I assume it's a placeholder for when there's no location data.

Friggin Earthlings always assuming everyone on the Internet is human.

iirc it's one of the first things elon changed where it used to say which client you were posting from because elon got tired of people ragging on him for attacking apple while posting from an iphone

It's like people from parallel universes are on the internet. They must call their version of Earth something else where they're from. =p