Video: Every Asteroid Tracked By NASA Over the Last 20 Years

It might seem like more asteroids than ever are making their way through our solar system. In the last few months, plenty of space rocks have zipped past our planet—and some have even made impact.

But in reality, astronomers have become an awful lot better at tracking asteroids, as a new NASA video (above) marking the 20th year of the agency's Center for Near Earth Object Studies (CNEOS) shows.

The space agency has released a simulation of all asteroids logged with CNEOS since it started tracking the space rocks as the Near-Earth Object Observations Program in 1998. Depicted as dots spinning through our solar system, you can see the number of space rocks balloon over the decades as tracking technology improved.

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An asteroid belt is pictured in this artist's impression. Getty Images

"We compute high-precision orbits for all asteroids and comets and map their positions in the solar system, both forward in time to detect potential impacts, and backward to see where they've been in the sky," Paul Chodas, CNEOS manager, said in an agency statement.

The Near-Earth Object Observations Program was launched to fulfill a request from Congress, to track and log 90 percent of all asteroids and comets larger than two-thirds of a mile, whose orbit draws them into the inner solar system, within a decade. The program was renamed CNEOS in 2016.

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The animation depicts a mapping of the positions of known near-Earth objects (NEOs) at points in time over the past 20 years, and finishes with a map of all known asteroids as of January 2018. JPL-Caltech/NASA

The launch of the program followed a media frenzy spurred by a half-mile-wide asteroid called 1997 XF11, NASA reported. Soon after astronomers spotted the asteroid, they notified the scientific community that there might be a chance it was on a collision course with Earth.

Other astronomers initially agreed, fearing there was a slim risk the rock might smash into our planet in 2028. News outlets ran with the story and spread an ominous message of doom, the Washington Post reported last year.

Further calculations showed Earth was safe, but the saga highlighted a need for better asteroid tracking—and clearer public communication.

"To this day we still get queries on the chances of XF11 impacting in 2028," Chodas said. "There is simply no chance of XF11 impacting our planet that year, or for the next 200 years.

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The chart depicts the cumulative number of known Near-Earth asteroids (NEAs) versus time. JPL-Caltech/NASA

Although XF11 isn't dangerous, other asteroids have caused mass destruction on Earth. An asteroid thought to measure about 70 feet across damaged thousands of buildings after it entered the skies above Chelyabinsk Oblast, Russia, as a meteor in 2013. A shockwave from the impact blew out windows and led to almost 1,500 injuries.

Tracking potentially dangerous asteroids is therefore crucial to planetary protection. The earlier astronomers spot an asteroid, the sooner they can work on addressing it. Just last month, NASA announced a five-goal strategy to improve Earth's space rock defenses.

Even though astronomers are detecting far more asteroids than they were back in 1998, the technology is still not perfect. Just this month, two small asteroids buzzed Earth undetected, only to be spotted after they'd zipped past our planet.

NASA did not immediately respond to a request for comment.