Today is the 100 year anniversary of the Tunguska meteor impact. If you don’t know why this is important, I suggest you read “Rain of Iron and Ice” by John Lewis. I own a copy so if you’re ever in town, you can borrow it. It’s one of my books that doesn’t get loaned.*
If the Tunguska impactor had hit 8 hours later, it would have obliterated St. Petersburgh, Russia. That’s a reason to care.
*I don’t “loan” books anymore. It’s like money: if you’re so hung up about getting things back, you will sour the relationship with the friend/family member/random schmoe that you loaned the book to. Just give it away and maybe they’ll give it back. If they’re not someone that you would want to give books (or money) to, then why are you?