For an asteroid to wipe out humans, it has to be bigger than the one that killed the dinosaurs

• For an asteroid to actually destroy life on Earth, it will have to be bigger than the one that caused the dinosaurs to go extinct.
  
• The fact that humans are smarter gives them an edge over the dinosaurs when it comes to detecting and avoiding extinction level events — like an asteroid impact.
  
• It would still be a set back for human history where people would either have to hide deep underground or survive eating shellfish.
  

A large number of asteroids are hovering all around the Earth, and we might get hit too sooner or later. But it will not be the Armageddon that everyone fears or the end of human life as we know it.

"In the order of things people should be worried about, Near Earth Objects isn't highest on the list," states Lindley Johnson, the Planetary Defence Officer for the National Aeronautics and Space Administration in the recently published book End Times.

"But it does have the potential to be the most devastating natural disaster known to man," explains Johnson.

And, it's only a matter of time.

"It's a 100% certain that we're going to get hit, but we're not 100% certain when," B612 President Danica Remy told NBC.

Humans survived when the Sun was blocked out

There is evidence that a kilometer long asteroid crashed into Southeast Asia around 800,000 years ago — and our ancestors had survived it.

The asteroid did impact human evolution and blocked out the Sun for years with the dust it threw up. Yet, humanity was not wiped out.

Scientists are yet to determine exactly how humans managed to survive and they're hoping that finding the exact impact site of the crater will help.

Humans are smarter than dinosaurs

The fact that humans are smarter than dinosaurs gives them an edge when it comes to surviving an asteroid impact.

"So long as we retain at least stone age technology, there isn't much that could make us extinct," Robert Walker, a scientist and mathematician, told Science 2.0.

It's possible that humans would go back to beach-combing or surviving on shellfish but they would survive, according to Walker.

Another way to survive an asteroid impact would be to go deep underground to survive what would be a nuclear winter — similar to what follows a nuclear war, according to Elisabetta Peirazzo, a senior scientist at the Planetary Science Institute.

NASA is working on a mission to survive asteroids

As of now, there are a lot of asteroids whizzing past Earth — some of them a little too close to comfort — but none are on a direct collision course for the planet according to NASA's Planetary Defence Coordination Office (PDCO).

If an asteroid were to shift its course, space agencies have telescopes on ground and in space, keeping an eye out.

NASA is currently working on its Double Asteroid Redirection Test (DART) Mission to defend the planet against any extinction level asteroids that might come its way.

See also:
It might not be 'dinosaur destroying' but it's only a matter of time before an asteroid hits Earth

Another pair of asteroids is going to whiz past Earth on 14 September — Bigger, faster but further away

An asteroid only turns into a meteor if it falls to Earth

What happens when an asteroid actually hits Earth