No, pulsars can have a range of colors, including black, but they are not limited to that color. In fact, the color of a pulsar is not directly related to its properties or characteristics. Pulsars are highly magnetized, rotating neutron stars that emit beams of electromagnetic radiation. These beams can be observed across the electromagnetic spectrum, including radio waves, visible light, X-rays, and gamma rays.
The perception of color depends on the wavelength of the electromagnetic radiation. For example, if a pulsar emits predominantly radio waves, it may appear as a radio source and not exhibit any visible color to the human eye. However, if the pulsar emits radiation in the visible light range, it could appear as a point of light with a particular color, depending on the specific wavelengths emitted.
The color of a pulsar, therefore, depends on the properties of its emission and the detection method used to observe it. Pulsars have been observed and studied across different wavelengths, and their appearance can vary depending on the observations made in various parts of the electromagnetic spectrum.