Thread: China builds 'planetary defence' team as concerns grow over 2024 YR4 asteroid

A Chinese defence agency is recruiting space researchers following the discovery of a large asteroid with a 2.2 per cent chance of striking Earth in 2032.

China has started assembling a planetary defence team to counter the threat of near-Earth asteroids following the discovery of a large asteroid that could strike our planet in seven years.


Last Friday (Feb 7), the European Space Agency (ESA) updated their probability of asteroid 2024 YR4 hitting Earth in 2032 to 2.2 per cent, putting it at the top of the agency’s risk list.

The asteroid, estimated to be 40m to 90m wide, was discovered by the University of Hawaii's Institute of Astronomy in late December. The discovery activated global asteroid response mechanisms after its odds of an impact with Earth surpassed an international monitoring threshold.


Weeks after the asteroid's discovery, a special projects centre at China's State Administration of Science, Technology and Industry for National Defence posted a recruitment notice listing three available roles for a "planetary defence post".


The centre, which is responsible for aerospace engineering research and implementation and Earth observation, is recruiting graduates to study asteroid monitoring and create early warning methods, according to the notice posted last month on the WeChat account of the journal China Space Science and Technology.


There are various methods that could be used to try to stop an asteroid from hitting Earth. In the world's first successful planetary defence test in 2022, United States space agency NASA altered an asteroid's trajectory by colliding with it.


Li Mingtao, a researcher at the Chinese Academy of Science's National Space Science Centre, told China Science Daily on Monday that China had made "great progress" in asteroid defence.


"In the future, we must not only comprehensively strengthen equipment configuration and performance … but also cultivate a team of talent dedicated to asteroid defence and contribute Chinese wisdom and Chinese strength to protecting the safety of the Earth," Li said.


According to his online profile, Li works on designing innovative asteroid defence plans. The site said he aimed to propose a Chinese plan for near-Earth asteroid early warning and defence.

In September, China unveiled a conceptual plan for its first mission to defend against a near-Earth asteroid. The mission aims to observe an asteroid and then hit it with a spacecraft to alter its path in around 2030, according to state media.

China is also part of the International Asteroid Warning Network (IAWN) and the Space Mission Planning Advisory Group (SMPAG), two international bodies that coordinate the sharing of information and response to asteroids and other near-Earth objects.


The 2024 YR4 asteroid is big enough to cause localised damage in the event of an impact with Earth.


Li said that while the asteroid was likely to either fall into the ocean or disintegrate as it entered the Earth's atmosphere, if it did hit land the shock waves and radiation generated could destroy a medium-sized city.


In 2013, an asteroid measuring 20m wide hit Chelyabinsk, Russia, with an explosion equivalent to 30 atomic bombs. It damaged 300 houses and injured 1,500 people.

Li said that if the 2024 YR4 asteroid hit an urban area, it could injure tens of thousands of people.


At the end of January, NASA and the ESA both released independent estimates saying the probability of an impact with Earth was above 1 per cent. Those odds, along with the size of the asteroid, put it above the threshold for IAWN and SMPAG to initiate a response.


In their estimate released late last month, the ESA put the likelihood of impact at 1.2 per cent. The probability could continue to change – and even fall to zero – as scientists observe and obtain more data on the asteroid.


Li said that although public attention was focused on the asteroid, "scientists actually do not regard it as a particularly serious matter and are relatively calm".


The asteroid, which passed close to Earth in December as it made its four-year trip around the sun, will fade out of view over the next few months, so astronomers will use increasingly powerful telescopes to obtain as much data on it as possible while it is still visible.


"By the end of the observation in April, we will have more data, and when the new observation window arrives in 2028, we will be able to judge the probability of it hitting the Earth more clearly," Li said.


"At that time, the United Nations will organise another discussion to decide whether to design a defence plan."


This article was first published on SCMP.

China builds 'planetary defence' team as concerns grow over 2024 YR4 asteroid - CNA

Yay Chiang Mai.

Oh, shit.

What you need to know about 2024 YR4, the asteroid that could hit Earth in about eight years' time


The asteroid currently has about a 2 per cent chance of colliding with Earth in December 2032, according to NASA and the European Space Agency.

A recently detected asteroid about the size of a football field currently has a greater than 2 per cent chance of colliding with Earth in about eight years' time.


Scientists are not panicking yet, but they are watching the asteroid, dubbed 2024 YR4, closely.

Here is what you need to know about it:


What do we know so far?


The asteroid was first spotted on Dec 27, 2024, through a telescope at the El Sauce Observatory in Chile. The telescope is part of the Asteroid Terrestrial-impact Last Alert System (ATLAS), which comprises several telescopes around the world.


ATLAS, which is funded by the United States' space agency NASA, is managed by the University of Hawaii's Institute for Astronomy.


Based on its brightness, astronomers estimate that 2024 YR4 is between 40m and 90m wide.


By New Year's Eve, the asteroid had been reported as an object of concern to Kelly Fast, acting planetary defence officer at NASA.


"You get observations, they drop off again. This one looked like it had the potential to stick around," she told AFP.

The risk assessment kept climbing, and on Jan 29, the International Asteroid Warning Network (IAWN), a global planetary defence collaboration, issued a memo on the asteroid.


2024 YR4 follows a highly elliptical four-year orbit, swinging through the inner planets before shooting past Mars and out towards Jupiter.


For now, it's zooming away from Earth – its next close pass will not come until 2028.

How has the probability of it hitting Earth changed since its discovery?


In its Jan 29 memo, IAWN said that the asteroid had a 1.3 per cent chance of impacting Earth on Dec 22, 2032, according to NASA and European Space Agency (ESA) data.

As of Feb 5, the space agencies had upped this to 1.6 per cent. On Feb 7, ESA raised the figure again, to 2.2 per cent.


As of Wednesday, ESA's figure was 2 per cent and NASA's 2.1 per cent.


The odds of an impact will continue to change and could also drop to zero.


"The odds are very good that not only will this not hit Earth, but at some point in the next months to few years, that probability will go to zero," Bruce Betts, chief scientist of The Planetary Society, told AFP.


Such a scenario unfolded in 2004 with Apophis, an asteroid initially projected to have a 2.7 per cent chance of striking Earth in 2029. Further observations ruled out an impact.

How much damage could it cause?


The most infamous asteroid impact occurred 66 million years ago, when a space rock with a width of about 10km triggered a global winter, wiping out the dinosaurs and 75 per cent of all species.


By contrast, 2024 YR4 falls into the "city killer" category – if it hits Earth, the impact will have the potential to wreak city-level devastation, depending on where it strikes.


"If you put it over Paris or London or New York, you basically wipe out the whole city and some of the environs," said Betts.


According to the IAWN memo, possible impact sites include over the eastern Pacific Ocean, northern South America, the Atlantic Ocean, Africa, the Arabian Sea and South Asia.


The best modern analogue of an impact event involving 2024 YR4 is the 1908 Tunguska event, when an asteroid or comet fragment measuring 30m to 50m in diameter exploded over Siberia, flattening 80 million trees across 2,000 sq km.


Like that impactor, 2024 YR4 would be expected to blow up in the sky, rather than leave a crater on the ground.


"We can calculate the energy ... using the mass and the speed," said Andrew Rivkin, a planetary astronomer at Johns Hopkins Applied Physics Laboratory.


For 2024 YR4, the explosion from an airburst would have the energy of about 8 megatons of TNT. In other words, the blast would have more than 500 times the power of the Hiroshima bomb.


If it explodes over the ocean, the impact would be less concerning, unless it happens near a coastline and triggers a tsunami.

Should we be worried about 2024 YR4 and is there anything the world can do about it?


The world has plenty of time to prepare for 2024 YR4, experts have stressed. And if needs be, there is one tried-and-tested means of altering an asteroid's trajectory.


Rivkin led the investigation for NASA's 2022 Double Asteroid Redirection Test, or DART, mission, which successfully nudged an asteroid off its course with a "kinetic impactor" strategy that involved a collision with a spacecraft.


The target asteroid posed no threat to Earth, making it an ideal test subject.


"I don't see why it wouldn't work" again, he said. The bigger question is whether major nations would fund such a mission if their own territory was not under threat.


Other more experimental ideas exist.


Lasers could vaporise part of the asteroid to create a thrust effect, pushing it off course. A "gravity tractor", a large spacecraft that slowly tugs the asteroid away using its own gravitational pull, has also been theorised.


China, meanwhile, has begun putting together a planetary defence team.


Shortly after the discovery of the asteroid, a special projects centre of China's State Administration of Science, Technology and Industry for National Defence posted a recruitment notice listing three available positions for a "planetary defence post", the South China Morning Post reported on Monday.


The new hires will study asteroid monitoring and create early warning methods, SCMP reported, citing the notice posted last month on the WeChat account of the journal China Space Science and Technology.


China also has an existing conceptual plan for a mission to defend against a near-Earth asteroid, SCMP added. Unveiled in September 2024, the mission – which would be the first of its kind for China – aims to observe an asteroid and then hit it with a spacecraft to change its course in about 2030, according to Chinese state media.


If all else fails, the long warning time means that authorities could evacuate the impact zone.


"Nobody should be scared about this," said NASA's Fast. "We can find these things, make these predictions and have the ability to plan."

What you need to know about 2024 YR4, the asteroid that could hit Earth in about eight years' time - CNA

Originally Posted by misskit

The most infamous asteroid impact occurred 66 million years ago, when a space rock with a width of about 10km triggered a global winter, wiping out the dinosaurs and 75 per cent of all species.

Causing the K-T Boundary all around the world.

• It's the site of a mass extinction that killed off non-avian dinosaurs and 50–60% of the Earth's plant and animal life.

• The K-T boundary is marked by a high concentration of iridium, similar to that found in meteorites.

• The impact of an asteroid is thought to have caused a cloud of dust that blocked sunlight for years, killing plants and eventually dinosaurs.

Probably the most interesting piece of geology out there.

Do you happen to have some of it kept with your rock collection, Mendo?

^ Yeah, I've got loads of it.

I can sell you some if you like?

Sure thing, put me in for a 100 baht shaving.

A cynic would say that a Chinese planetary defence team would be happy just nudging it off course....onto New York or Washington perhaps.

For any nervous Nellies who might actually worry about this asteroid hitting in our lifetime, the ESA update the odds on their website: Asteroid 2024 YR4 – latest updates – Rocket Science

Currently at 2%, which is less than the chance of throwing "snake eyes" in craps...but that does happen eventually!

The chinkies saving the day is rather similar to the plot of "The Wandering Earth".

Do look up: How Earth can defend itself against asteroid

There is a very small chance that an asteroid capable of taking out an entire city could strike Earth in less than eight years. But even if this asteroid is hurtling our way, humanity is now able to defend itself against such a threat, experts say.


The odds that the recently discovered asteroid will hit Earth on December 22, 2032 have now risen to 3.1 percent, NASA said on Tuesday, the highest probability for an impact by such a large space rock in modern forecasting.


"Don't panic," Richard Moissl, head of the European Space Agency's planetary defence office, told AFP.

As astronomers gather more data, the odds of a direct hit are widely expected to edge upwards before rapidly dropping down to zero.


However, even in the unlikely event that the probability does keep rising up to 100 percent, "we are not defenceless", Moissl emphasised.


Here are some of the ways that humanity could deflect or destroy the asteroid known as 2024 YR4.


- Smash a spacecraft into it -


Only one planetary defence strategy has been tried out on an actual asteroid.


In 2022, NASA's Double Asteroid Redirection Test (DART) deliberately smashed a spacecraft into the 160-metre-wide Dimorphos asteroid, successfully altering its orbit around a larger space rock.

An advantage of this plan is that we could hit the 2024 YR4 asteroid with multiple spacecrafts, observing how each one changed its trajectory, Bruce Betts, chief scientist for the nonprofit Planetary Society, told AFP.


The asteroid discovered in December is estimated to be 40-90 metres wide -- roughly half the size of Dimorphos.


"You have to take care not to overdo it," Moissl warned.


If the spacecraft partially destroyed the asteroid, it could send "bits flying off" that still head towards Earth, he said.


If this kind of mishap changed the eventual impact site on Earth -- for example, "from Paris to Moscow" -- that would likely cause major problems back home, Betts added.

- Tractor, ion beams, paint -


A separate idea called a gravity tractor involves a large spacecraft flying up near the asteroid and -- without touching it -- using its gravitational pull to tug it away from Earth.


Another non-contact plan would put a spacecraft near the asteroid armed with thrusters that would exert a "constant stream of ions" to shove the asteroid off course, Moissl said.


Scientists have also considered spray painting one side of the asteroid white, increasing its reflectiveness so it slowly changes trajectory.


These subtler strategies would require reaching the asteroid sooner than for some more severe options.

- The nuclear option -


Or we could also just blow it up with a nuclear bomb.


Rather than drilling a nuclear weapon deep into an asteroid -- as depicted in the 1998 sci-fi action movie "Armageddon" -- this would likely involving detonating a bomb nearby.


Last year, US researchers testing out this theory on a marble-sized mock asteroid in the lab found that the x-rays from a nuclear blast would vaporise its surface and send it shooting off in the opposite direction.


Even setting aside the ethical, political and legal issues of sending nukes into space, this is considered more of a last-ditch plan for kilometres-wide asteroids like the one that killed off the dinosaurs.


And again, there is a risk that a nuclear explosion could still send unpredictable chunks hurtling towards Earth.


- Lasers -


Along less dangerous but similar lines, another idea is to shoot laser beams from a spacecraft to vaporise the side of an asteroid, pushing it away.


Lab experiments suggest this plan is viable, but it is not one of the "top techniques" being looked at, Betts said.


- If all else fails -


If necessary, deflecting this asteroid is "doable, but it depends on the speed at which we move as a planet", Moissl said.


While experts and space agencies will make their recommendations, ultimately the decision on how to tackle the asteroid will be made by world leaders.


If all else fails, we will have a good idea of the strike zone of the asteroid -- which is not a "planet killer" and at most could threaten a city, Moissl said.


This means that preparing for impact, potentially including evacuation if the area is populated, will be the last line of defence.


"Seven and a half years is a long time to prepare," Moissl said, re-emphasising that there is a roughly 97 percent chance the asteroid will miss Earth.

Do look up: How Earth can defend itself against asteroid

It's those damn bugs again!



Chinese Planetary Defence Team:

^ That last article posted says the odds have risen.

The odds that the recently discovered asteroid will hit Earth on December 22, 2032 have now risen to 3.1 percent, NASA said on Tuesday, the highest probability for an impact by such a large space rock in modern forecasting.

Originally Posted by misskit

That last article posted says the odds have risen.

Yes. But that is due to how data come in and are evaluated. It is still expected that the likelyhood will probably drop to 0 well ahead of the close encounter time.

Note to self schedule sort out back paddock and garage after 2033, may not need to do it at all.