Reasoned intellects have anagrammed Nabiru as...

"Numberless Idiots believe in ridiculous urban-myths"

When someone proclaims "I believe in Nibiru" pat them on the head,
see them safely across the street,
& give them a cookie...

Maybe better for the gene pool to get them 1/2 way across the street, give them a cookie, & tell them to wait there, you'll be right back