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Space scientists have big plans to avert an asteroid apocalypse

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Despite what you may have read, a 1,500-foot-wide asteroid named Bennu is not going to devastate our planet on Sept. 25, 2135. Brent Barbee, an expert on space hazards at NASA’s Goddard Space Flight Center, is clear on that point: “It’ll only closely approach Earth, not impact Earth,” he says. It should miss us by at least 65,000 miles.

But Barbee is also clear that if Bennu were to hit us, the consequences would be ugly. The 40-million-ton space rock would unleash a force equal to 80,000 atomic bombs like the one dropped on Hiroshima, enough to flatten buildings for dozens of miles in all directions. And while Bennu is the most dangerous asteroid on the planetary science watch list, 1,894 others are currently listed as “potentially hazardous objects.”

To size up the risk, NASA is sending a spacecraft called OSIRIS-REx to explore Bennu. The probe, shaped like an eight-foot cube with solar-panel wings, launched in September 2016 and will arrive at the space rock this August. When it does, it will nestle up to Bennu, testing rendezvous and landing techniques and collecting a surface sample to investigate the composition of such asteroids.

 This illustration provided by NASA depicts the OSIRIS-REx spacecraft and the Earth. Goddard Space Flight Center / NASA via AP

Meanwhile, Barbee has been leading a study of what it would take to protect our planet if Bennu — or another object like it — were on track for a full-on impact with Earth. The team presented its findings last month, and outlined a concept for a Hypervelocity Asteroid Mitigation Mission for Emergency Response.

HAMMER would be like a planetary defense shield: a fleet of spacecraft that would either bash directly into a dangerous asteroid or set off nuclear charges to deflect it. Barbee calls the HAMMER study “the first steps towards designing spacecraft systems for asteroid deflection.”

The first steps, but hardly the last.

Taking a shot at a double asteroid

In fact, the next step in planetary defense is already underway at Johns Hopkins University’s Applied Physics Lab. There, a team is developing a mission called the Double Asteroid Redirection Test, or DART, which is scheduled to launch around 2020. It’s the first real-world embodiment of the HAMMER concept.

The 1,100-pound DART craft has thrusters, a camera, navigation software, and that’s about it. Its design can be simple because its job is simple: find an asteroid and fly into it at full speed. Such a device is technically known as a kinetic impactor, but you can think of it as a battering ram in space.

“We think we understand the physics of asteroid deflection in theory, but we’ve never performed an experiment at the right scale,” says the Applied Physics Lab’s Andy Rivkin, lead investigator for the DART mission. “This is a dress rehearsal for a kinetic impactor-style of asteroid deflection.”

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The target set to be rammed is a double asteroid named Didymos. DART will go after the smaller of the two nearby space rocks, a 500-foot-wide rock nicknamed Didymoon. When the spacecraft reaches Didymoon, it will smash into it at 13,000 miles per hour. After the collision, DART will be destroyed but astronomers on Earth will watch to see exactly how Didymoon is changed and moved by the impact.

The DART data will be especially useful, Rivkin says, because Didymoon is believed to be what planetary scientists term a “rubble pile” — more an assemblage of small rocks than a single big one. It’s hard to know how such objects will react to a directed impact without running the experiment.

“DART will also be the first planned visit to a binary asteroid,” Rivkin says. Deflecting a double asteroid will be more complicated than dealing with a single incoming body. Soon we’ll know more about how to do it.

To nuke or not to nuke?

If a 500-foot-wide asteroid like Didymoon were on a collision course with Earth, Rivkin estimates that two or three DART-like battering rams could be enough to shove it aside — provided we had several years of advance warning. If we had to act quickly to deflect an incoming space rock, we would need a lot more force to avert a collision.

“The very best thing that can be done to prepare for the potential impact of any-sized asteroid is to find it as far ahead of the impact day as our capabilities allow,” says Lindley Johnson, NASA’s planetary defense officer.

 This artist’s rendering made available by NASA in July 2016 shows the mapping of the near-Earth asteroid Bennu by the OSIRIS-REx spacecraft. NASA/Goddard / University of Arizona via AP

Johnson oversees the Planetary Defense Coordination Office, which coordinates the monitoring of hazardous space objects. If a truly high-risk asteroid turns up, his office will work with other federal agencies to develop a response, perhaps along the lines of HAMMER.

The more immediate problem is early detection. There are a lot of potentially hazardous objects around, and simply finding them isn’t easy.

Johnson cites the daunting NASA estimates: There are roughly 25,000 Didymoon-scale asteroids, 230,000 asteroids in the 150-foot range, and millions more of diameters of 100 feet or less. So far, astronomers believe they’ve found about two-thirds of the large ones, 5 percent of the medium ones, and essentially none of the small fry.

Even the little ones could pack a mighty punch. If a mansion-size stone were to hit Earth over open ocean or remote countryside, it might cause little damage, Johnson says. If it struck a city or even near one, however, it would bring widespread death and destruction. And smaller rocks are generally unseen until they are right upon us.

In short-warning scenarios, kinetic impactors like DART would not be enough. Therefore, the HAMMER study explored the use of nuclear warheads, just as in movies like “Armageddon.” Nukes pack a bigger wallop and allow more precision, since we can adjust exactly how close they are to the asteroid when they explode.

For obvious political reasons, nobody is about to conduct a nuclear test strike on an asteroid. But OSIRIS-REx and DART will vastly increase the storehouse of data needed to turn the HAMMER studies into a real mission (even a nuclear one), if and when the need arises. After a long period of stinginess, Congress is also allotting more funding for asteroid surveys, increasing the likelihood that we’ll have enough warning to make nukes unnecessary anyway.

It seems that the world is finally embracing an argument that planetary-defense advocates like Rivkin have been making for years: “The asteroid threat is unique. It’s the only natural disaster that can be predicted and averted.”

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Taiwan invasion unlikely for now – but there are other ways China can turn the screw | World News

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The good news is that there are only five months when weather conditions are good enough to mount an invasion of Taiwan, according to Ian Easton, the author of The Chinese Invasion Threat. 

The bad news is that two of them are April and May.

So when Taiwan reported that 25 Chinese air force aircraft, including nuclear-capable bombers, entered its air defence identification zone (ADIZ) this week, fears of attack are front of mind.

It was the largest incursion by the Chinese military to date.

US Admiral Philip Davidson – Washington’s top military officer in the Asia-Pacific region – recently said he was worried China could invade Taiwan in the next six years.

Chiu Kuo-cheng, Taiwan’s new defence minister, responded: “His evaluation says six years, but my concerns include six hours.”

The foreign minister, Joseph Wu, said this month that in the event of an attack Taiwan would fight “to the very last day”.

The famous Taipei 101 in the capital
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It’s unclear how far the US would go if the threat to Taiwan reaches a new level

There is belligerence from the Chinese side. A defence ministry spokesperson said that a declaration by Taiwan of independence “means war”.

Hu Xijin, the editor of a nationalistic Chinese tabloid, said that the Chinese military could fly directly over the island of Taiwan itself, and if Taiwan fired at those planes, China would attack.

Hu’s attention-seeking provocations should always be taken with a pinch of salt but they show how the conversation around Taiwan is evolving.

But although the intensity is increasing, in many ways we are still in the status quo that has existed for decades.

China’s constitution, adopted in 1949, says Taiwan is part of its “sacred territory” and details the “inviolable duty” of “reunifying the motherland”.

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On the question of “Taiwan independence”, China as far back as 2005 passed a law that formally authorised military force if Taiwan was “separated” from China.

Taiwan has its own constitution and a highly functioning democracy – rated above Japan and South Korea by the Economist Intelligence Unit.

The election of President Tsai Ing-wen in 2016 led to an escalation in pressure from China. What we’re seeing now is best viewed as the latest development in that continuous period.

A pilot prepares to take off on a F-CK-1 Ching-kuo IDF at an Air Force base in Tainan
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Taiwan spent $900m scrambling jets to intercept Chinese planes last year

And as China has increased its attrition strategy, the US has increased its ties with the island, which in turn leads to more Chinese pressure.

That pressure is designed to take a psychological and logistical toll on Taiwan.

In 2020, Taiwan spent some $900m scrambling fighters to meet Chinese sorties and said it would no longer dispatch jets to meet every incursion, instead tracking Chinese aircraft with land-based missiles. Expect that pressure to continue.

But a full-scale invasion by China remains unlikely in the short term. That would require a massive build up of forces, easily detectable by US and Taiwanese monitoring.

There are options short of invasion that are still worrying.

China could blockade the island economically, or seize some of its outlying territory. The Kinmen Islands, administered by Taiwan, are barely a mile from China.

Any such move would be a test of the US resolve to defend Taiwan, perhaps analogous to Russia’s seizing of the Crimean Peninsula.

Would an aggressive Chinese move, short of full invasion, prompt the US to respond militarily?

Right now, no one knows. That means it would be hugely destabilising.

For all the pressures of the current moment, it at least fits a known, established pattern – and is far preferable to an escalation, the consequences of which would be difficult to predict.

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COVID-19: World Health Organisation calls for ban on sale of live wild mammals in food markets | World News

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The sale of live wild mammals at food markets should be suspended as an emergency measure, the World Health Organisation has said.

The statement comes after a WHO team visited Wuhan in China to investigate the origins of COVID-19.

The most likely scenario is that the virus originated in bats, was spread to another unidentified animal, and then passed on to humans, a WHO report said in March.

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The organisation said in a separate report on Tuesday that animals, “particularly wild animals”, are the source of more than 70% of emerging infectious diseases in humans.

They added many of these are caused by novel viruses – a virus that has not previously been recorded.

The report states: “Wild mammals, in particular, pose a risk for the emergence of new diseases. They come into markets without any way to check if they carry dangerous viruses.

“There is a risk of direct transmission to humans from coming into contact with the saliva, blood, urine, mucus, faeces, or other body fluids of an infected animal, and an additional risk of picking up the infection from contact with areas where animals are housed in markets or objects or surfaces that could have been contaminated with such viruses.”

The WHO said “traditional markets play a central role in providing food and livelihoods ” around the world.

It added that banning the sale of live wild animals would help to protect the health of both shoppers and workers.

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WHO: Lab leak COVID origin ‘unlikely’

The closest-related viruses to COVID-19 have been found in bats in southwest China.

The intermediate host is more elusive: mink, pangolins, rabbits, raccoon dogs and domesticated cats have all been cited as a possibility.

The WHO team said that a theory the virus was leaked from a lab was “extremely unlikely” but it has not been ruled out.

The call for a ban of the sale of wild animals comes as the the WHO said the global coronavirus pandemic is at a “critical point”.

It added that people need a “reality check” as restrictions are eased.

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Dr Maria van Kerkhove, head of the WHO’s technical response, told a news conference vaccinations alone are not enough to combat COVID-19.

Coronavirus restrictions were eased in parts of the UK on Monday, with shoppers returning to high streets and drinkers visiting pub gardens in England, and non-essential retailers reopening in Wales.

Dr van Kerkhove, speaking on Monday afternoon, urged caution, saying: “We need headlines around these public health and social measures, we need headlines around the tools that we have right now that can prevent infections and save lives.

“We are in a critical point of the pandemic right now, the trajectory of this pandemic is growing.”

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Facebook takes down official page for French town called Bitche | Science & Tech News

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Facebook has been criticised after taking down the official page for the French town of Bitche.

Local broadcaster Radio Melodie reported that the page was taken down, forcing the municipal communications officer to create a new one under another name.

Ms Valerie Degouy said the new page was named after the town’s post code, Mairie 57230, as reported by Politico.

Ms Degouy said: “I tried to reach out to Facebook in every possible way, through different forms, but there’s nothing [I could] do,” she said, adding she had “already had issues when I first created the page”.

Another of the commune’s towns, Rohrbach-les-Bitches, renamed its page Ville de Rohrbach out of caution.

In a post explaining the change, the account holder said: “Far from us the idea of denying the name of our beautiful village… [but] Facebook seems to be hunting the term associated with Rohrbach…

“We let you imagine the reason,” they added with a winking and laughing emoji.

As Politico reports, this is not the first time that the town’s name has caused upset for Americans.

Back in 1881, the US embassy was located on the Place de Bitche in Paris, named in honour of the town.

The then ambassador, Levi Parsons Morton, complained about the name as it appeared to be embarrassing on the embassy’s letterhead and Parisian authorities renamed the square Place des Etats-Unis.

A spokesperson for Facebook confirmed to Sky News that the page was removed in error, and had since been “swiftly restored this morning, when we because aware of the issue”.

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