Visible light from the Sun is used by plants for growing. Other parts of the EM spectrum are used in many familiar devices like an X-ray machine that can take images of your bones, a tanning device that uses UV, night vision goggles that see in infrared, a microwave oven, and of course a radio receiver. ALL EM waves travel at the same speed in a vacuum, the speed of light. It’s about 300,000 kilometers per second. Light travels so fast that it would go around Earth seven and a half times in one second. Light from the Sun takes about 8 minutes to travel to Earth; a journey that’s an impressive 150,000,000 kilometers long. Some solar EM radiation, like UV and X-rays, are dangerous to life on Earth. Our atmosphere thankfully blocks most of the dangerous radiation from reaching the ground. Visible light and some UV get through but all the X-rays are blocked. Beyond the protective shield of our atmosphere, harmful radiations can pose a serious threat to astronauts in space.