It’s going at 68km/s so I think even microbial life could be in trouble.
You could very well be right!
Seems like it arrives with a bit more energy than a 10 on richter scale: https://www.edinformatics.com/inventions_inventors/richter_s...
No, I can’t really imagine what that means, either.
An object (depending on consistency) of about 100m is enough to wipe out a city and do enough damage to the environment. Something of 8-20km is in the same category as what wiped out the dinosaurs (10-15km).