Cosmic Connections is a series that explores how our experiences here on Earth aren't so different across the universe. Lasers are some of the most fantastic inventions to come out of twentieth-century labs. Due to various and very important (and very much the subject of another article) rules of the quantum mechanical universe, electrons can only exist in fixed, discrete distances around a nucleus. That’s why lasers have incredibly specific colors: their innards are filled with a uniform gas. We can make lasers here on Earth, and in fact the first lasers operated not at visible wavelengths but in the microwave – they were known as MASERS.

Source: Forbes February 10, 2019 01:41 UTC