There are no longer any questions on the main site tagged with earth. Discussion has taken place here and consensus is that the earth is not a useful tag. This site is titled "Earth Science" and that implies every question is inherently about earth, so the tag is unnecessary and conveys no useful information. Yes, other planets and their processes are on-topic (here and here) for this site, and for those questions it is appropriate to use a tag that conveys that they are not about earth, but no such need exists for questions about earth.

Perhaps most detrimental to earth is that alone it tells us nothing useful about a question and this makes it a bad tag.

I am proposing that we blacklist earth so that it may no longer be used on this site.