Selenium
Element #34 with the symbol Se. Selenium usually comes as a smooth, black, glossy solid, like a chunk of sexy chocolate. It can also occur as a red powder, which is much more reactive than the black counterpart. Selenium has many applications in today's world, such as being a key ingredient in vitamin supplements and shampoos, solar cells, photoconductors, batteries, fertilizers, and glass production. One property unique to Selenium is that it is quite sensitive to light. This strange characteristic paved the way for the development of solar panels and other devices that utilise light/electricity. Selenium gets its name from the Greek "Selene", which means "moon". The reason for this is because at the time of its discovery, Selenium was placed directly above Tellurium on the periodic table. And Tellurium's name was derived from the Latin "Tellus", which meant "earth". It made perfect sense to name an element after a celestial body with correlation to another similarly-named element.
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