In Black in Blues, Imani Perry reaches to the height of the sky and the depth of the ocean, casting the history of blue as one of both triumph and tragedy, possibility and limitation.

Dark matter is more than five times as abundant as all the visible matter in the universe. So why can't we see any of it?

Radiation within the visible spectrum can appear black if it is low in power – more specifically, lower in power than its surroundings. Additionally, radiation outside the visible range of wavelengths ...