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NASA launches first ever asteroid deflection mission

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Scientists including Stephen Hawking have described impact events as among the greatest threats facing humanity – and even if the planetary defence mission proves successful, huge questions about our future readiness will remain.

A spacecraft has been launched from California this morning carrying with it humanity’s greatest hopes of being able to protect our planet from a cataclysmic asteroid impact.

Fortunately the DART (Double Asteroid Redirection Test) mission is only a test, and if anything goes wrong before it intercepts its target next September, then Earth won’t suffer as a result.

But the stakes are high. Scientists including Stephen Hawking have described impact events as among the greatest threats facing humanity – and even if the DART planetary defence mission proves successful, huge questions about our future readiness will remain.

The DART spacecraft's collision will be observed by the LICIACube satellite
Image:The DART spacecraft’s collision will be observed by the LICIACube satellite. Pic: NASA

DART launched on top of a SpaceX Falcon 9 rocket at the Vandenberg Space Force base in California.

Roughly the size of a small car, the spacecraft has been developed by NASA and the Johns Hopkins Applied Physics Laboratory to demonstrate for the first time the “kinetic impactor technology” using a direct hit on an asteroid to adjust its speed and path.Advertisement

A small LICIACube satellite developed by the Italian space agency will travel alongside it to observe the collision which will take place when DART and its target asteroid are within 11 million kilometres of Earth, enabling ground-based telescopes to measure the impact too.

DART is targeting a near-Earth double asteroid known as Didymos and Dimorphos, with the latter being a “moonlet” estimated to be about 160 metres in size – a good test object, but not one that is actually expected to collide with Earth.

It will hit Dimorphos at a speed of roughly 6.6 kilometres per second and, in doing so, shorten its orbit about Didymos – proving that a kinetic impact can change an asteroid’s trajectory.

This nudge technique is preferred to blowing asteroids apart in the style of the film Armageddon, because the fragments from such an explosion could continue to imperil the planet.

A study from researchers at Johns Hopkins University in the US published in 2019 warned that for objects large enough to be targeted it was likely the blasted away fragments would reform under gravity.

Illustration of the DART spacecraft with the Roll Out Solar Arrays extended. Image credit: NASA
Image:The DART spacecraft is just the size of a small car, not including its solar arrays. Pic: NASA

How important is the mission?

The good news is that scientists are completely confident that no asteroids larger than 1km will strike our planet within the next century – the maximum period we can map out their movements for due to the unpredictability of dynamic systems.

What’s also good is that even among much smaller asteroids, ones larger than just 140 metres, there are no known objects that have a significant chance of striking Earth within the next 100 years too.

The bad news is that only 40% of these asteroids have been found, and the worse news is that asteroids can be much smaller than 140m and still cause significant damage to regions or cities.

Humanity’s ability to detect asteroids before they impact the planet is still in its infancy, in part because of limits set by the laws of physics – our ability to survey asteroids in the dark of space in our solar system depends on them reflecting light towards us, and that depends on direction of their approach relative to the sun and the phase of the moon.

There have been more than 1,200 impacts of asteroids larger than a metre in size since 1988 and of those impacts humanity has only predicted five in advance – less than 0.42% – and even those predictions came with just hours to spare.

This timeline offers much less wriggle-room than the five years between the DART mission getting approval at NASA and its scheduled rendezvous with Dimorphos next year.

Never mind deflecting an asteroid off-course, hours wouldn’t even offer enough time to evacuate a town.

But astronomers hope and expect that new technologies and monitoring systems will improve our ability to make these predictions in the future – giving us more time – and the DART mission is just the first step in us proving that there is something we can do about it when we know something is coming.

This video grab from YouTube footage shows a meteor streaking across the sky in the Chelyabinsk region of central Russia.
Image:This video grab from YouTube footage shows the meteor streaking across the sky in the Chelyabinsk

What damage can impact events cause?

Impact events are believed to have radically reshaped our planet throughout history, from the formation of the moon through to several enormous extinction events.

The Chicxulub crater is believed to have been caused by a large asteroid approximately 10km in diameter striking the Earth just over 66 million years ago, leading a very sudden mass extinction of an estimated 75% of all animal and plant life on the planet – including the dinosaurs.

A similar scale impact is not expected for the next 100 years at least, but significant damage could be caused by smaller asteroids.

Back in 2013, a meteor exploded in the atmosphere near Chelyabinsk in Russia, causing an enormous fireball, shattering windows, and leading to potentially more than a thousand people to seek medical treatment for their indirect injuries.

The SpaceX Falcon 9 rocket launches with the Double Asteroid Redirection Test, or DART, spacecraft onboard, Tuesday, Nov. 23, 2021, Pacific time (Nov. 24 Eastern time) from Space Launch Complex 4E at Vandenberg Space Force Base in California. DART is the world...s first full-scale planetary defense test, demonstrating one method of asteroid deflection technology. The mission was built and is managed by Johns Hopkins APL for NASA...s Planetary Defense Coordination Office. Photo Credit: (NASA/Bill Ingalls)
Image:NASA launches first ever asteroid deflection mission. Pic: NASA/AP

That asteroid is believed to have been roughly 20 metres in size and was completely undetected before it entered the atmosphere, in part because it approached Earth from the direction of the sun – meaning it reflected no light to telescopes on Earth revealing its approach.

When it burned up in the atmosphere and exploded it briefly outshone the sun and the heat from the blast inflicted severe burns on observers below, as well as smashing windows and rattling buildings.

According to Johns Hopkins Applied Physics Laboratory, the Chelyabinsk meteor created “an airburst and shockwave that struck six cities across the country - and [sent] a stark reminder that dangerous objects can enter Earth’s atmosphere at any time”.

“Astronomers estimate there are tens of thousands of near-Earth asteroids close to 500ft (150m) wide and larger, big enough to cause regional devastation if they actually hit Earth.

“The Chelyabinsk object was just about 60ft (18m) wide, demonstrating that even small asteroids can be of concern - and making real-world tests of space-based planetary defence systems all the more important,” the university added.

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Science & Tech

COVID-19: Facebook removes Chinese-backed network of fake accounts spreading coronavirus disinformation

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The false profiles, with links to Chinese-backed agencies, originated and spread false claims the US pressured scientists to blame China for COVID-19.

Facebook has removed hundreds of fake accounts linked to a campaign by China to spread unfounded claims about the pandemic.

The bogus profiles originated claims the US pressured scientists to blame China for COVID-19.

An investigation found these claims were amplified by employees of Chinese state-run companies, soon becoming the subject of domestic news headlines.

“In effect it worked like an online hall of mirrors, endlessly reflecting the original fake persona and its anti-US disinformation,” Ben Nimmo, who leads investigations into disinformation at Meta, the parent company of Facebook and Instagram, said.

The social media company said one of the accounts belonged to a fictitious Swiss biologist named Wilson Edwards.Advertisement

The Wuhan Institute of Virology that it is claimed COVID-19 may have escaped from
Image:The Wuhan Institute of Virology that it is claimed COVID-19 may have escaped from

In July, when the operation began, Mr Wilson’s profile claimed US officials were using “enormous pressure and even intimidation” to get scientists to back calls for renewed investigations into the origin of coronavirus.

Within hours, hundreds of other accounts – some only created only that day – began liking, reposting or linking to the post.

Many of the accounts were later found to be fake, with some of the users posing as westerners and others using likely fabricated profile photos.

Facebook said it found links between the accounts and a tech firm based in Chengdu, China, as well as to overseas employees of Chinese infrastructure companies.

Within a week of the initial post, large media outlets in China were reporting on the claims as if they had been made by a real scientist.

The operation was exposed when Swiss authorities announced in August that they had no record of any biologist with that name.

In all, Meta removed about 600 accounts on Facebook and Instagram that were linked to the network.

China’s Ministry of Foreign Affairs has said in the past that the country’s government does not employ trickery on social media.

Coronavirus emerged in Wuhan, China in December 2019 before spreading around the world.

Different governments, experts and organisations, including the US, have suggested the virus may have come from a lab leak in the city – a claim China vehemently denies.

That theory was dismissed by a team led by the World Health Organisation (WHO) that spent four weeks in and around Wuhan in January and February.

However, their report, released in March, was criticised for not finding sufficient evidence to discard the idea – and the WHO’s director-general has since said there had been a “premature push” to rule out the lab leak theory.

The US carried out their own investigation and came to the same conclusion.

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Science & Tech

Meta: UK competition regulator tells Facebook owner to sell GIF library Giphy

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The investigation into the acquisition has been acrimonious, with Meta previously being fined £50m by the CMA for deliberately refusing to comply with the regulator’s inquiries.

Facebook’s owner Meta has been issued a legally binding order to sell the GIF library Giphy after an investigation found the takeover “could harm social media users and UK advertisers”.

The Competition and Markets Authority (CMA) launched an in-depth investigation into the deal in April after raising a number of concerns. It subsequently warned of the potential forced sale in August.

Giphy – a website for making and sharing animated images, known as GIFs – was acquired by Facebook (now Meta) in May last year to integrate the GIFs with Instagram, but the CMA has now ordered the acquisition to be unravelled.

Sky News understands Facebook intends to appeal the CMA’s decision. It has four weeks to do so and the appeal would go to a the Competition Appeal Tribunal, which is independent of the CMA.

Meta could potentially challenge that ruling in the UK courts, but only on points of law.Advertisement

Facebook has rebranded to Meta
Image:Facebook’s parent company was renamed Meta last month

Stuart McIntosh, who chaired the independent inquiry into the acquisition, said: “The tie-up between Facebook and Giphy has already removed a potential challenger in the display advertising market.

“Without action, it will also allow Facebook to increase its significant market power in social media even further, through controlling competitors’ access to Giphy GIFs.

“By requiring Facebook to sell Giphy, we are protecting millions of social media users and promoting competition and innovation in digital advertising,” Mr McIntosh explained.

The investigation into the acquisition has seen points of acrimony, with Meta being fined a record £50m by the CMA for deliberately refusing to comply with the regulator’s inquiries.

Meta argued that it has been in compliance with the competition watchdog’s primary orders at all times.

At the time of the fine, the company complained that the CMA delayed for seven months a request to amend these orders which was eventually agreed in what the company described as nearly an identical manner to what had been requested.

When Facebook first merged with Giphy it terminated the image library’s advertising services, “removing an important source of potential competition” according to the CMA.

This was considered “particularly concerning given that Facebook controls nearly half of the £7 billion display advertising market in the UK”.

However in Meta’s response to the preliminary findings, the social media giant described the acquisition as a simple vertical merger and said that Giphy was financially troubled and suggested that its attempts to monetise its GIF library for display advertising were unsuccessful.

“If GIF paid alignments were the promising business model that the CMA believes they are, then one would expect to encounter them in the real-world at scale… Yet that is not the case,” the response stated.

According to the regulator, the acquisition potentially also enabled the social media giant to change the terms of access to the GIF library for its competitors.

“For example, Facebook could require Giphy customers, such as TikTok, Twitter and Snapchat, to provide more user data in order to access Giphy GIFs.

“Such actions could increase Facebook’s market power, which is already significant,” the regulator said.

In its review of the merger, the CMA said it risked entrenching Meta’s market dominance, noting that its platforms (Facebook, Instagram, and WhatsApp) already accounted for 73% of all user time spent on social media in the UK.

A spokesperson for Meta said: “We disagree with this decision. We are reviewing the decision and considering all options, including appeal. Both consumers and Giphy are better off with the support of our infrastructure, talent, and resources.

“Together, Meta and Giphy would enhance Giphy’s product for the millions of people, businesses, developers and API partners in the UK and around the world who use Giphy every day, providing more choices for everyone.”

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Health

COVID-19: Mild and moderate cases during pregnancy doesn’t harm babies’ brains, finds study

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Parents should be reassured, there is “no evidence that a maternal SARS-CoV-2 infection has any effect on the brain development of the unborn child” say scientists.

Mild and moderate coronavirus infections in pregnant women appear to have no effect on the brain of the developing foetus according to a new study.

Two years into the COVID-19 pandemic “there is evidence that pregnant women are more vulnerable” to the coronavirus, according to a study presented to the Radiological Society of North America (RSNA).

The new study aims to identify what the possible consequences are for the unborn child if the mother is infected during pregnancy, and to study the likelihood of the virus being passed on to the foetus.

“Women infected with SARS-CoV-2 during pregnancy are concerned that the virus may affect the development of their unborn child, as is the case with some other viral infections,” said Dr Sophia Stoecklein, senior author of the study.Advertisement

“So far, although there are a few reports of vertical transmission to the foetus, the exact risk and impact remain largely unclear,” added Dr Stoecklein, from the department of radiology at Ludwig Maximilian University of Munich.

“The aim of our study was to fill this gap in knowledge regarding the impact of a maternal SARS-CoV-2 infection on foetal brain development,” she added.

MRI scans were used to study 33 pregnant women who were infected with COVID-19 during their pregnancy, with the women roughly 28 weeks into the pregnancies at the time of the scan.

The scans were evaluated by radiologists with years of experience in foetal MRIs who found that the brain development in the assessed areas was age-appropriate in all of the children, with no findings indicating any infection affected the brains.

“In our study, there was no evidence that a maternal SARS-CoV-2 infection has any effect on the brain development of the unborn child,” Dr Stoecklein said. “This fact should help to reassure affected parents.”

But she cautioned that only mothers with mild to moderate symptoms who were not hospitalised were included in the study, meaning the impact of “severe infection on brain development in the foetus has not been conclusively determined”.

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