-- "The gravitational force between two masses acts along the line joining their centers of action. The force is proportional to the product of the two masses, and inversely proportional to the square of the distance between their centers of action."
Only portions of the electromagnetic spectrum is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light which have wavelengths from about 390 to 750 nm that is; ultraviolet light and visible light.
