|Ned Flanders' credit card doesn't satisfy the Luhn checksum, |
but could probably still be erased by a magnetar.
A while ago I heard that a magnetar can erase all the world's credit cards from half the distance to the moon. I did a little research and it seems like this is the go-to "fun fact" about magnetars. Almost every time they are brought up in a popular science article, their credit card-erasing prowess is sure to get a mention. So let's check it out!