Why NASA deliberately collided with an asteroid in its quest to protect Earth?

On September 26 of this year, a NASA spacecraft the size of a refrigerator plowed with an asteroid. 

This was an intentional act on our part.

This isn't the premise of a film. 

 After 10 months in orbit, NASA's Double Asteroid Redirection Test (DART) .

Successfully redirected the route of the asteroid Dimorphos by impacting it at over 14,000 mph. 

This was the first test of planetary defense technology.

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NASA will make another go at a lunar launch.

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