DJohnM 8 years ago

Can't you just take the nine (eight?) planet names and look for each in an alphabetic list of the elements?

Envite 8 years ago

This question appears to be off-topic because it shown no previous investigation AT ALL.

RhysW 8 years ago

This question appears to be off-topic because it is not within the scope of this site and shows no attempt at prior investigation.

Keith Thompson 8 years ago

If you're going to count dwarf planets (Pluto/Plutonium), you should also count Cerium, which was named after Ceres (which was still classified as a planet when the element Cerium was named after it).