dataset: available on kaggle, dataset name: Possible Asteroid Impacts with Earth
Asteroid: a large rocky object in space, in orbit around the Sun.
Meteoroid: smaller rocks in orbit around the Sun.
Meteor: If a meteoroid enters the Earth's atmosphere and vaporizes, it becomes a meteor, which is often called a shooting star
Meteorite: Some objects are big enough to survive the passage through the earth's atmosphere and hit the Eath's surface.
Is it likely that life on earth would be destroyed by an asteroid impact?
The likelyhood of an extinction event depends on the energy released during impact, which in turn depends on the mass (which is related to the size and density) and the velocity.
In general it is estimated that an object of 10km diameter or larger would result in many deaths and would release enough dust into the atmosphere to cause a 'nuclear' winter. Resulting in widespread famine. A 10 km object would probably not cause the complete extinction of the human race but it would probably result in the breakdown of civilisation.
What is the diameter distribution within the dataset?
So most of the objects in this dataset are about 10m or less in diameter.
Are there any objects greater than 1 km?
The three largest objects are:
2010 AU118 = 1.9 km
2011 SR52 = 2.579 km
29075 (1950 DA) = 1.3 km
None of these objects is big enough to cause the extinction of the human race. That's the good news, the bad news is that the dataset only includes some of the asteroids that have been discovered, there may be many more that remain to be discovered and some of those may be larger than 10km.