Do Not Confuse Dark Energy With Dark Matter T-Shirt

No need to be an astronomer or astrophysicist -- although it would certainly help -- to understand the difference between dark energy and dark matter. Dark energy is a hypothetical form of energy that permeates all of space and tends to increase the rate of expansion of the universe. Dark matter is matter that is inferred to exist from gravitational effects on visible matter and background radiation, but is undetectable by emitted or scattered electromagnetic radiation and is hypothesized to account for discrepancies between measurements of the mass of galaxies, clusters of galaxies and the entire universe made through dynamical and general relativistic means, and measurements based on the mass of the visible "luminous" matter these objects contain: stars and the gas and dust of the interstellar and intergalactic medium. Got that? Showcase your wry dark energy and dark matter attitude with this educational, astronomical tee featuring a pie chart of the Universe and what it consists of!