Here's why:

* Electromagnetic radiation: Gamma rays are a form of electromagnetic radiation, just like visible light, radio waves, and X-rays.

* Speed of light: All forms of electromagnetic radiation travel at the speed of light in a vacuum, which is approximately 299,792,458 meters per second (186,282 miles per second).

So, while gamma rays have much higher energy and shorter wavelengths than visible light, they still travel at the same incredible speed.