title: Asteroid Impact
Probability of an Asteroid Impact

The largest asteroids will cause the most damage but there are less of them. Astronomers have used mathematical models and historical data to estimate the probability of an asteroid hitting the earth.

 

 

Size
Number near Earth
Frequency of impacts
Last impact
Annual probability of impact

10 - 50m


2 hundred million

1 in every 5 years

Siberia, 1908: area not populated.

0.2

100m

2 hundred thousand

1 in every thousand years

China, 1490: 10,000 deaths

0.001

1-2km

2 thousand

1 in every 100,000 to 1 million years

Argentina, 3 million years ago: local extinctions and global cooling

0.00001

15km

50

1 in every 65 million years

Mexico, 65 million years ago: dinosaur extinction

0.00000002

 

 

Even though the largest asteroids could cause mass extinctions, the likelihood of one hitting the earth is almost negligible. Smaller asteroids are more likely to impact and so are more of a risk.