The Search for the Final Element

Identifying Every Different Kind of Atom that Could Theoretically Exist in the Local Universe

Joshua Hehe
6 min readMay 30, 2021

Early in the 19th century, a pioneering chemist named Johann Wolfgang Dobereiner noticed that certain chemical properties repeat when the elements are placed in order of increasing mass. That is to say, halogens, alkaline metals, and alkaline earths always occurred in the same order. Then, once Dobereiner’s pattern was established, another trailblazing chemist, named Dmitri Mendeleev, tabulated the sixty-one elements that were known at the time. This helped set the stage for modern-day chemistry.

It did this by allowing Mendeleev to see blank spaces where other elements should exist. This gave him the ability to predict undiscovered atoms on the old vertical row model, setting him apart from everyone else in his field. As if that wasn’t impressive enough on its own, in 1871, Mendeleev rearranged the elements, putting the ones with similar chemical properties in the same vertical columns. That one simple act totally revolutionized chemistry from that moment on, because the resulting chart became the classic periodic table of elements.

The question is if hydrogen is the first element on the list, then what will the last element be? What’s the heaviest possible superheavy element that…