It’s a nightmare scenario for humanity: an asteroid, or asteroids, barreling toward planet Earth.

The impact vaporizes everything even remotely nearby and devastates civilization for thousands of miles around.

Even those who survive are subject to a new era of natural disasters. Clouds of dust block out the sun’s light, creating multiple years with no summer. Agriculture takes a nosedive as grain can’t ripen and livestock starve for lack of forage. Governments collapse and despots seize power amid the chaos.

The event would be one of the most defining and impactful in natural human history.

Thankfully, this is just a “what if” scenario.

Despite the slim chances of it ever happening, NASA is preparing for this exact catastrophe with a test of our planet’s final defense system.

The agency has identified two asteroids that pass close by Earth but pose no immediate threat. According to The Washington Post, a SpaceX Falcon 9 rocket will be launched at the smaller of these on Nov. 24 in an attempt to change its trajectory.

That’s right. NASA is going to slam a rocket into an asteroid.

The Double Asteroid Redirection Test, or DART, aims to adjust the asteroid’s path by only a fraction of a percent.

While this may not seem like much, it could mean the difference between an impact and a near miss.

After being launched from its California base, a spacecraft will detach from the rocket and make its way to the asteroid before hitting it at a blistering 15,000 mph.

Don’t expect to watch this collision from your front porch — or any time soon.

The spacecraft will travel for over a year to meet the asteroid some 6.8 million miles from Earth.

An impact is expected in September of 2022 if everything goes according to plan.

We won’t be completely in the dark. A satellite will accompany the DART craft and record the impact, letting terrestrial scientists know if the test is successful — or if humanity should start working on plan B.

Their preparations notwithstanding, NASA experts don’t foresee any immediate threat to our planet.

While this plan may seem like something out of a science fiction movie, it’s nice to know that any asteroid hurtling toward Earth can expect to meet an American rocket face to face.