Some of China's top universities are working on a new method of not only detecting and tracking asteroids, but calculating whether they pose a potential danger to the Earth, China's Science and Technology Ministry's official newspaper the Science and Technology Daily first reported.
Building the strongest radar ever
This new method, an initiative spearheaded by Beijing Institute of Technology, is called China's Compound Eye, or China Fuyan, and is set up in Chongqing in the South, and will feature what the Chinese media is describing as the radar with the farthest range out of any other on Earth - a total of 150 million kilometers away.
For context, the Moon on average orbits the Earth at a distance of around just 340,000 kilometers, so this is significantly farther. In fact, it's close to the approximate distance of the Earth to the Sun.
This will be accomplished by setting up a radar array of around 20 large 25-30 meter antennae that will be able to send signals into space within the radar's range.
These antennae will essentially act in a manner similar to the compound eyes of insects, which is where it gets its name from, Beijing Institute of Technology president and Chinese Academy of Engineering member Long Teng told China's Global Times news outlet.
By doing this, they will be able to bounce the signals off of asteroids, helping them track and image them and even testing to see if they could possibly impact the Earth.
This will also be helped by four 16-meter-wide radar dishes to test the system and work to achieve a 3D rendering of the Moon. At the time of writing, two of the four radars have been built and are set to become operational in September, the Global Times reported.
That is the first stage of the project's rollout. The second stage is fully increasing the number of antennae to better increase the scope. The third stage will be to launch the first-ever deep-space radar and try out 3D imaging of asteroids and other objects in space, according to the Global Times.
"Since the large radar telescope at Arecibo, Puerto Rico, tragically broke down, humanity’s radar capabilities for asteroids observations are low. I’m eager to see the Chinese radar telescope in action and hope their project will succeed."
Dr. David Polishook, Israels Weizmann Institute of Science
Asteroids: Thousands of possible apocalypses in space
An asteroid impact is arguably the worst possible natural disaster that could occur on Earth, due to the fact that we currently have no way to stop it and that the sheer level of destruction that can be caused by large enough asteroids can range from damaging to catastrophic to the end of the world as we know it.
According to research from the Davidson Institute of Science, the educational arm of Israel's Weizmann Institute of Science, an asteroid over 140 meters in diameter would release an amount of energy at least a thousand times greater than that released by the first atomic bomb if it impacted Earth.
Something even larger — over 300 meters wide like the asteroid Apophis or Bennu — could destroy an entire continent. An asteroid over a kilometer in width — like the asteroid 7335 (1989 JA) — could trigger a worldwide cataclysm.
The scenario of a disastrous asteroid impact has been the subject of much popular fiction, ranging from the popular films Armageddon, Deep Impact and, most recently, Don't Look Up.
The last major asteroid impact from a significantly large enough asteroid is believed to have been in 1908 when an asteroid believed to have been around 190 meters wide or less exploded in a remote area above the Podkamennaya Tunguska River in Siberia, Russia, in what has now become known as the Tunguska event.
When the asteroid exploded in the air several kilometers above the area, it produced a massive 12 megaton explosion, causing widespread destruction for thousands of kilometers. That would make it about 800 times more powerful than "Little Boy," the approximately 15-kiloton atomic bomb detonated during World War II over Hiroshima, and 600 times more than "Fat Man," the 20-kiloton one detonated over Nagasaki three days later.
As such, it makes sense that there is vested interest in protecting the Earth from asteroids – especially one that doesn't involve the use of nuclear weapons.
Currently, the most promising method is kinetic deflection, meaning hitting the asteroid with something to slightly nudge its orbital path.
At the time of writing, the only project to have truly gotten off the ground thus far is the Double Asteroid Redirection Test (DART) Mission, an initiative developed by NASA and John Hopkins University.
The DART Mission seeks to launch a specially designed rocket to alter the path of an asteroid, effectively punching an asteroid with a rocket with enough speed to change its direction by a fraction of a percent. NASA has likened this to a "pillow fight in microgravity."
The mission was launched last November and is slated to crash into its target, the asteroid Dimorphous, in the fall of 2022.
China and asteroids
This isn't the first time China, an already growing space power, has made news regarding plans for asteroids.
Back in 2021, researchers at China's National Space Science Center in 2021 claimed that using 23 Long March 5 rockets, some of China's largest rockets, could possibly be effective at changing an asteroid's trajectory by a distance 1.4 times the Earth's radius.
Later, in April 2022, Chinese Defense Minister Wu Yanhua was cited by state media saying that the Chinese National Space Administration (CNSA) was working on a way to both detect incoming asteroids to sound the alarm if necessary and find ways of stopping impacts from occurring.
"Ground-based radar observations of NEOs provide invaluable information for long-term tracking. Because NEO impact energy scales with density, diameter, and velocity, and radar can constrain all of these, planetary radar observations are an important post-discovery characterization technique."
National Academies of Sciences, Engineering, and Medicine survey
Scientific and strategic implications
As a means of asteroid detection, there is plenty of scientific precedences supporting the viability of the Compound Eye.
According to an April survey by the National Academies of Sciences, Engineering, and Medicine, radar telescopes may actually be one of the best possible tools to help protect the Earth from asteroids as they could help detect and study asteroids and calculate the probability of a possible impact, as well as how bad that impact would be.
"Ground-based radar observations of NEOs [Near-Earth Objects, such as asteroids that could possibly impact the planet] provide invaluable information for long-term tracking," the survey noted. "Because NEO impact energy scales with density, diameter, and velocity, and radar can constrain all of these, planetary radar observations are an important post-discovery characterization technique."
However, Beijing has plans for the Compound Eye that go far beyond just planetary defense.
China has become a growing space power, having made several strides in recent years. This includes landing probes on the Moon, exploring the dark side of the Moon, sending satellites and even launching their own space station. In fact, NASA has even accused China of possibly plotting to "take over" the Moon, though Beijing has denied this and dismissed these claims.
But regardless, China's space program is extensive and continues to grow.
And they don't plan to stop there, with China also hoping to use it for its Tianwen-2 mission, a decade-long project that will see a probe collect and return a sample from the asteroid 2016 HO3, also known as Kamo'oalewa, which some scientists believe might actually be a part of the Moon that had broken off.
Tianwen-2 is reportedly set to be launched in 2025, and the Compound Eye will help scan the area and find ideal landing targets for the probe, the Global Times reported.
This is important as collecting an asteroid sample is no easy feat. In fact, NASA's recent efforts to collect a sample from the asteroid Bennu found nearly ended in disaster when the lander almost sunk beneath the surface of the asteroid, which proved to be far less solid than expected and more like a ball pit.
And not only can this radar detect asteroids, it could also be used for another possible target: Mars.
The Red Planet's distance from the Earth can vary, depending on the orbits of both planets. But at its closest, Mars is just 54.6 million kilometers away, though this doesn't happen often. Back in October 2020, Mars was just 62.07 million kilometers away, according to NASA.
Overall, Mars tends to have a "close approach" to Earth about every 26 months, which would be close enough for the radar to work. And with the possible range of China's Compound Eye and Beijing's space ambitions, it remains to be seen what the future will hold.
But regardless, there are many scientists who are excited for China's new venture.
"It is great that China is joining the effort of detecting near-Earth asteroids using a radar telescope," explained Dr. David Polishook of Israel's Weizmann Institute and a member of NASA's DART Mission. "Since the large radar telescope at Arecibo, Puerto Rico, tragically broke down, humanity’s radar capabilities for asteroids observations are low. I’m eager to see the Chinese radar telescope in action and hope their project will succeed."
Reuters contributed to this report.