In the face of near-Earth objects that may pounce on the earth at any time due to a slight change, and cause major harm, should humans passively defend or actively respond? Astronomers at the University of California, Santa Barbara (UCSB) believe that we should be on the initiative. The team recently proposed a new method to directly crush celestial bodies by placing fuel rods that can penetrate them in their orbits. Opportunity for the earth.
In February 2013, astronomical observations around the world turned to an asteroid named 2012 DA14, which was closer to the earth than the high ground orbit where we placed traditional communication satellites, with a diameter of 50 meters, although it has been predicted Its orbit will pass by the earth, but an inattention can still cause casualties in densely populated areas of the earth.
What we did not notice, however, is that at the same time, another asteroid with a diameter of about 19 meters has slipped into the earth and exploded over the Russian city of Chelyabinsk, shattering windows, damaging buildings, and causing Nearly 2,000 people were injured, but fortunately no one was injured or killed.
For planetary defense scientists, the asteroid impact that occurred under their noses made them pay more attention to the importance of detecting, tracking, and countering dangerous celestial bodies and other planetary defenses.
Although events like threats to the city of Chelyabinsk are rare, occurring only once every 50 to 100 years, they are potentially large-scale destructive. For example, an air-blast in the eastern Siberian sky in 1908 would cost thousands of square kilometers. An area of forest was razed to the ground, or the Chicxulub meteorite that wiped out the cause of the dinosaurs 66 million years ago.
There will be larger near-Earth objects approaching in the future
In addition, we must not ignore the threats of other celestial bodies that will pass the earth at close range in the future, such as the asteroid 99942 with a diameter of 370 meters and will meet with the Earth on April 14, 2029, or the asteroid with a diameter of 490 meters and will rub shoulders in 2036. The asteroid 101955 passed by.
Although it is currently calculated that these celestial bodies do not have a risk of impacting the Earth, any change in their orbits may cause them to move closer to the Earth. I don’t know which time they hit humans, there will be no chance to come back.
In response, the team of Philip Lubin, professor of physics at the University of California, Santa Barbara, proposed a PI plan to deal with alien celestial bodies more proactively. Rods of 10 to 30 cm and 2 to 3 meters long can be crushed when asteroids or comets hit them very quickly.
▲ Schematic diagram of near-Earth object slicing technology. (Source: University of California, Santa Barbara)
The researchers said that instead of finding a way to deflect the near-Earth object, it is better to change the direction and directly break the asteroid into smaller pieces that are not threatening to the Earth in space. Compared with the deflection method, the former needs to be impacted several months in advance. For example, NASA is expected to launch the DART asteroid self-collision mission in November this year, in preparation for impacting the celestial body Dimorphos in September next year to test asteroid deflection technology.
On the contrary, “slicing technology” can intercept asteroids or comets when they are closer to the earth. Small targets like the Chelyabinsk event only need to be processed in a manner similar to intercontinental ballistic missiles a few minutes before the impact. Objects like asteroid 99942 can also be intercepted 10 days before impact and can be deployed using SpaceX’s Falcon 9 or NASA’s SLS rocket.
Scientists say, it’s like we are vaccinated to prevent related diseases in the future. If human beings already have the technology to control their own destiny, why not try to fight it head-on?
(First image source: NASA)
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