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Dart: Mission to smack Dimorphos asteroid set for launch – BBC News

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NASA / JHUAPL / Steve Gribben

A spacecraft is set to launch and test technology that may one day be needed to tip a dangerous asteroid off course.

Nasa’s Dart mission will evaluate a longstanding proposal for neutralising a sizeable space rock headed for Earth.

The spacecraft will crash into an object called Dimorphos to see how much its speed and path can be altered.

If a chunk of cosmic debris measuring a few hundred metres across were to collide with our planet, it could unleash continent-wide devastation.

It’s the first attempt to deflect an asteroid for the purpose of learning how to protect Earth, though this particular asteroid presents no threat.

“Dart will only be changing the period of the orbit of Dimorphos by a tiny amount. And really that’s all that’s needed in the event that an asteroid is discovered well ahead of time,” said Kelly Fast, from Nasa’s planetary defense coordination office,

At 06:20 GMT on Wednesday, a Falcon 9 rocket carrying the Dart spacecraft will blast off from Vandenberg Space Force Base in California.

Asteroids are the left-over building blocks of the Solar System, with most posing no threat to our planet. But when a space rock’s path around the Sun crosses that of Earth so that the two objects intersect at the same time, a collision may occur.

The $325m (£240m) Dart mission will target a pair of asteroids that closely orbit each other – known as a binary. The larger of the two objects, called Didymos, measures around 780m across, while its smaller companion – Dimorphos – is around 160m wide.

Objects of Dimorphos’ size could explode with many times the energy of a typical nuclear bomb, devastating populated areas and causing tens of thousands of casualties. Asteroids with a diameter 300m and larger could cause continent-wide destruction, while those bigger than 1km would produce worldwide effects.

After Dart launches, it will first escape the Earth’s gravity, following its own orbit around the Sun. It will then intercept the binary as it approaches within 6.7 million miles of Earth in September 2022.

Dart will smash into the “moonlet” Dimorphos at a speed of around 15,000mph (6.6 km/s). This should change the speed of the object by a fraction of a millimetre per second – in turn altering its orbit around Didymos. It’s a very small shift, but it could be just enough to knock an object off a collision course with Earth.

“There are a lot more small asteroids than there are large ones and so the most likely asteroid threat we ever have to face – if we ever have to face one – is probably going to be from an asteroid around this size,” said Tom Statler, the mission’s program scientist at Nasa.

In 2005, Congress directed Nasa to discover and track 90% of near-Earth asteroids larger than 140m (460ft). No known asteroids in this category pose an immediate threat to Earth, but only an estimated 40% of those objects have actually been found.

Dart is carrying a camera called Draco that will provide images of both asteroids and help the spacecraft point itself in the correct direction to collide with Dimorphos.

About 10 days before Dart hits its target, the American spacecraft will deploy a small, Italian-built satellite called LiciaCube. The smaller craft will send back images of the impact, the plume of debris kicked up and the resulting crater.

The tiny change in Dimorphos’ path around Didymos will be measured by telescopes on Earth. Tom Statler commented: “What we really want to know is: did we really deflect the asteroid and how efficiently did we do it?”

A binary is the perfect natural laboratory for such a test. The impact should change Dimorphos’ orbit around Didymos by roughly 1%, a change that can be detected by ground telescopes in weeks or months.

NASA / JHUAPL / Ed Whitman

However, if Dart were to slam into a lone asteroid, its orbital period around the Sun would change by about 0.000006%, which would take many years to measure.

The binary is so small that, to even the most powerful telescopes, it appears as a single point of light. However, Dimorphos blocks some of Didymos’ reflected light as it passes in front, while the opposite occurs when the smaller object moves behind its bigger companion.

“We can measure the frequency of those dimmings,” explained Dart’s investigation lead Andy Rivkin, adding: “That’s how we know that Dimorphos goes around Didymos with a period of 11 hours, 55 minutes.”

After the impact, astronomers will take those measurements again. “They’ll happen a little bit more frequently – maybe it’ll be two every 11 hours 45 minutes, maybe it’ll be 11 hours, 20 minutes,” said Dr Rivkin, who is based at Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Laurel, Maryland.

He said there was a degree of uncertainty over how Dimorphos would respond to the impact, in part because its interior structure wasn’t known. If Dimorphos is relatively solid inside, rather than full of spaces, it might produce lots of debris – which would give the object an extra push.

Dart’s method for dealing with a hazardous asteroid is known as the kinetic impactor technique. However, there are other ideas, including moving the asteroid more slowly over time and even detonating a nuclear bomb – an option familiar from Hollywood movies such as Armageddon and Deep Impact.

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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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