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cover of the September 8, 1973 of Science News

Searching for superheavies — Science News, September 8, 1973

Physicists and chemists have been actively searching for superheavy elements, substances with atomic weights and numbers greater than the 105 [elements] now known. Results of two searches are reported … none were found…. Future searches will have to involve direct fusion of heavy nuclei by driving one against another in heavy-ion accelerators.

Update

Particle accelerators have been crucial for creating superheavies beyond elements 104 and 105. Just a year later, element 106, seaborgium, emerged from collisions of oxygen ions and californium atoms — though its discovery wasn’t officially confirmed until two decades later (SN: 3/19/94, p. 180). Elements 107 through 118 have since made their debut, with several joining the periodic table as recently as 2016. Scientists are now trying to create elements 119 and 120 (SN: 3/2/19, p. 16). Forming heavier elements and pushing known superheavyweights to their limits could reveal insights into the forces that bind atoms together and the bizarre chemistry of the most extreme elements.



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