A giant leap toward protecting the Earth

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For some people, it probably wasn’t earthshaking news – and if all goes as hoped, that will be the point.

Last week, a NASA probe crashed into a small asteroid, but the impact was intentional. And in a few weeks, we will know if it made an impact of a far more important nature.

The probe was called DART (Double Asteroid Redirection Test), and it was designed specifically to intercept an object in space to determine if a crash impact could alter its trajectory. The effort is part of a loftier goal of enhancing earth’s defenses against possible asteroid strikes that could have catastrophic consequences for the planet.

The $325 million DART mission was humanity’s first attempt to alter the path of a space object – in this case, a football-field sized rock called Dimorphos, which was sailing past Earth about 6.8 million miles away. The probe hit the asteroid very close to its intended target, an accomplishment which itself brought cheers from NASA officials.

Whether the impact of the small probe could move a 5.5-billion-ton object will not be known for several weeks. But even a minute change in course would represent a major step forward in protecting the planet.

As stated at the top, some people will dismiss this mostly as something more closely akin to science fiction and fantasy – or movies like “Deep Impact” and “Armageddon” – than pressing news.

It represents a lot more than that.

First, it must be acknowledged that the chances of the Earth being struck by such objects are mathematically remote. Right now, scientists say there are no known objects that appear on a trajectory to hit the planet in the next century. But that comes with a big caveat: It’s estimated that only 40% of those potential asteroids have been discovered.

Secondly, asteroids have hit the Earth in the past. Scientists believe a massive impact 65 million years ago in what is now Mexico may have led to the extinction of dinosaurs, as well as 70% of all life on Earth. That object was estimated as being up to 9 miles long, but many smaller objects – even one the size of Dimorphos – could have major consequences, such as suffocating dust plumes, tsunamis and devastating earthquakes.

If we have successfully taken our first step toward establishing a planetary defense, it’s game-changing news. Lori Glaze, NASA’s planetary science division director, said DART’s success marked a “new era of humankind,” adding: “(It’s) an era in which we potentially have the capability to protect ourselves from something like a dangerous, hazardous asteroid impact.

“What an amazing thing. We’ve never had that capability before.”

And that’s overwhelming news – even if it’s a system we hope we never have to use.