OH Look! There's a great big..........
BLAAAMM!
In the early hours of Saturday morning an asteroid whizzed past Earth at what in astronomical terms a very close shave, skimming just 186,000 miles over our planet's surface. Asteroid 2014 HL129 squeaks past Asteroid 2014 HL129 squeaks past The asteroid, dubbed 2014 HL129, a 4-to-15 meter-wide chunk of space debris, …
According to this impact effect calculator: http://impact.ese.ic.ac.uk/cgi-bin/crater.cgi?dist=0.1&diam=15&pdens=3000&pdens_select=8000&vel=51&theta=90&tdens=2750&tdens_select=0
It would break up into fragments and would not leave a significant crater. This is assuming that it is made of Iron, travelling as fast as a comet and impacting @ 90deg or straight through the shortest part of the atmosphere (the worst case).
Not even a megaton of energy energy in the airburst.
I don't know what the source is for this but perhaps it assumes we have no atmosphere to protect us. Not really that newsworthy if you ask me.
Sure. But if ground zero were, in some unlucky event, not to be some sparsely populated area, but in or dangerously near a city, you might be able to get the people away, ... but where would they all go? Solvable, no doubt, but I suspect the implementation of whatever evacuation plan there might be would turn into a giant disaster of its own, .. even if the asteroid itself turned out to be something of a non-event.
Also relevant, it seems that if an asteroid hits the Moon it could cause a lot of damage due to (a) shifting of its orbit and (b) fragmentation of the Moon which could occur really easily if the asteroid was say 10* as big as the K-T impactor and moving just a little bit faster.
Even knocking a chunk of the Moon off would be very very bad.
We demand Spaceguard, and we demand it NOW!!!!
On the flip side, the AGW crowd will be hiding in bunkers like the rest of us come 2047 if Apophis hits because the eejits in Govt funded Gulf War III: Revenge of the Sith instead of Spaceguard.