October 2019    
  Shell game  
  Scientists are making new elements, and they're super heavy.  
  In 1869 Dmitri Mendeleev discovered the organizing principles that inform our modern periodic table. Now, 150 years later, we celebrate the International Year of the Periodic Table of Chemical Elements. The map of all known materials looks a lot different than it did back then.  
  Let's take a quick trip back to middle school: the periodic table arranges elements horizontally in order of the number of protons in the nucleus and vertically by shared properties. For example, helium, neon, argon, and other elements in the far-right column are the noble gases; they're highly stable because their outermost electron shells are full.  
  Scientists think they know all the elements found (or detectable) in nature, and they're now creating new ones in the lab by slamming atoms together and fusing their nuclei to form "superheavy" elements. But these exist for mere milliseconds. They're so unstable because positively charged protons repel each other. As the number of protons rises, that force grows until the nucleus tears itself apart.  
  But there's a fabled "island of stability" of hypothetical superheavy elements that would be stable for an extended period--possibly billions of years. That stability would come from a particular number of protons (or neutrons) in a certain nuclear arrangement.  
  Remember those stable noble gases with their full electron shells? There are also shells inside nuclei, and when those layers get filled by protons or neutrons, the nucleus holds together in a superstrong bond.  
  The nuclear shell model was discovered by Maria Goeppert Mayer in 1948 while she was employed at the University of Chicago's Institute for Nuclear Studies and Argonne National Laboratory. The discovery, for which she shared the 1963 Nobel Prize in Physics, included the existence of "magic numbers" that correspond to full nucleus shells and high stability.  
  Because Maria Goeppert Mayer's husband held a faculty appointment at the University of Chicago, she was prohibited from working in the same department by the University's antinepotism rule. She conducted her Nobel-winning research as a volunteer professor. (UChicago Photographic Archive, apf1-04170, University of Chicago Library)  
  If a nucleus has a magic number (2, 8, 20, 28, 50, 82, or 126) of either protons or neutrons, it should be stable. If a nucleus has a magic number of both protons and neutrons, it's "doubly magic."  
  So far the periodic table contains 15 superheavy elements, ranging from 104 to 118 protons. As scientists add more and more mass, gaining on the next magic number, they think they can see the island of stability on the horizon--maybe they've already touched the shore.  
  Positive gains  
Manhattan Project chemist Glenn Seaborg codiscovered 10 elements and held the patent for the elements americium and curium.
In 1922 UChicago chemists developed an apparatus to decompose tungsten into helium. The Associated Press claimed they achieved transmutation. They had not.
A Nature article celebrating the women behind the periodic table describes how technician Toshiko "Tosh" Mayeda mastered the measurement of oxygen radioisotopes in the 1950s. Her initial responsibility was washing glassware for UChicago chemist and Nobelist Harold Urey.
UChicago chemists separate different isotopes by treating them like atomic-sized bouncy balls.
  Pure poetry  
  In 2017 Science magazine published an interactive poetic periodic table that fuses science and art with positively satisfying results.  
  Each element is given its own haiku, a traditional Japanese poem consisting of three unrhymed lines of five, seven, and five syllables. The series ends with a haiku for the as-yet-unrealized element 119: ununennium.  
  In case you missed it  
Neutrino news: DUNE gears up to search for ghost particles.
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