We have a great question from our facebook so let us go ahead and: Ask ARSE.
"Why do all the good-sized asteroids keep missing us?" asks Michael McMahon.
Well Mitchell, a good question with some numbers and recent news behind it.
Asteroid 2006 QV89 is a quaint 40 meter in diameter rock which is expected to whiz by us on September 10th.
We say it is quaint as the asteroid that wiped out the dinosaurs 66 million years ago was a bulky 10 kilometres wide.
The asteroid will bypass earth at around 6.7 million km away and the odds of 2006 QV89 hitting us is estimated at around 1 in 7300.
So these numbers are pretty much what you can expect on a "good day" for any object to hit us, not counting size.
So let's define "good-sized" before we probe any further.
An asteroid the size of 2006 QV89 would do minimal catastrophic damage.
An object roughly 1.5km in diameter would excavate more than a trillion tonnes of material into the atmosphere and scatter it over an area the size of Europe. This would affect the global climate and degrade crops and cause a general loss of life. This occurs perhaps once every million years.
Once every 50-100 million years an asteroid 8km in diameter is projected to strike the earth and while this is 2km smaller than the one that caused the mass extinction of the dinosaurs, it is more than sufficient to end life on earth as we know it.
The minimal required size for an asteroid to end life on earth is expected to be 5km wide, just half the dinosaur killer.
From our best estimates, we can tell that the only "good-sized" asteroids are around 15 in number that will pass by earth yet we would have to be very patient waiting for them.
As in millions of years.
Thank you for your question Mitchell and thank you for helping spread ARSE further as we join hands and thrust into the deep unknown...
#Space_Aus
So there you have it, the reason why the good sized
