Although it may sound like the plot of a movie, asteroids can be a threat to life on our planet. The probability is very low, but if one big enough hits the Earth … well, let the dinosaurs say so.
The fact is that NASA has taken a new step in this matter, has approved the construction of the Near-Earth Object Surveyor (NEO Surveyor) space telescope, dedicated to planetary defense, since its mission is to identify dangerous asteroids that are in 48 million kilometers from Earth’s orbit.
One of the objectives is to increase the speed of detection, both of asteroids and comets. They believe it could discover 90 percent of asteroids 140 meters in size or larger within a decade of launch.
When a rock of that size is found, it is best done soon, as there is more time to prepare a way to deflect or destroy the object. In the last few thousand years, no one this large has been detected heading to our surface, but thousands of years is a very short time.
One of the methods being studied to combat such a threat is the DART diversion method «Double asteroid redirection test«, To be tested later this year. The idea is to hit an asteroid directly to see if they can change its speed and trajectory. In this video from 2018 they explained:
NEO Surveyor won’t hit any asteroids, it will just send itself into orbit around Earth and use its infrared sensors to discover approaching large asteroids. By using infrared, they can be detected even in direct sunlight.