How long does it take light from the Sun to reach Earth?
Sunlight takes about 8 minutes and 20 seconds to reach Earth. The Sun is about 150 million kilometers away, and light travels about 300,000 km every second.
The average distance between Earth and the Sun is about 149.6 million kilometers, a distance astronomers call one astronomical unit. Divide that by the speed of light and you get roughly 499 seconds. Because Earth's orbit is slightly oval, the time ranges from about 8 minutes 10 seconds in January to about 8 minutes 27 seconds in July.
This means we always see the Sun as it was a little over eight minutes ago. If the Sun suddenly vanished, we would keep seeing it and feeling its light for those eight minutes.
The light is much older than that
The energy in sunlight is made by nuclear fusion in the Sun's core. Before it escapes from the surface, that energy is absorbed and released again countless times as it works its way outward. Scientists estimate this journey takes tens of thousands of years or more, so the light warming you today began its trip long before human history was written down.
Did You Know?
Light from the nearest star after the Sun, Proxima Centauri, takes about 4.2 years to reach us. That is why astronomers measure such distances in light-years.