While the chances of a large asteroid hitting Earth anytime soon are considered remote, if such an event does ever occur, the consequences could be devastating. It’s therefore vital that we constantly observe the solar system for any hazardous asteroids coming our way.
At the current time, NASA tracks around 28,000 near-Earth asteroids to assess their impact risk. The space agency says that each year that figure rises by around 3,000 as more asteroids are discovered.
But in the coming years, it expects that number to increase dramatically as more powerful telescopes come online.
Ahead of the rapid uptick, scientists at the Center for Near Earth Object Studies (CNEOS), which is managed by NASA’s Jet Propulsion Laboratory, have created a next-generation impact monitoring algorithm called Sentry-II to better evaluate the impact probabilities of near-Earth asteroids.
“Popular culture often depicts asteroids as chaotic objects that zoom haphazardly around our solar system, changing course unpredictably and threatening our planet without a moment’s notice,” JPL said. “This is not the reality. Asteroids are extremely predictable celestial bodies that obey the laws of physics and follow knowable orbital paths around the sun.”
But it added that occasionally an asteroid’s path can take it very close to Earth, and due to what it describes as “small uncertainties” in the asteroid’s position, an impact with our planet is sometimes a very real possibility. The good news is that Sentry-II will provide scientists with more accurate data that will result in more reliable evaluations regarding its risk to Earth.
The video below shows the kind of challenges faced by scientists when attempting to calculate the path that an asteroid will take. It also explains how NASA’s OSIRIS-REx spacecraft has been providing additional data about one particular potentially hazardous asteroid, called Bennu.
So what happens if scientists determine that a large asteroid is on course to impact Earth in an event that could cause cataclysmic damage? Well, NASA is testing a defense system right now. Its recently launched DART mission will attempt to alter the path of an asteroid by crashing a spacecraft directly into it. If the mission is a success, the method will become our main form of defense against any dangerously large asteroids heading our way.
