The term "sun rays" is often used to refer to the electromagnetic radiation emitted by the Sun, primarily in the form of visible light. The speed of electromagnetic radiation in a vacuum, such as space, is approximately 299,792 kilometers per second (186,282 miles per second) which is commonly rounded to 300,000 kilometers per second for simplicity. This is commonly denoted as the speed of light (c). Therefore, sun rays, or light from the Sun, travel at the speed of light.