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When Was the Last Time an Asteroid Hit Earth?

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We Asked a NASA Scientist.

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Well, the answer depends on whether you're\h
asking about small or large impacts.

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Because Earth gets hit all the time. But luckily\h
for us, the vast majority of these impactors are

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small and they just burn in the atmosphere. The\h
most significant fireball event in over 100 years

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occurred over Russia in 2013. We actually got\h
hit by an asteroid that was the size of a small

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building and that one disintegrated about 20\h
kilometers above the city of Chelyabinsk.

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And it deposited a fair number of meteorites in\h
the ground and I happen to have a piece of the

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Chelyabinsk impactor right here\h
in my hand. But what about big impacts,

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the ones that leave craters tens of kilometers\h
wide and cause huge amounts of devastation?

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We have to go far back in time for such an\h
event and those old craters are not easy to spot

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because by now they're heavily eroded, they're\h
filled with sediments, or they can be at the bottom\hof the ocean.

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But to keep the long story short,\h
small impacts, they happen all the time, especially

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given that about 15,000 tons of space dust hit\h
Earth every year. And large impacts are rare, and

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we're talking millions of years rare. So, when was\h
the last time an asteroid hit Earth?

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Probably today,\hbut the odds are it was very small\h
and just burned in the atmosphere.