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The periodic table as we know it now seems complete, its current 118 elements nicely fitting in the seven familiar rows. How many more can be synthesized — and how will the table expand to accommodate them? The search for ever-heavier elements is pointing towards new periods, though perhaps not as neatly ordered as the first seven.
Scientists and non-scientists alike have long been dreaming of elements with mighty properties. Perhaps the fictional materials they have conjured up are not as far from reality as it may at first seem.
At its inception, the periodic table sorted elements by weight, so it may be surprising that the heaviest natural element on Earth remains controversial, or at best, nebulous. In the strange, perhaps-unfinished search for this weightiest nucleus, the only definitive conclusion is that it lies somewhere beyond uranium.
