A study from Johns Hopkins University aims to dispel the previous theory that bigger asteroids are more susceptible to explosions. This meant that in case a killer asteroid is headed to Earth, blowing it up would be the best option.
The research, which was published in Icarus, observed that a 25-kilometer diameter (15.5 miles) target asteroid is hit by a half-mile diameter asteroid at approximately 3 miles per second. Unlike in previous simulations and models where the bigger asteroid was completely destroyed, the newer model showed different results.
"We used to believe that the larger the object, the more easily it would break, because bigger objects are more likely to have flaws. Our findings, however, show that asteroids are stronger than we used to think and require more energy to be completely shattered," says one of the paper's authors.
Charles El Mir, who recently graduated PhD from Johns Hopkins University, also stated that scientists have been using small rocks at a laboratory scale (fist size) in trying to understand the way an asteroid would behave upon impact. However, previous research teams found it difficult to translate these data into city-size asteroids.
Bigger Asteroids Have More 'Flaws'
The previous assumption was that if an asteroid is bigger, perhaps it has more cracks and pores, meaning it can be easily destroyed. However, the research team used a newer computer model called Tonge-Ramesh, which accounts for a more detailed representation of a collision between a bigger and smaller asteroid.
The first phase of the collision shows the bigger asteroid suffering millions of cracks. The impact rippled throughout the asteroid's surface resulting in a large crater. Meanwhile, the second phase showed the asteroid's remaining core loosely holding together the scattered fragments. As seen in the model, the asteroid was not completely destroyed, and it retained significant strength.
The researchers concluded that more firepower and energy are needed to destroy such an asteroid completely.
If You Can't Destroy Them, Mine Them
This leads to the second part of the research, where K.T. Ramesh, director of the Hopkins Extreme Materials Institute, attempted to shed some light. He believes that destroying a killer asteroid is not the most practical way to save humanity. NASA will have more success in developing a spacecraft that will act as a battering ram to push the asteroid off its course. What Ramesh intends to do with the research is to anticipate what to expect if mankind decided to explore more asteroids.
In case humanity makes that leap, mining asteroids is a possibility because they are rich in resources including water, minerals, and metals. If possible, asteroids could even provide the raw materials needed to refuel spaceships without the need to return to Earth. Ongoing research has even suggested building a space station within an asteroid.