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Here’s What You Need to Know About Near-Earth Objects

Our solar system is littered with asteroids and comets, and sometimes they get a little close to Earth. But no need to worry! This happens all the time. When an asteroid or comet could come close to our planet, it’s known as a near-Earth object – aka NEO.

But how close is “close”?

A near-Earth object is defined as an object that could pass by our Earth within 30 million miles. We begin to keep close watch on objects that could pass within 5 million miles of our planet.

To put that into perspective, our Moon is only 238,900 miles away.

However unlikely an impact is, we want to know about all near-Earth objects. Our Planetary Defense Coordination Office maintains watch for asteroids and comets coming close to Earth. Along with our partners, we discover, catalog and characterize these bodies.

But what if one of these objects posed a threat?

We want to be prepared. That is why we are working on several deflection techniques and technologies to help protect our planet.

So next time that you hear of an asteroid passing “close” to Earth, know that it’s just one of many that we are tracking.

Here are 10 more things you should know about Planetary Defense.

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