For 10 points, name this color that names "holes" from which not even light can escape.
Vertically aligned nanotube arrays have been used to produce the most intense known form of this color. The Lyman absorption forest is formed by lines of this color emitted by quasars. This color describes objects that can be approximated by a cavity in a hole and have an emissivity of one. This is the color of spectral absorption lines, as well as the background of an emission spectrum. The Rayleigh-Jeans law describes radiation from bodies named for this color. Gravitational collapse can form an object named for this color, which has a Schwarzschild radius that marks its event horizon. For 10 points, name this color that names "holes" from which not even light can escape.
Vertically aligned nanotube arrays have been used to produce the most intense known form of this color.
black [prompt on no color or equivalents]