NASA's new tool offers predictive capability for asteroid strikes

NASA's new asteroid impact hazard system could help predict where and when dangerous space rocks will hit Earth.

The space agency unveiled its new system on November 30, which is designed to provide a three-decade heads-up on potential asteroid strikes and estimate the impact severity.

The system, known as the asteroid impact hazard system, was developed in collaboration with the European Space Agency (ESA). It pulls from NASA's catalog of detected near-Earth objects (NEOs) – which are asteroids and comets on orbits that pass close to Earth – to find potential collisions with the planet.

The system is particularly focused on finding asteroids that are believed to pose a threat of striking Earth with a force powerful enough to alter life on the planet – known as civilization-altering strikes.

NASA's Planetary Defense Coordination Office leads the agency's efforts to find and monitor NEOs and develops technology that could be used to alter the trajectory of an asteroid or comet, if deemed necessary.

The new system is intended to provide advance warnings of potential asteroid strikes and improve the accuracy of impact predictions. It is expected to generate new insights into what to expect and how to prepare for a potential strike.

According to NASA, the system performs dozens of simulations for each potential collision, taking into account various factors such as the object's orbit and likelihood of fragmentation.

The results are then ranked based on the potential impact hazard of the NEO, helping officials determine which objects require further investigation and consideration for deflection.

NASA's previous predictions system, known as Sentry, provided between 0 and 10 years of warning for potential strikes.

The new system is expected to improve that range by 30 years, giving people more time to prepare and decide on possible deflection options.

NASA has not detected any imminent threats to Earth from asteroids, according to the new system.

However, the agency estimates that there is a 1 in 300 chance that a potential extinction-level event will occur in the next 300,000 years.

Experts believe roughly once a century, an object the size of the one that struck Tunguska, Russia, in 1908 – which was roughly 30 meters (100 feet) across and flattened 800 square kilometers (300 square miles) of forest – will hit Earth.

But collisions with larger objects could be much more devastating.

For example, the asteroid believed to have caused the mass extinction of dinosaurs is estimated to have been between 10 and 15 kilometers (6 to 9 miles) wide.

NASA's asteroid impact hazard system is just one of many efforts under the agency's planetary defense strategy, which is focused on finding, tracking, and learning how to intercept potentially hazardous NEOs.

The agency's NEO Surveillance Mission, which is targeted for launch in 2025, will more comprehensively determine the population of small asteroids in NEOs and determine how often they pass close to Earth.

This information will help improve impact predictions and determine which objects warrant further attention.

In the event that an asteroid is discovered too late for deflection, NASA is also investigating ways to mitigate the effects of impact.

This includes schemes like the "gravity tractor," which involves using the gravity of a spacecraft to nudge an asteroid into a less dangerous orbit.

The agency is also investigating technologies to interfere with an asteroid's trajectory, including through the use of a directed energy or nuclear blast.

"Knowing what we know now, NASA has made incredible progress in working toward finding, tracking, and understanding these potential threats," said NASA Chief Planetary Scientist James Green in a statement. "We are much better prepared to prevent an asteroid impact than we were 20 years ago, but we must remain ever vigilant and continue to find ways to improve our ability to predict these natural cosmic hazards."

The unveiling of NASA's new system comes just a day after ESA officials confirmed that the agency's Hera mission, launched in October, will study the asteroid Didymos and its moon Dimorphos, which was struck by NASA's Double Asteroid Redirection Test (DART) mission in 2022 in a test of technology that could be used to divert hazardous asteroids.

The Hera mission will also test technology that could be used to place satellites in orbit around dangerous asteroids to monitor them and provide early warnings of potential collisions with Earth.

Scientists estimate that an asteroid strike on Earth occurs once every 1,000 centuries or so.

Roughly once every 100,000 years, an extinction-level event is believed to occur.

Over the course of millions of years, these events have helped shape Earth and altered the trajectory of life on the planet.

With NASA's new system, scientists will have a better idea of when the next one will occur and how best to prepare.