In April, experts from NASA and other space agencies around the world faced a worrisome hypothetical scenario-a mysterious asteroid 35 million miles from the Earth had just been discovered.
Space rocks should strike us in six months. This situation was invented as part of a week-long exercise to simulate an upcoming asteroid to help American and international experts practice how to deal with this situation. Business insider.
The simulation provides an embarrassing lesson-if an asteroid is found so late, no one can do anything to prevent it from hitting the earth. Experts believe that given the six-month deadline for this scenario, there is no existing technology that can stop the asteroid. In such a short period of time, there is no spacecraft capable of destroying or pushing asteroids away.
Paul Chodas, director of NASA’s Near-Earth Object Research Center, helped organize a recent simulation and five previous similar simulations. He said that this exercise prepared participants for failure: “We call this the last-minute warning scenario. Its design is very challenging.”
In fact, if a fictitious asteroid like this sails to Earth, scientists will need years of warning instead of months of warning. According to Jordas, the minimum period is five years. MIT astronomer Richard Binzel and others say it will take at least ten years.
Binzel told “Business Insider”: “In the face of real asteroid threats, time is the most valuable commodity.”
But scientists have not yet discovered that most dangerous space objects pass near the earth, which means that we have a small chance of responding in five to ten years. In 2005, the US Congress tried to solve this problem by requiring NASA to find and monitor 90% of all objects above 140 meters close to the earth. An asteroid of this size may wipe out a city the size of New York City. But so far, NASA has discovered only 40% of these spacecraft.
Binzel said: “This means that we now rely on luck to protect ourselves from larger asteroids. But luck is not the plan.”
In the NASA simulation, the scientists involved did not know the size of the asteroid until the asteroid should hit the earth one week.
Sara Sannett of the Planetary Science Institute who participated in the study said: “We don’t know whether the width of the object is 35 meters or 500 meters. The difference is huge.” For example, a 35-meter asteroid may be in the atmosphere. It explodes and sends shock waves to its surroundings, and a 500-meter asteroid may destroy a city and cause consequences in a French-scale area.
Therefore, it is important to understand the problems we face when preventing asteroids from hitting the earth. These factors include size, the path it travels around the sun, and the composition of the asteroid. Using this data, scientists can evaluate strategies to break or disrupt the asteroid’s trajectory.
“It takes time to understand your enemy,” Binzel said.
Sonnett believes that ideally, scientists can study a dangerous asteroid because it passed the Earth many times in an orbit around the sun before its trajectory caused a collision. Observing a passing asteroid may take years or even decades.
NASA has three main tools in its planetary defense system. The first is to detonate an explosive device near the asteroid and smash it into less dangerous pieces. The second is to guide the laser, which can heat and vaporize asteroids to change their trajectories. The third is to send a spacecraft to hit an asteroid and get it out of orbit. NASA will test the latest strategy. Therefore, it will send a probe to the asteroid Dimorphos in the fall of 2022 and deliberately hit it.
Jordas said: “Any strategy takes years.”
After that, it will take one to two years until the asteroid’s orbit around the sun changes enough to take it farther from the earth. This is why deadlines are important. The sooner scientists find dangerous objects in space, the easier it is to transfer missions. Of course, if no one knows that the asteroid is coming, all methods are useless.
Binzel said: “I think it’s best to invest in knowledge. The best investment is to find what is waiting for us in space.”