When the Apollo 11 astronauts landed on the moon in 1969, they left behind a white pouch containing a silicon disc slightly bigger than a silver dollar. Inscribed in microscopic font on the disc are 73 messages, each from a different country, expressing wishes of goodwill and peace.
Silicon isn't the same thing as silicone, that famous polymer found in breast implants, menstrual cups and other medical technology. Silicone is made of silicon along with oxygen, carbon and hydrogen. Because it resists heat so well, silicone has increasingly been used to make kitchen tools, such as oven mitts and baking sheets.
Silicon can be dangerous. When inhaled over long periods of time, it can cause a lung disease known as silicosis.
Love the iridescence of an opal? Thank silicon. The gemstone is a form of silica bound with water molecules.
Plants use silicon to strengthen their cell walls. The element appears to be an important nutrient that helps confer resistance to disease, according to a 1994 paper in the journal Proceedings of the National Academy of Sciences.
Silicon Valley gets its name from the silicon used in computer chips. The nickname first appeared in 1971 in the newspaper "Electronic News."