This is cool, but scary too.
There is a website called killerasteroids.org which lets you simulate asteroid strikes on Earth.
Is it genuinely backed up by scientific calculations? Dunno, but it's fun.
We tried it out on Cork city and a small asteroid about the size of a bus going at 20km a second would take out the city centre and do a fair bit of damage to the outskirts.
A medium-sized rock would inflict first-degree burns throughout the whole rebel county, but frighteningly, a large, 2km wide, asteroid would mean curtains for the whole country, and would even affect the UK. Gulp.
So if you wanted to find out the extent of the damage from asteroid that is passing by tonight, go to their impact simulator and, click on "custom location" and type in the name of your home town.
But don’t worry, according to Nasa the closest it will get is about 17,000 miles.
So, if you are out tonight with your binoculars or telescope, keep your eye on the plough at about 9.30 and thank the stars for the near-miss.