|Fig. 1: Periodic Table (Source: Wikimedia Commons)|
The elements we see on the periodic table constitute much of the matter that we can see, as seen in Fig. 1. Scientists, up to this day, are continuing to discover new elements in the laboratory. It takes lots of patience and many years to find these elements, and some synthesizing, as some of the newly discovered elements don't naturally occur. But the research gives us new insights into atoms and elements, and possibly unexplored elements will continue to be found and expand our knowledge of the world around us.
Near the end of 2015, four new elements were discovered, gaining the elemental numbers of 113, 115, 117 and 118. They were given temporary names until they will be formally named later. A team of Russian and American scientists discovered three of the elements, and a Japanese group found one. As with most recently discovered elements, they were only observable in laboratory conditions and wouldn't be found in our everyday world. The element that the Japanese team discovered existed for less than a thousandth of a second, showing the extremely short life spans that some of these particles can have.  The short life span demonstrates the instability of the isotopes, as they can exist for such short periods of time before vanishing.  Even after finding the element, it took them 7 years for them to prove that it actually existed in that fraction of time through rigorous laboratory experiments. Similar to newfound elements, elements can exist in different states based on their atomic number, such as helium-3 and helium-4 being isotopes of each other, or having different masses due to different neutron numbers. These isotopes can have similar properties but very different characteristics.
Unstable isotopes have many possible applications to our lives. Firstly, an isotope of cobalt is used in medicine to stop the spreading of cancer. Radioactive isotopes can be used as tracers in patients to monitor various internal processes. An isotope of iodine has been used to find brain tumors. In addition to medicine, in industry, unstable isotopes have can measure the thickness of metal, or using them for electricity power, such as uranium or plutonium sources. However, these isotopes can be dangerous in high dosages and difficult to store, so it is extremely important to limit or completely discourage contact with these isotopes. Certain isotopes can also have very high energies and release lots of it when decaying, creating a possibly destructive danger. 
Unstable isotopes are fascinating. Whether they occur naturally in only in the lab, humans have been able to extract key features of these isotopes for our use. As we learn more about these strange elements, we will be able to harness their powers further. However, we must be careful of their risks, as unstable isotopes pose potentially devastating side effects. We must be diligent about safety while exploring and unveiling these incredible particles.
© Brandon Sutter. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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