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China's first lunar orbit docking: How to avoid a space crash – CGTN

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In one of the 11 steps to bring 2 kilograms of moon samples back to Earth, the ascender of China’s Chang’e-5 lunar probe has docked with the orbiter module and is ready to return.

Docking in space is in no way similar to how it happens in Japanese animes, wherein robots often speed up and rush into the action, even producing loud, metal clunking sound. In reality, the docking process is very gentle, achieved at an acceleration of only a thousandth of a rocket.

If a loud clunking sound is produced, that may mean something has been broken. What’s more, you can’t really hear the sound because sound in general cannot travel in the vacuum of space.

All in all, it’s a work of precision, instead of a collision.

How did the two parts “kiss” each other in space? Not long after the docking completed, the engineers at China Aerospace Science and Industry Corporation (COSIC) revealed the technologies they had developed for the Chang’e-5 mission.

Acceleration measurement system

Acceleration describes the change in speed. When a rocket was ignited, its acceleration surge. But when the ascender travels at a static speed in space, the acceleration is zero.

The tool used to measure acceleration is called accelerometer, which also exists in our smartphones to detect motion and orientation – yeah, the “auto rotate” feature.

The accelerometer used on Chang’e-5 is mostly the same as in its predecessors, with one important difference: Many crash cushions were added to reduce the impact when the ascender performs big movements like lifting off from the moon.

“Those dampers were installed in many places. It’s a bit like the corner cushion we stick on furniture,” said Fu Jibo, an engineering designer working for COSIC. “The problem is, we have to put them in the correct location, so the accelerometer won’t rotate after embracing impact.”

It took him and his team more than two months to do experiments and find the best locations. The test result was great because they can limit the rotation under one arc second – less than 0.0003 degrees.

Microwave radars

No, not the microwave oven we use at home. The radars used in the docking process happened to utilize the same kind of radiation as the home ovens do.

Radars are the eyes of the ascender-orbiter pair to “look” at each other. They are one of the four critical technologies used in the Chang’e-5 mission.

A set of radar consists of a microwave emitter and receiver. One is installed on the ascender and the other on the orbiter.

When the pair got close to each other, the radar was switched on to detect the distance between them.

“We have been used to do docking in the Earth orbit,” said Sun Wu, chief engineer of the radar. “But the Chang’e mission is much harder because it happens much farther away from the Earth.”

Satellite-based navigation like Beidou and GPS won’t work at such distance, so the radars are the only thing to depend on.

In addition, the radars were also used as a data transmitting device like the WiFi we use at home.

To make sure the radars work as intended, the engineers at COSIC carried out 15 simulations and took the interference of moon dust into consideration.

“We want to bring no pity or defect into the space,” said He Zhongqin, chief designer of the radar system.

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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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