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Is NASA Aware of Any Earth-Threatening Asteroids?

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We Asked a NASA Scientist.

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No, there is no asteroid that we know of
that is concerning in terms of impact hazard.

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Now, we know that asteroid impacts have
happened in the past

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and can certainly happen in the future.
But we should keep in mind that those are rare events.

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An asteroid impact that could cause serious regional damage

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only happens every few thousand years or longer.

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Still, it's a good idea to protect us against 
that possibility and the rule of the game is

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find asteroids before they find us.

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And that's why for over 20 years, NASA has been funding
search programs to observe the sky

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pretty much every single night to find
and track asteroids.

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And we've been doing a pretty
good job at that. So far, we've discovered

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more than a million asteroids, including
95 percent

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of the asteroids that are greater than
one kilometer and that could come close to the Earth.

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Once we discover an asteroid, we project its motion into the future

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to assess the possibility of an impact with Earth.

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We have a scale called Torino scale that
helps us rank the risk coming from each asteroid.

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It goes from zero, which is
lowest risk, to 10, which is highest risk.

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And the good news is that for all the asteroids that we've

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discovered so far, the Torino scale is zero —
so, lowest risk for the next hundred years.

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So, is NASA aware of any Earth-threatening asteroids?

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No. But we will keep searching the skies just in case.