Asteroid 'crushing' system to protect Earth

The American scientist proposed the idea of ​​​​launching a spacecraft to crash into the asteroid and make it explode into many pieces so that it is no longer capable of causing danger.

Professor Philip Lubin at the University of California Santa Barbara developed an idea to protect the Earth called PI-Terminal Defense for Humanity. PI stands for Pulverize It, which means crushed. Lubin believes that crushing a celestial body that is rushing towards Earth is an effective solution to protect humanity when there is only a short time to manage. He presented his idea at the 2021 Planetary Defense Conference, and also received funding under the NASA Innovative Advanced Ideas (NIAC) program.

Simulation of asteroids flying close to Earth.

Many solutions to protect the Earth from asteroid impacts have a very long implementation time. If experts know the risk of impact months or years in advance, experts can launch impactors on the asteroid to deflect it. With a sufficiently long preparation time, even a small impact can redirect a large asteroid.

Lubin's solution is geared toward unexpected situations, when scientists detect a potential collision too late. Essentially, he wanted to break the celestial body into small pieces so that they would burn up in the Earth's atmosphere.

Specifically, Lubin wanted to build a spacecraft that could not only impact the asteroid with momentum, but could also explode. The craft will be equipped with piercing rods to hit the asteroid, some of which are filled with explosives. The explosion will destroy it into many small pieces, hopefully 15 meters or less in diameter.

The pieces will form a debris cloud. Depending on the size of the asteroid, the size of the spacecraft, and the distance it was from Earth when it exploded, some debris could hit Earth. However, most of them will be destroyed by friction with the atmosphere.

Plan to destroy asteroids by PI system.

"The effectiveness of the new method depends on the interception time and asteroid size. However, it still provides effective protection for Earth against asteroids hundreds of meters in diameter and close to being eliminated. remove the threat of mass destruction they pose," explains Lubin.

According to Lubin, the PI system could be placed in Earth's orbit or even on the Moon. "Compared to other risk reduction approaches, this approach represents a cost-effective, verifiable and deployable approach with a streamlined development and testing path. Pre-installation of the system systems in Earth or Moon orbit allow for a quick response in less than a day if needed," Lubin said.

The moon has several advantages. For example, this object has no atmosphere, so if used as a base to observe near-Earth asteroids, experts can detect them from afar with advanced tools. The moon also has a smaller escape velocity than Earth, making launches easier and less expensive.

Launching a large spacecraft carrying explosives from Earth is also gradually becoming more possible. Heavy-duty launch vehicles like SpaceX's Falcon Heavy, NASA's Space Launch System (SLS) and others are ushering in a new era of powerful rocket technology.

The PI system only needed five hours before impact to destroy an asteroid the size of the Tunguska event, says Lubin. The object is believed to be about 50 meters in diameter and exploded with the force of 10 million tons of TNT. It flattened millions of trees in a remote area of ​​Siberia.

If an object of similar size were to explode in the sky above the city, the consequences would be dire. The Chelyabinsk meteorite that crashed through the Russian sky in 2013 broke a series of windows and injured about 1,500 people while being only 20 meters in diameter.

The PI system is also effective against large asteroids such as Apophis, which are up to 370 meters in diameter. According to Lubin, the PI system can successfully destroy objects the size of Apophis if intercepted 10 days before it hits Earth.