how big an impactor

are we extreemly lucky that nothing like this has happened to us thus far, or are the odds of such a cataclysmic event happening in our backwater part of the galaxy/universe extraordinarily low?

I dont mean this exact instance, but this, or a supernova close by, or a blackhole wandering in our direction or something else on that scale?

Collisions never ever occur out here in the empty Galactic sticks.

Collisions are common in Globular Clusters, producing peculiar stars known as "Blue Stragglers":

www.solstation.com/x-objects/bluestrag.htm

are we extreemly lucky that nothing like this has happened to us thus far, or are the odds of such a cataclysmic event happening in our backwater part of the galaxy/universe extraordinarily

Jeeze, if you did a search like I did on "asteroid impacts" and looked at the search results, many, many objects are out there with known orbits that come close to Earth. And then you've got the ones that were discovered either 2 or 3 days before passing to even a day or 2 afterwards! Some of them within a missile strike of Earth! :shock:

Seanie.

We are not as smart as we think we are when it comes to tracking NEO's (despite hollywood blockbusters). There are probably objects out there that we would never see coming. On the other hand the proof is in the pudding. we have been lucky that within historic times no major event has occured that would endanger whole species.

The sun will never be hit by another star, the distance scale is too vast.
(It the sun measured one inch in diameter the nearest star would be 475 miles away.)
We will be safe from direct collision even when the Milky Way and the Andromeda Galaxy collide head-on in around 3 billion years:
en.wikipedia.org/wiki/Andromeda-Milky_Way_collision

Frank Summer's simulation of that event:
www.cita.utoronto.ca/%7Edubinski/Gravita...ralMetamorphosis.mov

(The sun may be flung out of the galaxy into inter-galactic space by gravitational forces, but it won't be hit directly by another star.)

typically, the objects discovered ages days before or after their close shave with earth are small - of the order of 10's of meters. They are hard to discover because of their lack of brightness. Hardly of a size to cause global catastrophe but I personally would subscribe to the NIMBY view...

Larger rocks are easy to find ahead of time because of their "brightness"

Dave