Black body

A black body is an object that absorbs all electromagnetic radiation, or all colors of light. It emits electromagnetic black-body radiation at Planck scales.

A black hole absorbs all the light that hits its event horizon, reflecting nothing, making it almost an ideal black body. Hawking radiation is black-body radiation that is released by black holes because of quantum effects near the black hole event horizon.

The universe approximately a second after the Big Bang was a near-ideal black body at a temperature around 1010 K. The cosmic microwave background radiation (CMBR) observed today is a perfect black body.

Vantablack is a material that absorbs up to 99.965% of visible light. The name is a portmanteau of the acronym VANTA (vertically aligned nanotube arrays) and the color black.

The world's closest white body is a paint that reflects 98.1% of solar radiation while emitting infrared heat.

Max Planck modeled the cavity walls of black bodies as a collection of tiny electromagnetic oscillators. He posited that the energy of oscillators is discrete and could assume only certain values. These oscillators both emit energy into the cavity and absorb energy from it via discrete jumps, or in packages called quanta. Planck’s quantum approach involving discrete oscillator energies for theoretically deriving his Blackbody Radiation Law led to his 1918 Nobel Prize.