rocket bodies that are part of a “cluster” of such objects at an altitude of 850 kilometers passed within 87 meters of each other. “They’re big yellow school buses with no driver,” he said. “If they collide, it would have doubled the catalog population in one event.”

“I would hope that we could take this, and other conjunction events and close approaches, to try and get another look at active debris removal and other remediation techniques,” Oltrogge said of this potential conjunction. “But time will tell.”

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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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